Nice to see a Pontiac motor. My family worked for Pontiac for years. Grandad even worked on the aluminium swiss cheese Super-Dutys in the early sixties.
I grew up working on Pontiacs with my Dad we both love them !! My Dad is currently in the hospital with congestive heart failure fighting to get better seeing this video brought tears to my eyes but I needed this Thank you Nick and everyone at Nicks Garage !!! Best of Luck from Tennessee
My Dad passed in 1993 he had a 67 GTO in 72 the timing cover developed a coolant leak which of course killed the engine we found a good replacement engine changed it out in the driveway and put headers on it oh the memories Thanks Nick !
The fact of Nick showing the entire world what he does and his extraordinary knowledge of old school american muscle engines mixed with the newer technology of his dyno is spectacularly interesting to me. Thank you Nick. I hope we get to watch you for many years to come. Love you guys.
Thanks for another great video!!! Back in the 80's my dad would get so mad at me. I was just a teen at the time and I would go through his spare carbs and steal all the secondary metering rods out of them to tune my GTO. I would steal the main rods and jets out of Rochester Dual Jets which were just the front half of a Quadrajet. They always had #74 or #75 main jets compared with anywhere from #67 to #72's on the regular Quadrajets. The main rods were also thinner on the Dual Jets. I ran a best of 12.98 with my old GTO back in the mid 80's so it was tuned pretty good for a high school kid!
Good points. I've always been a Q jet fan, and have witnessed the price increases lately. Grabbing tomorrow a trio of Q jets, headers and performance mufflers for $50 total, so there's still deals out there on Q jets. Edit: was supposed to, but the seller never bothered to show up. That was a 4 hr round trip wasted. and sellers wonder why interested parties ask, "is this still available" and other questions :) but Q jets are still cheap if you look--I bent a primary needle rebuilding the one on my 4-4-2, and rather than pay $29 + shipping for a new one, I went thru my shelf instead to find one from the carbs I got back when they were $5 in the dirt, $10 on the table at swap meets. Everyone wanted a Holley and just gave these things away.
Those beautiful exhaust manifolds are one reason why Ram Air Pontiacs do so well at the Pure Stock Muscle Car Drags. Most performance carmakers assumed that the first thing owners would do is throw the manifolds away and install headers. Pontiac made sure that you didn’t need to.
My electric bill is up 23% from last year. Fuel ⛽️ per gallon here in Central NY 4.34 for 87 , 4.45 for 89 , 4.99 for 93, 5.19 for 90 non ethanol. Pretty soon it will be essential trips only no joy rides any more sadly. I my fill my caprice ppv and drive it on weekends but not everyday. 455, sounds awesome at idle. It sounds so much smoother with the new cam and carb. That's interesting you showed me something I didn't know about Rochester carbs. Even know I had a book on them and rebuilt a few of them ty. 390 hp. isn't bad at all for a street driver. The tq. Is what moves the car anyway. Smiles 😃 per gallon ☺️ ! Thank you sir for all the information & thank the team for all the footage. Stay safe.
Nick, you been International for awhile and I love you are getting the Credit and Fame you deserve so much !!!!!!! You are one of a kind ,friendly , helpful to others ,and willing to share your knowledge .....As I said before you are one of the BEST here on TH-cam Nick . God Bless yall and take care . 🙂
Nick...we did experiment at the track years ago, and completely removed the secondary rods and hangers from a Pontiac engine. it ran the same time, with slightly higher mph, meaning it made more HP with the secondary rods/hangers completely removed ! on the 470 RA V tunnel port motor, I tried 3 carbs, an 800cfm Qjet, 750 CFM Holley list 3310, and an 1150 Holley Dominator, on the street, road tests. the Qjet, I had to remove both primary AND secondary rods/hangers, to get enough fuel in the motor at higher rpm, and the tunnel ram/tunnel port cylinder heads would suck the Qjet dry at high rpm, because the fuel bowl on a Qjet is so small. it ran out of fuel even with an electric pusher pump at tank, and mechanical pump on engine. yet- the Qjet had best low-midrange driveability, mileage. the 1150 Dominator was terrible at low-midrange, but had the most high end power above 5000 rpm. the 750 Holley did everything pretty good across the board, best idle, easiest to tune, so was the best compromise, that's what I ran. I still have that tweaked Qjet somewhere...it was Buick 800 cfm center, with Pontiac top/baseplate. but...just so you know, a Qjet will run, and run good, with no rods or hangers in it at all. and you can jet the front barrels like any other carb, up or down- providing the engine has that level appetite for fuel, which this one did. somewhere I have a can of Qjet rods, primary springs, hangers, and actually have the best "B" hanger which raises the secondary rods the highest out of the holes. the hangers are lettered, B is richest, C is leaner, so on... I also tried a vintage 1000 cfm Carter Competition Thermoquad on that RA V engine, it is basically a souped up Qjet on steroids, with dual floats, dual needle valves, dual feeds like a Holley, it solved that starvation problem. But the Holley 4 bbl still was best overall.
Installed a pair of custom thin secondary rods, .024, and later on had removed them completely. Test after test, hardly any change, and if any, a couple of HP.
I started with a 780 vacuum secondary 3310 as a replacement for the Qjet on my 67 GTO.....it wasn't a noticeable difference on the street but when the DP 750 came out I slipped that on. Much cleaner throttle response......but with my setup I wished that I had gone with the 850. Magazine tests also showed that above 34 degrees advance the oil temperature spiked. I ran 33 degrees with an Accel dual point with total advance at 2400. The GTO's ran too hot stock as the radiators weren't big enough to also have ac. They also reponded well to the 1.65 rocker arms.....
Good evening Nick and George. I've gotten into a habit of watching Nick's Garage in the evening on Monday's, so I can relax with a cup of coffee. You and George have come so far from the early days and have gotten better and better as the years, and the projects have gone by. All the while you have made us feel like we're part of a big and happy family. Merci pour tout ce que vous faites, en particulier la magie que vous faites sur ces muscle cars que nous connaissons et aimons tous au fil des ans. Personne ne le fait mieux que Nick's Garage !
I love Nick's work wish we had him here in Va. Love These 455 engines had one in a 1970 442 ram air made great torque and horse power. Im also a mopar Guy. Great job Nick.
Im a little late watching this Monday's show. I was glued to a documentary about Herb Mc Candless. Fantastic and I highly recommend it to anyone who likes drag racing and it's early years. Especially interesting for Mopar fans.
The valve covers should be chrome maybe they were to rusted to save. Those are ram air exhaust manifolds there almost as good as headers but he doesn't have ram air heads
Nick, I owned a ’78 Firebird “Poncho” but by then the horsepower and torque numbers were really watered down due to tightening emission requirements for newer vehicles. I became self-taught on Rochester carburetor overhaul when I took on clean up and install of a parts kit. My best accomplishment was fixing a binding secondary air valve shaft on a Rochester E4MC carburetor for my ’86 Oldsmobile Cutlass Supreme that I also owned at that time.
@MoparDan, that is cool Dan . It's is always rewarding figuring something out and making it work right and better . 78 Firebirds are nice too !!! Best Regards and take care .
The dyno room may spark the new viewer's curiosity, but it is your personality and work ethic that make people like me subscribe and continue to watch your channel. You have a very cool head & never seem to get upset about anything. Keep the videos rolling Nick.
It's the 455 Pontiac's final Dyno day It's certainly come a long way Previous horsepower attempts have not gone to plan So now installed is a competition cam Nick has uprated the set up with an 800 cfm carburettor because Nick is a horsepower proffessor There's no time for resting there's always more dyno testing on the Superflow dyno well worth investing in Which cam and carb will be the best only way to find out is a dyno test This pontiac looks superclean but it runs a little lean So Nick is fettling the fuel stream Todays weather was not great and horses it can take but this pontiac was solid make no mistake Nick's Garage every Monday set the time and date
Back in the 1970's and 80's HO Racing was big into Pontiacs. Once they were flogging their 455SD trans am at the track, accidentally left out the secondary metering rods and posted their best time ever. The big Pontiac's need more fuel to make max horsepower. A different carburetor on this engine might have gotten it over 400 HP? For reference, in 1969 the highest rated Pontiac engine was the 428 HO @ 390 HP, with a Qjet. A 455 with a larger bore and same stroke should be out performing the 428 with ease.
@@robertstout6980 the 428 was called the "Perfect Pontiac". However today aftermarket blocks have changed everything, but are expensive. Much appreciate the history lesson on H.O. Racing. I was given the grand tour in 1987. I was 19. They were building a 455 SD. They also had a turbo on another motor. '74 TA Red in the next bay, waiting for the 455 SD. I was a kid at the candy store!
Those Rochesters were excellent carbs. Not exactly gas efficient but they could provide fuel to make HP! They were pretty easy to work on too. Ahh... the good old days of wrenching.
You might could give a set of Doug,s Headers a try. A buddy and me put some on a 68 Firebird . These fell on, we put them in from the top. Best headers I,ve ever seen. Thanks for the show.
Cool engine ,it will be a great street engine with 500 ft lbs. Really like the look of those factory cast iron exhaust manifolds. Thanks as always Nick.
My first car was a 76 Grand Prix and that's when I started getting interested in Pontiac motors and GTOs. Dont own no Pontiac now but maybe in the future. My dream cars, a 73 GTO, a 76 Bonneville and 2 77 Can Ams.
Solid build with a nice sounding idle yet great vacuum. I've had a few quadrajets on the dyno over the years, and even with having 8 to 10 core carbs to rob parts from, I think I only found 3 different pairs of secondary rods. For anyone looking for a "performance" Rochester, I've been very happy with the "JET" brand remanufactured carbs. Keep in mind the D.A. once that engine is in the car and driving on an average spring day will be a bit richer, likely right in your target range of A/F.
Save the hangers for the secondary jets as they are identified by a letter , an A hanger would be the richest ,(holds the jets higher out of the carb) a Z hanger would be the leanest. There were many different letters used over the years.
@@basilcarroll9729 I knew there were different hangers but had no reference, information like what you stated is all but lost. I assume this is a tuning device in terms of mixture during transition of the air door, but once wide open the total jet area remains the same between hangers, is that correct? Thanks!
@@yarrdayarrdayarrda As I understand it, the hangers hold the jets from idle to full throttle higher .They are lettered B-V with .005 difference in height between letters. Yes for factory tunning purposes. A Quadrajet with .073 primary jets is not necessarily richer than a carb with .071 primary jets. It was the over all tuning to get the carb where they wanted. Also the tips of the secondary rods are tapered so if they are pulled up higher there is more jet area.
@@basilcarroll9729 Thanks for the information. I can't think of a single carb design that is more difficult to tune the primary side in terms of roll pins, screws, the choke rod, etc. Plus the hope the lid gasket doesn't rip.
Good Morning Nick & George, beaut looking & sounding poncho Nick & certainly runs real sweet. George a beaut video showing an overhead view of the carburetor working. Thanks guy's and have a beaut week.
Nick, you did a great job explaining the carbs way of delivering the fuel in full throttle. I had a 72-W-30 Hurst Olds Cutlass with a comp cam & headers, curbed the ignition. She was a handfull at full throttle. You had to make sure she was rolling straight, loved that car. Be careful & be safe.
Thank you Nick for making such a great show. Your dyno room videos are the best around. I grew up around Rochester Carbs. My Dad rebuilt hundreds of those Carbs. He knew them and liked them better than any other, because they gave you economy, and power in the secondaries. Watching them open on the video is what makes your show the best. All the classic muscle cars and regular cars too make the show real. Thank you for giving us something good to watch during these tough times we are in.
yeah with an F body and that torque it shall accelerate with less gearing and may even get a boost in mpg if its a lightweight+ 450 hp starts giving anything with tires a real bad problem anyway (so does low down torque hahahaha) who needs more HP on the street? torque baby , torque , all the way yeaH !
I wish I had this 455 in my 71 Grand Prix back in 1986, I might have been able to beat that 66 Shelby GT350 in a drag race. My 455 was rated at 325 SAE net HP with 455 ft lbs of torque. Thank you for the show Nick, you are the science professor of the automobile world.
I really enjoy this mechanic's session. I know of the metering rods. A 400 Chrysler with the Thermoquad,...has more metering rods,....6 metering rods! Thanks 😊!
Fantastic and great to see you again! To me it seem a Rochester carb is a more complicated design than say Holley. Those metering rods design is a great simple idea.
The Qjet is a more advanced design, not pretty though. For daily driving it's was superior to most Holley's. For performance, particularly with a manual Holley FTW.
I worked on the quadrajets many years ago. Great carb. But has a few issues. Polyurethane floats would get gas logged causing flooding. Replace that float every time. Also never over tighten the needle seat. Can strip threads. Can get repair oversize threads if that happens. Also wears where throttle shaft goes through. No brass bushings. Machine shop could repair that. Also the plugs under metering wells can leak. Some kits have a rubber like thinger that fits into cavity on lower throttle body and gets compressed when bowl is tightened sealing up leaking plugs.
I wish someone would make an updated version of a quadrajet. Edelbrock has there av whatever it's called but they are to small for a built engine. Holley just go ahead and kiss whatever resemblance of fuel mileage goodbye. Not to mention none of them have "the sound"😂😂 We just need a prettier modern version of a quadrajet that you don't need to disassemble to tune.
Gooooood Monday morning, Nick and crew!!!! That’s one torquey Pontiac: Olds and Buick were often the same, with truckloads of torque at the lower rpm levels. This’ll be a great all-around street engine. Nick, I believe it’s your open, honest and authentic approach to what you do and present to us viewers, that has made and is making you so popular AROUND THE WORLD!!! And George, your voice is the narrative signature for these great productions!!! Keep up the excellence, guys, and happy week to you all!!!
@@NicksGarage yessir!!! To all the fantastic people who watch the videos and live shows, you rock!!! And I’ve been telling people about Nick’s garage and hoping to add to the numbers!!
The 1976 Pontiac engine color is Oldsmobile metallic blue. 1977 was the first year for "corporate" blue. Great dyno session Nick. Thanks for sharing because we all learn together.
Hello Nick and Crew! A little late to the show today but I always make the time to get more MoPar (and Pontiac) knowledge from the KIng of MoPar Muscle!
Nick, those H.O. Pontiac exhaust manifolds work as well as my three tube headers. Plus you get more clearance under the car. I'm switching to them on my 400.
Nick your world famous! I really enjoyed the commentary. This runup did more for me than my first cup of coffee. Lol. I'd like to use the run for a ringtone! I'm the 455HO Poncho guy.
Hmm...as I recall (sort of), there's a few more games the owner could play, with the secondaries. I think the Buick and Cad 850's came with a secondary hanger that had enough meat to drill the holes higher to get to the "thin" part of the rod faster. There were also higher ratio secondary hanger cams (the plastic piece that lifts the hanger), but I think those were aftermarket units. I don't recall finding any different ones in junkyards.
Thanks again Mate" Compression on the engines after around 1973 especially the big blocks were terrible but they still had good torque and were easy to get breathing better but we didn,t have parts like we do now............ i remember a 1974 396021F 455 olds 4bbl engine i bought used was rated at 220hp and used more fuel than a WW2 tank i had the engine in a Holden Monaro.. Pontiac made some great engines and i was told years ago the Pontiac 400 Ram air engine had the biggest rochesters on them CFM wise. How true i dont know. I still have a set of 500ci caddy metering rods given to me by a buick spare parts shop in Sydney Australia in 1979. Seems like yesterday. Thanks Nick great engine mate.
Hi nick & company, in this crazy world we're living in, I love watching your videos, such a great for me! Love Melissa, Nick, George and all the rest of the crew. You together do a wonderful job! Bring some sanity to my crazy world! Looking forward to the next one!!!
This is why I like custom ground cams from people that understand what it takes to get the best out of each brand. At the end of the day, all engines are the same.....pistons go up and down, crank goes round and round ( quoted from the great Bob Glidden )
Nick, your right putting on headers can be tricky. Sometimes I think 🤔 I'd rather pull the motor & put them on , then drop the motor back. Good point 👉, Nick!
In my 60 years of wrenching on cars and carburetors I'm glad I can relive the fun by watching your videos. Unfortunately for me I did not have the luxury of a dyno. I had to do everything with the engines in the cars. As you say on occasion, "no matter." It's the end result that does matter. I am now going to "fire up" another one of your excellent videos. And yes, I am a subscriber.
Thanks for the follow-up testing Nick! I appreciate you giving us a baseline so to speak by using the factory style divided-runner cast iron exhaust manifolds and Q-Jet on this undersquare engine.
Hi Nick, I used to have a 77 Trans Am with a 1970 455 .030 over XF block, 96 Heads. The headers that worked well I had purchased from Ken Crocie of HO Racing (no longer available)... Tri-Y headers that fit well, hugged the engine without interfering with the steering or starter. I think the Tri-Y's from Hedman Hedders might also work out for your client.
I've been running a lunati solid lifter cam in my 455 for over 20 years. I love it. Most people think I'm nuts running a solid in a pontiac. But with the lifter restrictors, I've never had a problem with starvation from too much oil on the top end
I always learn something when I watch your channel. My last experience with a carb swap was on Camaro 350 from stock Rochester q uad jet to a Holly 650 .. direct bolt on mod. Without much fiddling around on the Holly's fuel mix it really seemed to provide so much more power.
Giasou Nikola, Can't keep a good Poncho down, the old story " There are no substitute for Cube ". You got to be happy with the numbers & getting your dyno back. Your number 1 Fan in Australia Louis Kats from Melbourne Australia ☺ 👍 ❤
its a sweet deal to see you tame da poncho nick. dad was pro pontiac. ya gotta take a little liking to those 455ci pontys. after all shes one of chryslers best competitors. thanks you guys,,
I love these comparison videos. They show how these engines respond to changes. The dyno does not lie. Great work as always George. Can’t wait to see what’s next on the dyno. Have a great week Nick and crew.
I recurve a HEI distributor to duplicate the highest output 350 corvette engine. I shortened the advance curve and all adjustments to the vacuum advance. Placed in a modified 350 chevy engine to the surprise of the owner the power increase gave him wheel hoping on hard launches. Distributor modifications are always almost never done. But done properly you can gain power, engine response quickens and normal a plus on mpg .
Nick I think you’re a machine shop angle thank you for teaching me how to put cam berries in your show is my favorite entertainment 👍🎃👍I wish you all the best 🏆🏆🏆🛠️
Loved the video. Reminds of my youth when I had a '71 GTO with a 400 manual trans, a Chevy 12 bolt with 4.10 gears. I built that motor a bit more radical than this one and wish I could have put it on a dyno to see what the actual power output was. I had a Crane Fireball Cam (28428) in it. Lots of power for a heavy car. I still have the cam specification sheet I wish I still had the car.
Great video, Nick. I like to see dyno results in street trim, the manifolds that are installed on the car. With an exhaust system connected, we see diminishing differences between headers, and a free breathing stock "HO" exhaust manifold. These Pontiac engines with large valve heads (389 400, 421, and 455) produce very flat torque curves, and are extremely responsive on the street. By the time (some) other high performance engines develop horsepower, the Pontiac has already developed gobs of torque and horsepower, very quickly. it's not always all about max horsepower that an engine builds, it's how quickly it can build horsepower. Throttle response makes a car more drivable, a more exciting driving experience.
Nick, you are so right about them making you pay in other ways. Now we have to pay to import oil from halfway around the world, when we could get it in our backyard.
I tried to order a Lunati cam during the pandemic. Ended up going with something else because they were unfortunately very backlogged on orders. Can't wait to see the difference...watching now.
Well that was a decent HP gain from basically a cam change. The 800 rochester I bet really didnt do anything for power over the 750 as long as the a/f ratios were the same. That motor doesnt need anymore than 750 cfm. About a 10 degree increase on intake and exhaust duration and a little more lift. You wouldnt want to go any bigger on the cam with the compression ratio at where it is. Basically you have a stock pontiac 455 with mild compression,stock flowing heads,stock intake and exhaust manifolds and a decent cam and made 395hp and over 500 trq.. Id say thats pretty good. Theres always more to be had with that motor like porting the heads but thats more time and money. You should be happy once its in the car,,,should really pin you in the seat!
Hey Nick ,George, and Krew , Good Morning to all . Love seeing the ol Tin Indian making noise and I fully agree with you Nick about the headers and putting it over 400 hp . Sure Good to start my day at your garage. Enjoy the dyno days too . I remember the earlier Pontiacs engines were painted a green color which had a sparkle to it and them using Wolf Head Oil back in those days . Nick ,do you remember what the green color was called for the earlier Pontiac engines ?
@@nickpanaritis4122 Hey Nick , Thank-you for the reply . For some reason I was thinking it was a greener tint to it . But I knew you would have the correct answer . I like the earlier color on the Tin Indians, but I believe in doing the way it came from the factory and to specs . Thats one thing I love about how you do things ,there is no guessing, by the factory specs and attention to detail all the time . Do it right the 1st time . It was fun to see the 455 get its final test done and pretty good numbers too ...I'm now wanting to see what the early 50s Hemi you have in the shop will do when you get it done . I don't know who you have doing the block working and cleaning, but they sure have the old hemi block looking great . I truly enjoy all the dynos you do and the knowledge ,detail ,and the years of experience you show when doing them . Like I said before, you are a Master Master Mechanic hands down . Sorry for getting long winded Nick . Always a pleasure to talk with you and I very much appreciate your time Nick to respond to me . I know you are a Super Busy Man . God Bless you and your Family, and be safe . Best Regards.
The Pontiac 455 made decent power with the stock unported 1971 #96 400 Heads. #96 heads flow just 195 cfm @ 28 inches water Depression. So it was making 2 hp per 1.0 cfm intake flow with less than ideal 100% Volumetric efficiency of the 455 engine. Not many other pushrod engines can do the same engine Parameters used.
@BrRe, using another Pontiac motor for comparison. In your opinion, is there advantages with the 428 over the 455? Respectfully referring to 1969 428 H.O. and the 1971 455 H.O. ?
@@kevinmanning4880 If you compare the 428 HO and 1971 455 HO engines 100 % Pure Stock built exact as Pontiac built them with 100% Original NOS GM parts the 428 HO will make more peak Hp at 390 Hp with 110 motor octane Race gasoline, high compression and high peak cranking and dynamic and effective compression ratio. Zero detonation Operation Full ignition advance used requirements met with modern Race fuel 110 octane. The 1971 HO 455 is actually making a solid 350 Hp at the Flywheel on 91 octane gasoline what was Regular Fuel in 1971 year. Reports they run on 87 octane modern gasoline Ignition timing pulled back to 32 degrees BTDC No Vacuum advance used any. The 1971 455 HO makes more torque rated at 480 ft/lbs. Its actually 510- 520 ft/lbs at the Flywheel. The 1971 455 HO in a 1971 Pontiac Trans Am will Win the Street Drag Race. Cylinder heads on the 1971 455HO Roundport exhaust are Superior over the 428 H0 D-port #16 & #62. The 455 H0 engine intake ports flow more air a stronger entire flow curve .050" - .550" lift. The Round port exhaust doesn't show all what it actually does on a flow bench but it moves more air Yes than most D-ports. Been proven measuring exhaust port flow on a flowbench a waste of time by many pros, Its not stimulating the exhaust energy present moving above the speed of sound, really best measured in Joules of Energy. Superior Valve flow curtain on the 455 HO. No doubt the 428 HO is still a Powerful street engine. 428 HO has a slightly better R/S rod to stroke ratio than a 455. Makes less torque but was a Favorite of 1st Generation Firebird owners because they are traction limited unless they use Super Stock Drag Racing traction tricks or a Modern 4-link rear end layout. 2nd Generation Firebird Trans Am has the Superior Suspension best of any Pontiac ever built for Handling plus Street Drag Racing. Both Fantastic engines and Legendary 428 HO and 455 HO. Choose what you Love. Everything changes when You Port Pontiac Iron or Aluminum Cylinder Heads. CNC machined doesn't give optimal results like many think. Often fails on the streets and racetrack CNC Heads. There is No Substitute for Hand Cylinder Heads and Intake Porting. Very Difficult Skills to Learn and Apply. I do it learned from the Worlds Best Cylinder head Porters. It's a Secret Club.
@@kevinmanning4880 Nothing helps promote easy to obtain torque and Hp Gains in a Pontiac V8 using 12.0:1 & 13.0:1 static compression ratios they become explosive Powerful. At 700 Hp + with Factory Pontiac Iron RAIV 614 Roundport heads. Been there done it Raced with. Problem is 110 Motor octane gasoline is so expensive now. Back in the day I was paying $2.99 per gallon for 110 octane a great deal now with gasoline 87 octane at $5 per gallon average. Canada where Nick is at much higher over $8 per gallon. They make stellar power still on 91 -93 octane if planned carefully built for. Cylinder head Porting and intake Porting by hand required. 87 Octane be best to build for cruising duties long distances driven. Calculated on paper be down 40 Hp approximately over 91-93 octane. Seems terrible to lose torque and Hp over 91-93 but advantages clearly there every time at the gas pump to fill up 16-20 gallons the Fuel Cell or Fuel tank. 12.0:1 - 13.0:1 Pontiac V8 worth +100 - + 200 Hp more depending upon design parameters of the entire engine. No cheeting octane required for them. Need 110-112 motor octane Race Fuel. Or E85 or Methanol Alcohol Fuel.
@@brracing7861 much appreciate your valuable information. I've been a Pontiac enthusiast since 1985 at 17. Married, house kids, then divorce and destitute. Managed to hang on to my '70 GTO all these years. After blowing up a 428, I have another one, low mileage rebuild, looking for advice on what heads to swap to. I really like what you said about hand porting over "CnC porting". Didn't the 428 HO come with #48 heads? Would round port heads on a 428 make some advantages in powerband characteristics over the 455 or is it advantageous for the 455 over the 428? Just curious since the 428 is a square motor.
Nice to see a Pontiac motor. My family worked for Pontiac for years. Grandad even worked on the aluminium swiss cheese Super-Dutys in the early sixties.
I grew up working on Pontiacs with my Dad we both love them !! My Dad is currently in the hospital with congestive heart failure fighting to get better seeing this video brought tears to my eyes but I needed this Thank you Nick and everyone at Nicks Garage !!! Best of Luck from Tennessee
Thank you Mark. All the best to you and your dad.
Sending the best to your Dad, You, and your whole family!
My Dad passed in 1993 he had a 67 GTO in 72 the timing cover developed a coolant leak which of course killed the engine we found a good replacement engine changed it out in the driveway and put headers on it oh the memories Thanks Nick !
@@DrGo-bw2jy that means a lot thank you 🙏
@@kwhite145 we definitely gotta cherish the ones we love and the memories!!
The fact of Nick showing the entire world what he does and his extraordinary knowledge of old school american muscle engines mixed with the newer technology of his dyno is spectacularly interesting to me. Thank you Nick. I hope we get to watch you for many years to come. Love you guys.
Us old school Q-jet users used to go rob the rods from 472 or 500 caddys for the really thin tips..
I could listen to this guy all day.
Thanks for another great video!!! Back in the 80's my dad would get so mad at me. I was just a teen at the time and I would go through his spare carbs and steal all the secondary metering rods out of them to tune my GTO. I would steal the main rods and jets out of Rochester Dual Jets which were just the front half of a Quadrajet. They always had #74 or #75 main jets compared with anywhere from #67 to #72's on the regular Quadrajets. The main rods were also thinner on the Dual Jets. I ran a best of 12.98 with my old GTO back in the mid 80's so it was tuned pretty good for a high school kid!
Good points. I've always been a Q jet fan, and have witnessed the price increases lately. Grabbing tomorrow a trio of Q jets, headers and performance mufflers for $50 total, so there's still deals out there on Q jets.
Edit: was supposed to, but the seller never bothered to show up. That was a 4 hr round trip wasted. and sellers wonder why interested parties ask, "is this still available" and other questions :) but Q jets are still cheap if you look--I bent a primary needle rebuilding the one on my 4-4-2, and rather than pay $29 + shipping for a new one, I went thru my shelf instead to find one from the carbs I got back when they were $5 in the dirt, $10 on the table at swap meets. Everyone wanted a Holley and just gave these things away.
Ha! I got so tired of my Dad raiding the carbs i switched to Holley's.
Those beautiful exhaust manifolds are one reason why Ram Air Pontiacs do so well at the Pure Stock Muscle Car Drags. Most performance carmakers assumed that the first thing owners would do is throw the manifolds away and install headers. Pontiac made sure that you didn’t need to.
My electric bill is up 23% from last year.
Fuel ⛽️ per gallon here in Central NY
4.34 for 87 , 4.45 for 89 , 4.99 for 93, 5.19 for 90 non ethanol.
Pretty soon it will be essential trips only no joy rides any more sadly.
I my fill my caprice ppv and drive it on weekends but not everyday.
455, sounds awesome at idle.
It sounds so much smoother with the new cam and carb.
That's interesting you showed me something I didn't know about Rochester carbs. Even know I had a book on them and rebuilt a few of them ty.
390 hp. isn't bad at all for a street driver. The tq. Is what moves the car anyway.
Smiles 😃 per gallon ☺️ !
Thank you sir for all the information & thank the team for all the footage.
Stay safe.
Dr. Nick thanks for the 2nd dyno show on the Pontiac 455, and that overhead shot on the Rochester at full throttle,well done, cheers.
Nick, you been International for awhile and I love you are getting the Credit and Fame you deserve so much !!!!!!! You are one of a kind ,friendly , helpful to others ,and willing to share your knowledge .....As I said before you are one of the BEST here on TH-cam Nick . God Bless yall and take care . 🙂
Thanks Sarge!
Professional grade videos and advice. If Netflix hasn't already approached you, you should approach them.
Nick...we did experiment at the track years ago, and completely removed the secondary rods and hangers from a Pontiac engine. it ran the same time, with slightly higher mph, meaning it made more HP with the secondary rods/hangers completely removed ! on the 470 RA V tunnel port motor, I tried 3 carbs, an 800cfm Qjet, 750 CFM Holley list 3310, and an 1150 Holley Dominator, on the street, road tests. the Qjet, I had to remove both primary AND secondary rods/hangers, to get enough fuel in the motor at higher rpm, and the tunnel ram/tunnel port cylinder heads would suck the Qjet dry at high rpm, because the fuel bowl on a Qjet is so small. it ran out of fuel even with an electric pusher pump at tank, and mechanical pump on engine. yet- the Qjet had best low-midrange driveability, mileage. the 1150 Dominator was terrible at low-midrange, but had the most high end power above 5000 rpm. the 750 Holley did everything pretty good across the board, best idle, easiest to tune, so was the best compromise, that's what I ran. I still have that tweaked Qjet somewhere...it was Buick 800 cfm center, with Pontiac top/baseplate.
but...just so you know, a Qjet will run, and run good, with no rods or hangers in it at all. and you can jet the front barrels like any other carb, up or down- providing the engine has that level appetite for fuel, which this one did. somewhere I have a can of Qjet rods, primary springs, hangers, and actually have the best "B" hanger which raises the secondary rods the highest out of the holes. the hangers are lettered, B is richest, C is leaner, so on...
I also tried a vintage 1000 cfm Carter Competition Thermoquad on that RA V engine, it is basically a souped up Qjet on steroids, with dual floats, dual needle valves, dual feeds like a Holley, it solved that starvation problem. But the Holley 4 bbl still was best overall.
A w31 olds had no power valve and metering rods for the primaries it looked like a small freeze plug here the power valve should of been poor mileage
The older 3310 Hollies were one of the best overall carburetors you can buy back years ago I had one that worked on any car I put it on
Installed a pair of custom thin secondary rods, .024, and later on had removed them completely. Test after test, hardly any change, and if any, a couple of HP.
I started with a 780 vacuum secondary 3310 as a replacement for the Qjet on my 67 GTO.....it wasn't a noticeable difference on the street but when the DP 750 came out I slipped that on. Much cleaner throttle response......but with my setup I wished that I had gone with the 850. Magazine tests also showed that above 34 degrees advance the oil temperature spiked. I ran 33 degrees with an Accel dual point with total advance at 2400. The GTO's ran too hot stock as the radiators weren't big enough to also have ac. They also reponded well to the 1.65 rocker arms.....
Good evening Nick and George. I've gotten into a habit of watching Nick's Garage in the evening on Monday's, so I can relax with a cup of coffee. You and George have come so far from the early days and have gotten better and better as the years, and the projects have gone by. All the while you have made us feel like we're part of a big and happy family. Merci pour tout ce que vous faites, en particulier la magie que vous faites sur ces muscle cars que nous connaissons et aimons tous au fil des ans. Personne ne le fait mieux que Nick's Garage !
Love the torque numbers on this Poncho! Almost 400 hp should make for some fun on the street. Thank you Nick for another great Dyno presentation!
I love Nick's work wish we had him here in Va. Love These 455 engines had one in a 1970 442 ram air made great torque and horse power. Im also a mopar Guy. Great job Nick.
Im a little late watching this Monday's show. I was glued to a documentary about Herb Mc Candless. Fantastic and I highly recommend it to anyone who likes drag racing and it's early years. Especially interesting for Mopar fans.
I don't know if anybody's ever told you this but you got the best camera guy on TH-cam
Wow! Thank you.
That blue is gorgeous, and those headers are a cool shape - thanks for showing us this great motor
The valve covers should be chrome maybe they were to rusted to save. Those are ram air exhaust manifolds there almost as good as headers but he doesn't have ram air heads
Pontiac dropped the chrome valve covers in 76.
Nick, I owned a ’78 Firebird “Poncho” but by then the horsepower and torque numbers were really watered down due to tightening emission requirements for newer vehicles. I became self-taught on Rochester carburetor overhaul when I took on clean up and install of a parts kit. My best accomplishment was fixing a binding secondary air valve shaft on a Rochester E4MC carburetor for my ’86 Oldsmobile Cutlass Supreme that I also owned at that time.
@MoparDan, that is cool Dan . It's is always rewarding figuring something out and making it work right and better . 78 Firebirds are nice too !!! Best Regards and take care .
The dyno room may spark the new viewer's curiosity, but it is your personality and work ethic that make people like me subscribe and continue to watch your channel. You have a very cool head & never seem to get upset about anything. Keep the videos rolling Nick.
It's the 455 Pontiac's final Dyno day It's certainly come a long way Previous horsepower attempts have not gone to plan So now installed is a competition cam Nick has uprated the set up with an 800 cfm carburettor because Nick is a horsepower proffessor There's no time for resting there's always more dyno testing on the Superflow dyno well worth investing in Which cam and carb will be the best only way to find out is a dyno test This pontiac looks superclean but it runs a little lean So Nick is fettling the fuel stream Todays weather was not great and horses it can take but this pontiac was solid make no mistake Nick's Garage every Monday set the time and date
You are WAY over selling and average engine rebuilder.
Back in the 1970's and 80's HO Racing was big into Pontiacs. Once they were flogging their 455SD trans am at the track, accidentally left out the secondary metering rods and posted their best time ever. The big Pontiac's need more fuel to make max horsepower. A different carburetor on this engine might have gotten it over 400 HP? For reference, in 1969 the highest rated Pontiac engine was the 428 HO @ 390 HP, with a Qjet. A 455 with a larger bore and same stroke should be out performing the 428 with ease.
@@robertstout6980 the 428 was called the "Perfect Pontiac". However today aftermarket blocks have changed everything, but are expensive. Much appreciate the history lesson on H.O. Racing. I was given the grand tour in 1987. I was 19. They were building a 455 SD. They also had a turbo on another motor. '74 TA Red in the next bay, waiting for the 455 SD. I was a kid at the candy store!
Do you fetch Nick's coffee?😄
@@MH-WM from London? No that would be sillier than your question
Awesome show for a Monday morning , had a Q-jet on a 283 on a 4 speed "64 Elcamino , felt like a volcanic explosion when I opened all 4 barrels up !
That sound, you don't forget that sound. Especially if you flipped the air cleaner lid over so you got more air in and more sound out.
Those Rochesters were excellent carbs. Not exactly gas efficient but they could provide fuel to make HP! They were pretty easy to work on too. Ahh... the good old days of wrenching.
You might could give a set of Doug,s Headers a try. A buddy and me put some on a 68 Firebird . These fell on, we put them in from the top. Best headers I,ve ever seen. Thanks for the show.
Cool engine ,it will be a great street engine with 500 ft lbs. Really like the look of those factory cast iron exhaust manifolds. Thanks as always Nick.
I though they were pretty slick as well
My first car was a 76 Grand Prix and that's when I started getting interested in Pontiac motors and GTOs. Dont own no Pontiac now but maybe in the future. My dream cars, a 73 GTO, a 76 Bonneville and 2 77 Can Ams.
I love Pontiac. The 1970's cars are the best.
Nice video. Back in ‘76 I had a Super Duty 455 built for me by H. O. Racing Specialties in Lawndale Calif. What a monster that motor was.
Solid build with a nice sounding idle yet great vacuum. I've had a few quadrajets on the dyno over the years, and even with having 8 to 10 core carbs to rob parts from, I think I only found 3 different pairs of secondary rods. For anyone looking for a "performance" Rochester, I've been very happy with the "JET" brand remanufactured carbs.
Keep in mind the D.A. once that engine is in the car and driving on an average spring day will be a bit richer, likely right in your target range of A/F.
Save the hangers for the secondary jets as they are identified by a letter , an A hanger would be the richest ,(holds the jets higher out of the carb) a Z hanger would be the leanest. There were many different letters used over the years.
@@basilcarroll9729 I knew there were different hangers but had no reference, information like what you stated is all but lost.
I assume this is a tuning device in terms of mixture during transition of the air door, but once wide open the total jet area remains the same between hangers, is that correct?
Thanks!
@@yarrdayarrdayarrda As I understand it, the hangers hold the jets from idle to full throttle higher .They are lettered B-V with .005 difference in height between letters. Yes for factory tunning purposes. A Quadrajet with .073 primary jets is not necessarily richer than a carb with .071 primary jets. It was the over all tuning to get the carb where they wanted. Also the tips of the secondary rods are tapered so if they are pulled up higher there is more jet area.
@@basilcarroll9729 Thanks for the information. I can't think of a single carb design that is more difficult to tune the primary side in terms of roll pins, screws, the choke rod, etc. Plus the hope the lid gasket doesn't rip.
@@yarrdayarrdayarrda Yes and careful not to bend the primary metering rods when reinserting them lol
i love the dyno videos especialy when theres a comparison cam or carburators or headers vs manifolds etc
Good Morning Nick & George, beaut looking & sounding poncho Nick & certainly runs real sweet. George a beaut video showing an overhead view of the carburetor working. Thanks guy's and have a beaut week.
Nick, you did a great job explaining the carbs way of delivering the fuel in full throttle. I had a 72-W-30
Hurst Olds Cutlass with a comp cam & headers, curbed the ignition. She was a handfull at full
throttle. You had to make sure she was rolling straight, loved that car. Be careful & be safe.
Thank you Nick for making such a great show. Your dyno room videos are the best around. I grew up around Rochester Carbs. My Dad rebuilt hundreds of those Carbs. He knew them and liked them better than any other, because they gave you economy, and power in the secondaries. Watching them open on the video is what makes your show the best. All the classic muscle cars and regular cars too make the show real. Thank you for giving us something good to watch during these tough times we are in.
Gota love just a "mild engine for the street" with over 500 lb ft of torque! Will be a blast to drive in an F-body
yeah with an F body and that torque it shall accelerate with less gearing and may even get a boost in mpg if its a lightweight+ 450 hp starts giving anything with tires a real bad problem anyway (so does low down torque hahahaha) who needs more HP on the street? torque baby , torque , all the way yeaH !
I wish I had this 455 in my 71 Grand Prix back in 1986, I might have been able to beat that 66 Shelby GT350 in a drag race. My 455 was rated at 325 SAE net HP with 455 ft lbs of torque. Thank you for the show Nick, you are the science professor of the automobile world.
Got my coffee in my Nick's Garage coffee mug and I'm going to enjoy the show!
Rock on!
I really enjoy this mechanic's session. I know of the metering rods. A 400 Chrysler with the Thermoquad,...has more metering rods,....6 metering rods!
Thanks 😊!
Fantastic and great to see you again! To me it seem a Rochester carb is a more complicated design than say Holley. Those metering rods design is a great simple idea.
The Qjet is a more advanced design, not pretty though. For daily driving it's was superior to most Holley's. For performance, particularly with a manual Holley FTW.
I worked on the quadrajets many years ago. Great carb. But has a few issues. Polyurethane floats would get gas logged causing flooding. Replace that float every time. Also never over tighten the needle seat. Can strip threads. Can get repair oversize threads if that happens. Also wears where throttle shaft goes through. No brass bushings. Machine shop could repair that. Also the plugs under metering wells can leak. Some kits have a rubber like thinger that fits into cavity on lower throttle body and gets compressed when bowl is tightened sealing up leaking plugs.
I wish someone would make an updated version of a quadrajet. Edelbrock has there av whatever it's called but they are to small for a built engine. Holley just go ahead and kiss whatever resemblance of fuel mileage goodbye. Not to mention none of them have "the sound"😂😂 We just need a prettier modern version of a quadrajet that you don't need to disassemble to tune.
Gooooood Monday morning, Nick and crew!!!! That’s one torquey Pontiac: Olds and Buick were often the same, with truckloads of torque at the lower rpm levels. This’ll be a great all-around street engine. Nick, I believe it’s your open, honest and authentic approach to what you do and present to us viewers, that has made and is making you so popular AROUND THE WORLD!!! And George, your voice is the narrative signature for these great productions!!! Keep up the excellence, guys, and happy week to you all!!!
Thank you Joel. And don’t forget our incredible, passionate viewers. Like you, they make the channel.
@@NicksGarage yessir!!! To all the fantastic people who watch the videos and live shows, you rock!!! And I’ve been telling people about Nick’s garage and hoping to add to the numbers!!
Good comparison nick everybody likes to no the difference in cams what works in different engines thanksnick
I like it....metering rods are new to me, but then, I'm working with old holy 94's from the 50's.
Yes I've rebuilt it and fixed all the known issues. Just a lemon carb....
The 1976 Pontiac engine color is Oldsmobile metallic blue. 1977 was the first year for "corporate" blue. Great dyno session Nick. Thanks for sharing because we all learn together.
Hello Nick and Crew! A little late to the show today but I always make the time to get more MoPar (and Pontiac) knowledge from the KIng of MoPar Muscle!
I Love Mopars more than any thing but i Love Nicks Dyno room with any engine even more . What a great Monday
Great to see a Quadrajet on the Pontiac they are a great carb ! They got a bad rap over years I just think people didn’t understand them is all
I would straighten the hanger out besides tapering the metering rods. Love those Rochester Carbs
That's right Nick.. the man will have his pound of flesh no matter what.. Nice show.. love watching this dyno room..
No better way to start a Monday off than watching Nick! Thanks for posting your video(s) too!
Glad you like them! Thanks for watching!
Nick, those H.O. Pontiac exhaust manifolds work as well as my three tube headers. Plus you get more clearance under the car. I'm switching to them on my 400.
You guys could turn the lights off to see if the plug wires are grounding on anything .
That 455 is very impressive considering its running iron exhaust manifolds, stock heads and especially the stock intake!
The stock Pontiac intake was one of the best factory pieces ever...from ANY marque
Pontiac was IMO the only GM marque that really threatened Mopar on a regular basis...TORQUE
Nick your world famous! I really enjoyed the commentary. This runup did more for me than my first cup of coffee. Lol. I'd like to use the run for a ringtone! I'm the 455HO Poncho guy.
Glad you enjoyed! Thanks Rick.
Hmm...as I recall (sort of), there's a few more games the owner could play, with the secondaries. I think the Buick and Cad 850's came with a secondary hanger that had enough meat to drill the holes higher to get to the "thin" part of the rod faster. There were also higher ratio secondary hanger cams (the plastic piece that lifts the hanger), but I think those were aftermarket units. I don't recall finding any different ones in junkyards.
Thanks again Mate" Compression on the engines after around 1973 especially the big blocks were terrible but they still had good torque and were easy to get breathing better but we didn,t have parts like we do now............ i remember a 1974 396021F 455 olds 4bbl engine i bought used was rated at 220hp and used more fuel than a WW2 tank i had the engine in a Holden Monaro.. Pontiac made some great engines and i was told years ago the Pontiac 400 Ram air engine had the biggest rochesters on them CFM wise. How true i dont know. I still have a set of 500ci caddy metering rods given to me by a buick spare parts shop in Sydney Australia in 1979. Seems like yesterday. Thanks Nick great engine mate.
good morning nick just got to love the sound of a big block great video have a great week
No the weather is not good for making HP but it is what it is.....Thanks Nick and l really like Georges lighting set up🔴🔵🟣🟢⚪👀....Thanks George 👍
Hi nick & company, in this crazy world we're living in, I love watching your videos, such a great for me! Love Melissa, Nick, George and all the rest of the crew. You together do a wonderful job! Bring some sanity to my crazy world! Looking forward to the next one!!!
Thanks so much! We appreciate you.
This is why I like custom ground cams from people that understand what it takes to get the best out of each brand. At the end of the day, all engines are the same.....pistons go up and down, crank goes round and round ( quoted from the great Bob Glidden )
Well said!
@Car Guy daddyo .. Yes, indeed.
Well, sort of.
RA exhaust manifolds are the right choice for many!
Nick, your right putting on headers can be tricky. Sometimes I think 🤔 I'd rather pull the motor & put them on , then drop the motor back. Good point 👉, Nick!
In my 60 years of wrenching on cars and carburetors I'm glad I can relive the fun by watching your videos. Unfortunately for me I did not have the luxury of a dyno. I had to do everything with the engines in the cars. As you say on occasion, "no matter." It's the end result that does matter. I am now going to "fire up" another one of your excellent videos. And yes, I am a subscriber.
Love that 455! Thank you Nick and crew!
Thanks for watching. Tell a friend?
IMO, dyno days are the best. Thanks for taking us along for the ride Nick.
thanks nick for your pontiac work for the pontiac community!
Thanks for the follow-up testing Nick! I appreciate you giving us a baseline so to speak by using the factory style divided-runner cast iron exhaust manifolds and Q-Jet on this undersquare engine.
Those are probably one of the best "exhaust manifolds" I've seen. As close to a header in cast iron as you're gonna get.
Pontiac was pretty neat about that, and being thick cast iron, they can be ported like a cylinder head as well for better flow.
Long branches flow better
Lot faster changing metering rods on a Rochester than jets on a Holley . Less messy too.
A Novice trying ot work on hsi own Pontiac Engine can learn so much just by watching Nick's Videos and watching him tune it.
Hi Nick, I used to have a 77 Trans Am with a 1970 455 .030 over XF block, 96 Heads. The headers that worked well I had purchased from Ken Crocie of HO Racing (no longer available)... Tri-Y headers that fit well, hugged the engine without interfering with the steering or starter. I think the Tri-Y's from Hedman Hedders might also work out for your client.
I have a set of those
I've been running a lunati solid lifter cam in my 455 for over 20 years. I love it. Most people think I'm nuts running a solid in a pontiac. But with the lifter restrictors, I've never had a problem with starvation from too much oil on the top end
I always learn something when I watch your channel. My last experience with a carb swap was on Camaro 350 from stock Rochester q uad jet to a Holly 650 .. direct bolt on mod. Without much fiddling around on the Holly's fuel mix it really seemed to provide so much more power.
Giasou Nikola,
Can't keep a good Poncho down, the old story
" There are no substitute for Cube ".
You got to be happy with the numbers & getting your dyno back.
Your number 1 Fan in Australia
Louis Kats from Melbourne Australia ☺ 👍 ❤
Great to see this engine running like a HERO. Cheers guys 👍 💯
its a sweet deal to see you tame da poncho nick. dad was pro pontiac. ya gotta take a little liking to those 455ci pontys. after all shes one of chryslers best competitors. thanks you guys,,
My 69 Oldsmobile Toronado had 455.I fueled with sunoco 260 which was "white" gas.Wish I still had.
Awesome motor and I think it's cool to watch the carburetor work!
We agree!
400 Ponies and 500 ft lbs of torque...sounds like alot of fun and massive tire smoke ahead....
I think the biggest gain from the changes is an extra 300 rpm of rev range to the peak, a bit more fun than a motor that runs out of breath at 4,600
I love these comparison videos. They show how these engines respond to changes. The dyno does not lie. Great work as always George. Can’t wait to see what’s next on the dyno. Have a great week Nick and crew.
Really cool. I have the same 455 setup
SOME GREAT NUMBERS with that torque you could pull a house down the road , that will be one fun pontiac on the road
Nick just soooo enjoy watching and learning from y’all , goooooo mopar !!!! Working on a 360 LA block old school for my 92 one ton
I recurve a HEI distributor to duplicate the highest output 350 corvette engine. I shortened the advance curve and all adjustments to the vacuum advance. Placed in a modified 350 chevy engine to the surprise of the owner the power increase gave him wheel hoping on hard launches. Distributor modifications are always almost never done. But done properly you can gain power, engine response quickens and normal a plus on mpg .
Nick I think you’re a machine shop angle thank you for teaching me how to put cam berries in your show is my favorite entertainment 👍🎃👍I wish you all the best 🏆🏆🏆🛠️
Sweet! Been busy but catching up guys! See you in May!
Be careful with those chainsaws. 🌲
Loved the video. Reminds of my youth when I had a '71 GTO with a 400 manual trans, a Chevy 12 bolt with 4.10 gears. I built that motor a bit more radical than this one and wish I could have put it on a dyno to see what the actual power output was. I had a Crane Fireball Cam (28428) in it. Lots of power for a heavy car. I still have the cam specification sheet I wish I still had the car.
Great video, Nick. I like to see dyno results in street trim, the manifolds that are installed on the car. With an exhaust system connected, we see diminishing differences between headers, and a free breathing stock "HO" exhaust manifold. These Pontiac engines with large valve heads (389 400, 421, and 455) produce very flat torque curves, and are extremely responsive on the street. By the time (some) other high performance engines develop horsepower, the Pontiac has already developed gobs of torque and horsepower, very quickly. it's not always all about max horsepower that an engine builds, it's how quickly it can build horsepower. Throttle response makes a car more drivable, a more exciting driving experience.
Love your in sit and content,im always tuned in ..love you nick and respect your Wisdom .
Nick, you are so right about them making you pay in other ways. Now we have to pay to import oil from halfway around the world, when we could get it in our backyard.
I tried to order a Lunati cam during the pandemic. Ended up going with something else because they were unfortunately very backlogged on orders. Can't wait to see the difference...watching now.
Great show Nick and Krew. Always learn some thing. Thanks for breaking it down barney style for us with hard heads!!!
Boy, with the color and carb, it looks identical to my wife's 77 TA 400.
Thank you, Nick and team
Thanks for watching, Futon.
Well that was a decent HP gain from basically a cam change. The 800 rochester I bet really didnt do anything for power over the 750 as long as the a/f ratios were the same. That motor doesnt need anymore than 750 cfm. About a 10 degree increase on intake and exhaust duration and a little more lift. You wouldnt want to go any bigger on the cam with the compression ratio at where it is. Basically you have a stock pontiac 455 with mild compression,stock flowing heads,stock intake and exhaust manifolds and a decent cam and made 395hp and over 500 trq.. Id say thats pretty good. Theres always more to be had with that motor like porting the heads but thats more time and money. You should be happy once its in the car,,,should really pin you in the seat!
Hey Nick ,George, and Krew , Good Morning to all . Love seeing the ol Tin Indian making noise and I fully agree with you Nick about the headers and putting it over 400 hp . Sure Good to start my day at your garage. Enjoy the dyno days too . I remember the earlier Pontiacs engines were painted a green color which had a sparkle to it and them using Wolf Head Oil back in those days . Nick ,do you remember what the green color was called for the earlier Pontiac engines ?
Early Pontiac engine color in the sixties was a Silver-Blue Metallic Color. Duplicolor has it. Engine Enamel.
@@nickpanaritis4122 Hey Nick , Thank-you for the reply . For some reason I was thinking it was a greener tint to it . But I knew you would have the correct answer . I like the earlier color on the Tin Indians, but I believe in doing the way it came from the factory and to specs . Thats one thing I love about how you do things ,there is no guessing, by the factory specs and attention to detail all the time . Do it right the 1st time . It was fun to see the 455 get its final test done and pretty good numbers too ...I'm now wanting to see what the early 50s Hemi you have in the shop will do when you get it done . I don't know who you have doing the block working and cleaning, but they sure have the old hemi block looking great . I truly enjoy all the dynos you do and the knowledge ,detail ,and the years of experience you show when doing them . Like I said before, you are a Master Master Mechanic hands down . Sorry for getting long winded Nick . Always a pleasure to talk with you and I very much appreciate your time Nick to respond to me . I know you are a Super Busy Man . God Bless you and your Family, and be safe . Best Regards.
@@OlSgtLove ..Always a pleasure and thanks for watching.
How the hell old are you? And it's CREW, SPELLED CREW! Damn foreigners
A&E nurse Steve Lioliopoulos on night shift tuned in from Adelaide Australia
Thanks for joining us, Steve. Don't forget the patients. :)
Good Morning Nick and Crew! Hope you all have a wonderful day!
Thanks. You too!
The price of fuel in Ontario todays is $ 8.30 per gallon or $1.83 per liter
Yep.. We are making the most of every trip.
We love the Pontiacs. Thank you. Maybe a tripower vs quadrajet, or stock 389 with and without Royal bobcat kit. GOOD SHOW !!
1.79 per liter here in Toronto Ontario Canada for regular diesel is 1.84 soon enough it's going to be 2 dollars per liter
The Pontiac 455 made decent power with the stock unported 1971 #96 400 Heads. #96 heads flow just 195 cfm @ 28 inches water Depression. So it was making 2 hp per 1.0 cfm intake flow with less than ideal 100% Volumetric efficiency of the 455 engine.
Not many other pushrod engines can do the same engine Parameters used.
@BrRe, using another Pontiac motor for comparison. In your opinion, is there advantages with the 428 over the 455? Respectfully referring to 1969 428 H.O. and the 1971 455 H.O. ?
@@kevinmanning4880 If you compare the 428 HO and 1971 455 HO engines 100 % Pure Stock built exact as Pontiac built them with 100% Original NOS GM parts the 428 HO will make more peak Hp at 390 Hp with 110 motor octane Race gasoline, high compression and high peak cranking and dynamic and effective compression ratio. Zero detonation Operation Full ignition advance used requirements met with modern Race fuel 110 octane.
The 1971 HO 455 is actually making a solid 350 Hp at the Flywheel on 91 octane gasoline what was Regular Fuel in 1971 year. Reports they run on 87 octane modern gasoline Ignition timing pulled back to 32 degrees BTDC No Vacuum advance used any.
The 1971 455 HO makes more torque rated at 480 ft/lbs. Its actually 510- 520 ft/lbs at the Flywheel.
The 1971 455 HO in a 1971 Pontiac Trans Am will Win the Street Drag Race.
Cylinder heads on the 1971 455HO Roundport exhaust are Superior over the 428 H0 D-port #16 & #62.
The 455 H0 engine intake ports flow more air a stronger entire flow curve .050" - .550" lift.
The Round port exhaust doesn't show all what it actually does on a flow bench but it moves more air Yes than most D-ports. Been proven measuring exhaust port flow on a flowbench a waste of time by many pros, Its not stimulating the exhaust energy present moving above the speed of sound, really best measured in Joules of Energy.
Superior Valve flow curtain on the 455 HO.
No doubt the 428 HO is still a Powerful street engine.
428 HO has a slightly better R/S rod to stroke ratio than a 455.
Makes less torque but was a Favorite of 1st Generation Firebird owners because they are traction limited unless they use Super Stock Drag Racing traction tricks or a Modern 4-link rear end layout.
2nd Generation Firebird Trans Am has the Superior Suspension best of any Pontiac ever built for Handling plus Street Drag Racing.
Both Fantastic engines and Legendary 428 HO and 455 HO.
Choose what you Love.
Everything changes when You Port Pontiac Iron or Aluminum Cylinder Heads. CNC machined doesn't give optimal results like many think.
Often fails on the streets and racetrack CNC Heads.
There is No Substitute for Hand Cylinder Heads and Intake Porting.
Very Difficult Skills to Learn and Apply. I do it learned from the Worlds Best Cylinder head Porters.
It's a Secret Club.
@@kevinmanning4880 Nothing helps promote easy to obtain torque and Hp Gains in a Pontiac V8 using 12.0:1 & 13.0:1 static compression ratios they become explosive Powerful. At 700 Hp + with Factory Pontiac Iron RAIV 614 Roundport heads. Been there done it Raced with.
Problem is 110 Motor octane gasoline is so expensive now.
Back in the day I was paying $2.99 per gallon for 110 octane a great deal now with gasoline 87 octane at $5 per gallon average. Canada where Nick is at much higher over $8 per gallon.
They make stellar power still on 91 -93 octane if planned carefully built for. Cylinder head Porting and intake Porting by hand required.
87 Octane be best to build for cruising duties long distances driven. Calculated on paper be down 40 Hp approximately over 91-93 octane.
Seems terrible to lose torque and Hp over 91-93 but advantages clearly there every time at the gas pump to fill up 16-20 gallons the Fuel Cell or Fuel tank.
12.0:1 - 13.0:1 Pontiac V8 worth +100 - + 200 Hp more depending upon design parameters of the entire engine. No cheeting octane required for them. Need 110-112 motor octane Race Fuel.
Or E85 or Methanol Alcohol Fuel.
@@brracing7861 much appreciate your valuable information. I've been a Pontiac enthusiast since 1985 at 17. Married, house kids, then divorce and destitute. Managed to hang on to my '70 GTO all these years. After blowing up a 428, I have another one, low mileage rebuild, looking for advice on what heads to swap to. I really like what you said about hand porting over "CnC porting". Didn't the 428 HO come with #48 heads? Would round port heads on a 428 make some advantages in powerband characteristics over the 455 or is it advantageous for the 455 over the 428? Just curious since the 428 is a square motor.