someone told us that in the mid west, every farm kid bought what their neighbor did, so one Z became a town full. Dads bought a caddy. We heard too that some gas farm equipment had HP stamped blocks , 3 tons had LT1 cranks in them
Really like Bill's explanation of cam timing/duration, according to cylinder head characteristics! Sometimes, less is more. Matched parts, is key. Bill, is super knowledgeable!
THIS is why I love this channel so much! He covers the things most hot rodders are curious about but no one has answered yet. When he said that the throat was at 95 percent I cringed but it did better than I thought it would. I learned about the valve to throat ratio probably less than ten years ago. Out of all the reading and research I’ve done on engines and cylinder heads I don’t recall the throat area ever being talked about much.
As someone who's dumped over $1000 (USD) into a set of GM "camel humps" for a 1970 LT-1 build....just buy the Trick Flow heads from Summit....They did a great job on those heads. The CnC ported Trick Flow "camel humps" flow serious air and the #1204 intake port will seal to a GM aluminum Hi-Rise intake....bigger sized ports #1205 or larger wont seal on a Z/28 hi-rise
Kind of the same theory, i built a 302 ford in 1984. I used 1970 351 w heads that i ported midly. Flat top piston, 500 lift cam. It made allmost 400 horsepower.
My world revolves around old Chevy's and the gen 1 SBC. I still own Bill Jenkins book, and many others from back in the days! The factory Chevy Power manuals are an invaluable resourse too. Great video content Allen Gold and Bill Little !!
Tons of useful info in the power manuals. Jenkins took it to the next level for what was proven to work with modification of the GM parts and did some wild stuff on the induction side. I used both back in the day. I built several big blocks back in the 80's using nothing but GM parts straight from the 60's manuals back when you could still get the parts and the power books and you couldn't beat the durability, everything was designed to work together and lived. Never had to guess what would work with what as long as you followed the recipe.
At Bill's glad he is starting at .050 very important as are sunken seats (used to hide overlap) or different valve angles. I first worked on 327 heads pre introduction in fall of 62 for the 452 (4 1/8 x 4 1/4) for the life of me I can't remember if we ran the new 327 heads or the fully modified 283 "fulie" heads.
Outstanding video! The technical information you provide on the science and rationale behind the decisions are excellent. I learn something new with each new video you post, Allan. A big shout out to Bill on sharing his wealth of knowledge and experience with us. The content, commentary, and editing in this video was fantastic. Thanks for sharing your knowledge and passion for engine building. I look forward to your next video.
I really enjoy your conversations and work done with Mr. Little. He is one of those men with so much knowledge a seasoned professional could learn more in three hours spent with him than a person could learn in three years working alone.
If I remember what I read in Grumpy's book many years ago the optimum rod length to stroke ratio wasn't a fixed quantity. It depended on the size of the cylinder head intake port and intake manifold, displacement and desired rpm range.
360 HP, 320 FT-LB, 15 in-hg. 10.5 CR, 7.11 DCR, 1.5 rockers. 286/294 adv, 0.525/0.510". 118/110 CL, Howards Flat Tappet Solid Headers, Heads Per Flow Bench BF240350 / BF248340 I think this meets all the project requirements and delivers the best power curve without high-ratio rockers or a roller cam.
Thank you so much for making and sharing this video = I have never seen this test done before! So much to learn about porting and air flow and cylinder heads. The engine is an air pump and there are so many factors involved with how an engine works!! Very interesting indeed!!!
So much great information and knowledge, applicable to not just SBC engines. I only hope the people who can really use and can learn from the knowledge offered here are watching and not just blindly hoping. grinding, polishing, potentially wasting time, money and power.
Keep up the great content! You do very good job creating interesting content.Thanks for keeping the videos interesting. I always can’t wait for the next one. Thanks to Bill for his expertise. Thanks to Golds garage!
Great episode! I've only recently discovered your channel and subscribed. I like that you're talking about the history of how the Z28 302 came about. I learned most of what I know about head porting and engine building from my library of books from the greats like Jenkins, Vizard, Smokey and many others. I've probably been building engines and porting my own heads for 45 years now. My first head porting experience was on a set if camel humps that I still have. The first thing I did before doing any porting was to study aerodynamics and airflow to see how air reacts to the various shapes and read everything I could find about heads, porting and what not to do. Often you'll be surprised at how suddenly the airflow diminishes because some of it will move in a way or take a path that disrupts the rest because of a badly shaped port. Also, in a small C.I. engine air velocity is just as important as flow is in making power and why sometimes a smaller port can make more power. These same principles of aerodynamics and fluid dynamics can be used inside the engine crankcase to improve oil flow, oil return or airflow within the crankcase, allowing those elements to move more freely. Pistons displace the air underneath them as they move up and down, the crank itself moves air and oil as it spins, modifications can be done to improve their ability to move freely, which can benefit horsepower and economy.
Great video content. I always tought the flow had to go like a waterslide. Not like a pinball machine. There is sooo many factors to check like clearly explained by experts here. The balance between FLOW/PRESSURE/VELOCITY IS ALL CALCULATED WITH YOUR APPLICATION. Im no expert. Actualy Im a nurse who know more about the importance of a healthy body to keep all the vitals within the specs. If your running a marathon, you want good low RPM torque. If you sprint the 100m. You need the max high flow to feed the muscle as fast as possible. It's exactly basicaly the same principles as a engine. If you push it too much, it breaks. And any engines that it brand new eventualy worn down gradualy. Even the best builders know racing is hard on the components. Carbon and bad fuel mix clogs the flow little buy little. The main thing is that you love what you do to make it the best you can. Money as nothing to do with proudness. It pays only the bills. Not the soul. Dont forget your dealing with the engineers creations and making it better!❤
Good explanation, my daughter in law is a dietitian and she's always at me to stay healthy just like an engine, I think we could learn from each other, but it doesn't seem to happen, thanks
I didn't think a 205 intake valve would fit, and lesve enough metal between the exhaust valve. We never went psst 202, but then I'm no expert on such things, and I haven't messed with anything like that in a long long time. But I do love a 327, with all the right pieces, and 302 sound real sweet between 5,000 to 6,800 rpms. Nice to see some folks that still appreciate the little mouse motors, and believe in what they're capable of doing in the hands of the right person
Great test! Are you going to show the numbers after Bill fixes them? Im sure he doesn't want to give away sscrets, but the numbers would be neat to see. Thanks !
10:15 Rod ratio, or rather optimum rod ratio, is folklore. If you build an engine with excellent heads and cam, compression, etc. and an identical one with a 0.250" longer rod any power difference is going to be in the range of margin of error for the dyno.
Thank you. I'm guessing that my heads will flow similarly. I'm using the Chevy Performance 492 camel hump heads with .202 intake valves and .160 exhaust, and 18 degree angle milled to 51.5 cc chambers. They have not been ported.
I have ported many heads, and plenty of them were cast iron. Monotonous yes, dirty yes, time consuming yes. You should wear protective gear not only for your eyes but also your lungs and ears. I know ! Working in a set of Aluminum heads now for a client.
A Ton of Good Data from this.... Im very curious about the TF New AL Double Hump 175 cc's... I've been considering adding these to my L79 vs. porting the Original '461 w/ 2.02/1.6 valves.
Thanks for the question. The TF heads work pretty well. Unless you have to keep the L79 authentic and original, I would go with them. You can always paint them.AG
I have a set of untouched 3890462 camel heads but the casting also says CANADA under the serial number. Never seen the CANADA casting before. I am in the states, is this common in Canada? I am only saving them in case someone needs them for a restoration. Anyone know if they are worth holding onto?
Thanks Kash. I have never seen that myself, however at that (1969 era) time GM had a foundry in St. Catherine's Ontario Canada. I visited it in 1969 and they did cast cylinder heads there. AG
Alan and Bill. Good job, excellent viewing. just a quick question. Bill you are an expert, you take 40 hrs to do iron heads. Is it possible to see a good improvement doing it as a novice and no flow bench if conservative. obviously get a valve job with intake back cut at machine shop. love watching you guys. Was surprised about the Ford too.
I have a fall 66 327 two bolt small journal block for the first new model year for the 66, 67 Camaro it's .030 already and someone put a Mallory balanced 283 steel crank in it to build a 302 + .030
I’m building a new engine for my 68 RS/SS Camaro and keeping the original on a stand becuase I don’t want to risk blowing it up and I’m building a sbc much to hot to risk on the matching numbers block that’s low mileage under 100k
I see I just read an article about canted valve heads used by Smokey Yunic DZ 302. I guess the production cars came with the old camel hump . Thank you for getting back to me.
there is no need to compare heads. Eric Weingartner has already done every head out there cast and alum. on a flow table and Dyno with numerous intakes and spacers and carbs and has all the graphs here on YT.
Nothing against Eric and his videos as I watch them often but Bill knows what he is doing with a set of heads. I have set of Vortec heads with 1.94/1.50 valves that Bill ported 20 years ago and they out flow what I see on Eric's videos. That being said, im sure Bill has learned much more in the past 20 years.
This is a gem of a channel AG
That’s what I say also!
@@robertwest3093 mr little is a god too
Thanks Guys. We will keep digging. AG
someone told us that in the mid west, every farm kid bought what their neighbor did, so one Z became a town full. Dads bought a caddy. We heard too that some gas farm equipment had HP stamped blocks , 3 tons had LT1 cranks in them
You don't find them any longer as the old cores have all but dried up, but you'd be amazed at what engine cores you could find steel cranks in.
interesting comment, thanks for sharing.AG
Really like Bill's explanation of cam timing/duration, according to cylinder head characteristics! Sometimes, less is more. Matched parts, is key. Bill, is super knowledgeable!
For sure, thanks for watching and commenting.AG
THIS is why I love this channel so much! He covers the things most hot rodders are curious about but no one has answered yet. When he said that the throat was at 95 percent I cringed but it did better than I thought it would. I learned about the valve to throat ratio probably less than ten years ago. Out of all the reading and research I’ve done on engines and cylinder heads I don’t recall the throat area ever being talked about much.
Thanks for your comments as always Robert. AG
i have a few Cheve books from Bill Jenkins and Davis Vizard from the 70's, amazing stuff
Thanks Jim, I am rereading the Jenkins book now. Compared to these guys, we are just tinkering.AG
As someone who's dumped over $1000 (USD) into a set of GM "camel humps" for a 1970 LT-1 build....just buy the Trick Flow heads from Summit....They did a great job on those heads. The CnC ported Trick Flow "camel humps" flow serious air and the #1204 intake port will seal to a GM aluminum Hi-Rise intake....bigger sized ports #1205 or larger wont seal on a Z/28 hi-rise
Thanks EJ. I have used the Trick Flow heads before, they do work well. AG
Kind of the same theory, i built a 302 ford in 1984. I used 1970 351 w heads that i ported midly. Flat top piston, 500 lift cam. It made allmost 400 horsepower.
Thanks Glenn, the Boss 302 was an iconic engine also. AG
My world revolves around old Chevy's and the gen 1 SBC. I still own Bill Jenkins book, and many others from back in the days! The factory Chevy Power manuals are an invaluable resourse too.
Great video content Allen Gold and Bill Little !!
Tons of useful info in the power manuals. Jenkins took it to the next level for what was proven to work with modification of the GM parts and did some wild stuff on the induction side. I used both back in the day. I built several big blocks back in the 80's using nothing but GM parts straight from the 60's manuals back when you could still get the parts and the power books and you couldn't beat the durability, everything was designed to work together and lived. Never had to guess what would work with what as long as you followed the recipe.
Great comments, thanks guys. AG
David Vizzard ported the double humps, they out flowed AFR after market heads
I wonder which number heads DV used, pretty sure I have seen that video already though..
No way…
Thanks for the info Daniel.AG
At Bill's glad he is starting at .050 very important as are sunken seats (used to hide overlap) or different valve angles. I first worked on 327 heads pre introduction in fall of 62 for the 452 (4 1/8 x 4 1/4) for the life of me I can't remember if we ran the new 327 heads or the fully modified 283 "fulie" heads.
Great info, thanks Jm.AG
This is such a wonderful channel. Knowledge and experience. Thanks to both of you!
Thanks Michael. AG
Outstanding video! The technical information you provide on the science and rationale behind the decisions are excellent. I learn something new with each new video you post, Allan. A big shout out to Bill on sharing his wealth of knowledge and experience with us. The content, commentary, and editing in this video was fantastic. Thanks for sharing your knowledge and passion for engine building. I look forward to your next video.
Thanks Todd, looking forward to see you on the 13th. Your 389 is patiently waiting. AG
I really enjoy your conversations and work done with Mr. Little.
He is one of those men with so much knowledge a seasoned professional could learn more in three hours spent with him than a person could learn in three years working alone.
Great comment, thanks Hugh.AG
If I remember what I read in Grumpy's book many years ago the optimum rod length to stroke ratio wasn't a fixed quantity. It depended on the size of the cylinder head intake port and intake manifold, displacement and desired rpm range.
I concur, and from my memory Allen Gold's numbers are accurate to the book.
thanks for watching and commenting guys.AG
@@goldsgarage8236 You're quite welcome. I really enjoy your channel.
360 HP, 320 FT-LB, 15 in-hg.
10.5 CR, 7.11 DCR, 1.5 rockers.
286/294 adv, 0.525/0.510".
118/110 CL, Howards Flat Tappet Solid
Headers, Heads Per Flow Bench
BF240350 / BF248340
I think this meets all the project requirements and delivers the best power curve without high-ratio rockers or a roller cam.
Sounds like a good combination, thanks Shane. aG
Thank you so much for making and sharing this video = I have never seen this test done before! So much to learn about porting and air flow and cylinder heads. The engine is an air pump and there are so many factors involved with how an engine works!! Very interesting indeed!!!
Thanks for the comment 4speed. AG
*The camel heads are still good but with the right hands doing the work on them!! Good work fellas !!*
Thanks you Doctor. We were very pleased with the results.AG
Nice to hear you say zed instead of zee too, thanks.
Thanks for the comment Victor. AG
@Bill Little G 50:06 ood stuff! Anxious to see what they flow with 2.05 and good seat work
I also have a steel 3 in stroke small journal crank with the round flange with the notch like those DZ big journal cranks
Thanks Eric, I think the small journal forged cranks would be quite rare now. .AG
The 291 casting double humps on my shop truck flow: 201 @ 300 lift, and 260 @ .600 lift @ 28 inches. 2.050/1.60 valves.
Those are very good numbers Vortec. AG
So much great information and knowledge, applicable to not just SBC engines.
I only hope the people who can really use and can learn from the knowledge offered here are watching and not just blindly hoping. grinding, polishing, potentially wasting time, money and power.
Good point Marcus. AG
Well this is certainly very cool.
We get to witness a (Swirl Meter)
Swirl improves low end torque
Keep up the great content! You do very good job creating interesting content.Thanks for keeping the videos interesting. I always can’t wait for the next one. Thanks to Bill for his expertise. Thanks to Golds garage!
Very nice comment, thanks for watching. AG
Great episode! I've only recently discovered your channel and subscribed. I like that you're talking about the history of how the Z28 302 came about.
I learned most of what I know about head porting and engine building from my library of books from the greats like Jenkins, Vizard, Smokey and many others.
I've probably been building engines and porting my own heads for 45 years now. My first head porting experience was on a set if camel humps that I still have. The first thing I did before doing any porting was to study aerodynamics and airflow to see how air reacts to the various shapes and read everything I could find about heads, porting and what not to do. Often you'll be surprised at how suddenly the airflow diminishes because some of it will move in a way or take a path that disrupts the rest because of a badly shaped port. Also, in a small C.I. engine air velocity is just as important as flow is in making power and why sometimes a smaller port can make more power. These same principles of aerodynamics and fluid dynamics can be used inside the engine crankcase to improve oil flow, oil return or airflow within the crankcase, allowing those elements to move more freely. Pistons displace the air underneath them as they move up and down, the crank itself moves air and oil as it spins, modifications can be done to improve their ability to move freely, which can benefit horsepower and economy.
Thanks so much for your comments Bob. You have given this subject a lot of detailed thought. Thinking is harder than working, so good for you. AG
Incredible presentation learned volumes today thank you
Thanks for watching Thomas.AG
Keep feeding the videos !!!!!
Thank You AG & Bill
Very good information
Thank you for taking the time to share info like this
We will, more to come, thanks Nerrad.AG
Great video content. I always tought the flow had to go like a waterslide. Not like a pinball machine. There is sooo many factors to check like clearly explained by experts here.
The balance between FLOW/PRESSURE/VELOCITY IS ALL CALCULATED WITH YOUR APPLICATION.
Im no expert. Actualy Im a nurse who know more about the importance of a healthy body to keep all the vitals within the specs. If your running a marathon, you want good low RPM torque. If you sprint the 100m. You need the max high flow to feed the muscle as fast as possible.
It's exactly basicaly the same principles as a engine. If you push it too much, it breaks. And any engines that it brand new eventualy worn down gradualy. Even the best builders know racing is hard on the components. Carbon and bad fuel mix clogs the flow little buy little.
The main thing is that you love what you do to make it the best you can.
Money as nothing to do with proudness. It pays only the bills. Not the soul.
Dont forget your dealing with the engineers creations and making it better!❤
Good explanation, my daughter in law is a dietitian and she's always at me to stay healthy just like an engine, I think we could learn from each other, but it doesn't seem to happen, thanks
That is a great analogy, great comment. Thanks dada. AG
Great information, you should look each way when going through traffic light intersections though.
OK, got it. thanks. AG
😊 I know it's none of my business, I'd hate to see you tee boned, that all.
Thanks for all the effort in the video making. Good guys and good info!
Very nice!, thank you. AG
Great content! I enjoy all of your videos!!!Keep up the great work!!
Thanks Darren. AG
Tony's and 302 small blocks go together like peas and carrots. I've had a couple and about to build another one soon.
Great video, thanks!
Thanks Tony! AG
I didn't think a 205 intake valve would fit, and lesve enough metal between the exhaust valve.
We never went psst 202, but then I'm no expert on such things, and I haven't messed with anything like that in a long long time.
But I do love a 327, with all the right pieces, and 302 sound real sweet between 5,000 to 6,800 rpms.
Nice to see some folks that still appreciate the little mouse motors, and believe in what they're capable of doing in the hands of the right person
Thanks Timothy, the 327 was my favorite engine growing up and still a sentimental favourite.AG
Thank you for your knowledge and videos
Thanks for watching and commenting Patrick. AG
I agree with Bill the 95% intake port needs a 2.05 to fix it.
Good point, thanks Don.AG
Thanks guys
Thanks for watching and commenting Bill. AG
Thank you for sharing your wisdom gentleman 🥰
Thanks for watching and commenting Mike.AG
Learned so much last time from Bill glad you went back😊
Me too, thanks Laurence.AG
Great test! Are you going to show the numbers after Bill fixes them? Im sure he doesn't want to give away sscrets, but the numbers would be neat to see. Thanks !
Thanks Mike, we plan to do that so watch for it. AG
10:15 Rod ratio, or rather optimum rod ratio, is folklore. If you build an engine with excellent heads and cam, compression, etc. and an identical one with a 0.250" longer rod any power difference is going to be in the range of margin of error for the dyno.
Good point, thanks Yarrda. AG
I can't do it in 40. Workin on it.
A lot of work for sure, thanks Les. AG
Thank you for your channel. You do a great job!
Nice comment, thanks Mark. AG
Thank you. I'm guessing that my heads will flow similarly.
I'm using the Chevy Performance 492 camel hump heads with .202 intake valves and .160 exhaust, and 18 degree angle milled to 51.5 cc chambers. They have not been ported.
Thanks for the comment, that is a lot of milling.AG
I have ported many heads, and plenty of them were cast iron. Monotonous yes, dirty yes, time consuming yes. You should wear protective gear not only for your eyes but also your lungs and ears. I know ! Working in a set of Aluminum heads now for a client.
All good points, thanks Comet. AG
A Ton of Good Data from this.... Im very curious about the TF New AL Double Hump 175 cc's... I've been considering adding these to my L79 vs. porting the Original '461 w/ 2.02/1.6 valves.
Thanks for the question. The TF heads work pretty well. Unless you have to keep the L79 authentic and original, I would go with them. You can always paint them.AG
Good info thanks
Thanks Luke. AG
I've worked on quite a few Z28's, is it a Canadian thing to call them a ZED28? Never heard of this before
Thanks Robert, one of the few differences between the US and Canadian version of the English language. AG
I have a set of untouched 3890462 camel heads but the casting also says CANADA under the serial number. Never seen the CANADA casting before. I am in the states, is this common in Canada? I am only saving them in case someone needs them for a restoration. Anyone know if they are worth holding onto?
Thanks Kash. I have never seen that myself, however at that (1969 era) time GM had a foundry in St. Catherine's Ontario Canada. I visited it in 1969 and they did cast cylinder heads there. AG
Alan and Bill. Good job, excellent viewing. just a quick question. Bill you are an expert, you take 40 hrs to do iron heads. Is it possible to see a good improvement doing it as a novice and no flow bench if conservative. obviously get a valve job with intake back cut at machine shop. love watching you guys. Was surprised about the Ford too.
Bill, can you reply to this please? AG
Good Video Informative.
Thanks for watching and commenting Allan.AG
Very interesting but shouldn't the flow on the exhaust port be performed through the valve side the way the actual exhaust gasses flow?
Bill Little, can you please respond to this question.AG
I have a fall 66 327 two bolt small journal block for the first new model year for the 66, 67 Camaro it's .030 already and someone put a Mallory balanced 283 steel crank in it to build a 302 + .030
Thanks for the info Eric.AG
good info
Thank you Jim, AG
I have a mid-'67 Camaro 327 if it would help you in your block search. Casting 3892657, date F207, stamped V0628MA. Very reasonable.
Thanks Yoda, i will pass it on.AG
Good stuff guys.
Thank you Phil. AG
My new engine will have a 4.610" bore × 3.76" stroke with 6.535 rods.
I love that combo, unshroud the valves, short stroke more rpm more hp, your right on.
@@billlittle4285 Chamber has been ported 👍🏻
I’m building a new engine for my 68 RS/SS Camaro and keeping the original on a stand becuase I don’t want to risk blowing it up and I’m building a sbc much to hot to risk on the matching numbers block that’s low mileage under 100k
Good idea, thanks Thumper. AG
?Are you saying zed28?
Thanks for the question Bigwheel. Just the Canadian pronunciation.AG
I thought the real dz 302 had hemi heads?
Thanks for the comment Ken. Actually the DZ used the so called Fuel Injection heads from the Corvette engine.
I see I just read an article about canted valve heads used by Smokey Yunic DZ 302. I guess the production cars came with the old camel hump . Thank you for getting back to me.
WTF is a ZED28??
Z/28 - Is a model of Camaro.
@@yarrdayarrdayarrda : I know that. I've owned two of them. My question was; what is a ZED 28?
It's Canadian eh!!
You driving a Ford truck? I thought you were a Chevy Guy. 🙂
🤣
Thanks Allan. I have had both chevy and Ford trucks over the years. Both served me well. AG
There cheaper lol.
It was good to see he made to Bill's shop!
@@alleyoop1234 barely we had to push it to get it started when he e left lol
there is no need to compare heads. Eric Weingartner has already done every head out there cast and alum. on a flow table and Dyno with numerous intakes and spacers and carbs and has all the graphs here on YT.
Nothing against Eric and his videos as I watch them often but Bill knows what he is doing with a set of heads. I have set of Vortec heads with 1.94/1.50 valves that Bill ported 20 years ago and they out flow what I see on Eric's videos. That being said, im sure Bill has learned much more in the past 20 years.
The more the content the better, no?
318 and 340 have same stroke...302 worked better in a mid 60's bonneville build with longer rod, shorter lighter piston, roller cam, hilborn injection
Thanks for the comment Jm. AG
The T/A mopar was better.
Thanks Karl. AG
Why are you driving a Ford?
Watch for the answer in future videos. AG
Sorry Mr.Gold ... I'll have to unsubscribe...youre driving a Ford truck 😢
🤣
He needs that aluminum body up north.
Good point. The aluminum body was a factor in this one. AG
Hahahaha..Lmao !!!
I see lots of aluminum ford's with bigger rust hoels than steel 😂