I think theres a bit more to it than that, although it may be a starting point. Theres so many factors that come into play that a simple conclusion cant always be drawn by two lines crossing. Daily driver, some fun driving, 1/8 mile or 1/4 mile, launch style "will it hook up". There may be a time when you actually design in for a smaller turbo or budget constraints. I have two s480 but the ar is 1.1 and the size is straight 80 mm, cheap chinese, dont expect amazing things from them but its powering a 6k vehicle and 37" tires. I wont be spinning it 65-7000 rpm so I opted for smaller wheel size for quicker spool at lower rpm, back pressure is not too much a concern for me but a single big turbo would not be fun on a 98 k1500 suburban.
@@daveb1870 Good stuff. I agree you can't select a turbo based on one parameter...especially when you don't know the pressure ratio between the intake and exhaust until it's already been installed. I still believe it's a good indicator of whether the turbine wheel and a/r are matched well with the compressor.
Hey Richard, thanks for showing these 2 different turbos back to back. Even tho this was a smaller 4.8L and my setup will be a good bit larger 408/6.7L for my Durango, it shows the HP potential of each turbos, more so the T45 than the larger S475, and the associated back pressure for each up through the power levels
Im looking at these True North Turbos. Kyle(Boosted Lifestyle) told me they offer a 76mm compressor on a 103 back side. For the price, they seem like a great frame that keeps backpressure down and has plenty of compressor for big power setups without sacrificing a ton of boost response.
Thank you Richard for providing more details about the turbo specs (a/r turbine housing, flanges, compessor and turbine dimensions). This helps a lot. It's an excellent test with lots of feedback. The S475 seems ideal for a 4.8 lt engine (so most likely any other engine in the 4.8lt - 5.0 lt range) while the GT45 seems more ideal for something like a L99 or even 3.8 lt, something like this.
@@richardholdener1727 I think going for 700-800 whp in a 4.8 lt is a fair target.The GT45 (or a similar sized turbo) would make sense only if it's building more boost below 3000 rpm, which is not shown in the graph. By the way I like the choice of the S475 for this test. It's a relatively cheap, journal bearing turbocharger with a cast compressor which seems suitable for the application.
I would like to see one that shows What happens when your Turbo is too big and you start losing power on the bottom versus using a bigger Turbo for what it's rated for
You should show backpressure + boost + and add on EGT and dyno load. There's a lot of mystique out there for the guys who want to take their 5.3 chevy 1500 and put a turbo on it, but still pull a 4k boat. Personally, I just put diesel in the tank instead of gas when I want to do this, but some folks can't afford that luxury and want both.
@@richardholdener1727 A measurement of absorber load, water brake, etc. I think it's inertia factor? I don't remember, it's been a while since I messed with an engine dyno.
Your videos are great. You give so much accurate info compared to so other channels here on TH-cam. Any chance do doing a video on Ford tour cylinder head porting ("B" and "C" heads). There isn't much out there that shows where and how much if you know that I mean. It would be great if you could. P.S. Any chance you can help out a disabled out of work auto tech. I have a 0.060 over CHEVY 350 (gen 1) short block I having been trying to build for my wife's car. I has hoping you or all the people you know might have a few pair of ready to go heads collecting dust. I have been trying to scrape together funds but it real difficult with in income. So, do you have a pair of heads that can go into this 350(360 cid). It would be going into my wife's '79 Vette. Any help would be appreciated. Not looking to build anything crazy, just about 400hp. Thanks for all the invaluable info.
Great video Mr. Richard-love all the data! Response rate is perimont, for me, however what's the tradeoff between response & back pressure-is a high delta of back pressure vs boost detrimental to an engine? Thank you Tony
High back pressure can cause broken turbo shafts for one, or over speeding the turbo to the point wheels explode. Probably won't happen on a street car though. Excessive pressure anywhere is hard on parts and creates heat.
@@stevecobratei8538 that was back in the 80s though new technology would make a big different…I know a guy that did it with a coyote and it was pretty badass
seeing quite a few import guys running cummins takeoff turbos (hx35, hy35, he351) on relatively small displacement (2L-ish) gas engines. How do these compare to a properly sized cxracing or other budget turbos? seems the reason for the second hand holset is usually budget driven but is there a better option for the money?
@@richardholdener1727 makes sense, i just learned this and it seemed kinda counterintuitive (big slow diesel compared to small high revving engine) i was sure there was some sort of secret sauce but i 100% understand being cheap.
@@travisabrahamson5092 compressor side should be plenty to make 500hp on a single 351 but the problem i can see would be the diminutive turbine housing at 9cm. it is a more efficient housing than the earlier hx35 12cm or the hy35 9cm housing but on a gas engine to spin the compressor hard enough to make real power i think you'd need a significantly larger housing to not have choking issues from backpressure. Going to twin he351's i bet it would spool great and have enough exhaust flow to not choke but then i think your compressors would be too low in their map to be efficient. Definitely not an expert but i've done a lot of turbo shopping lately and the he351 is appealing but i think it may be a touch missmatched on turbine to compressor sizing to be good as single or doubles on a small LS. Might look into a pair of the cummins takeoff hx35's for a more balanced compressor/turbine combo and a larger cross-section area to help keep backpressure down. or a summit s475 would flow more than you'd ever need, be properly sized and be pretty cheap with warranty.
I'd like to see an NA engine run with open exhaust, then choke the exhaust down to various back pressures. This would give us an idea of how much horsepower it takes to spin the turbo.
I have a 302 in my pinto Drag Car . 2550lbs it run a 6.52 1/8 mile 1.45 60ft . 103 mph . On vp110 gas . I have been thinking about Switching to e85 . I was told I would gain 2 to 3 tens in the 1/8 ? what do you think . I all so jus bought a 1 TRB-TO4E Turbo Charger .50 AR Compressor , .63 AR Turbine , 5 BOLT Exhaust , 3" Inlet & 2" Outlet . What do you feel My Horse power Gains would Be Thanks
Sooooooo badly wanted to see what that s475 would have done at about 25-30psi. Why don't you ever turn things up where you really can learn the limits of the good turbos?
@@richardholdener1727 well the compressor would run out at some point (long before the turbine) and we'd love to know what point that is! Appreciate the videos🤘
What about twin DNA GT 45s on a 5.3 LS? What do you think the response rate to back pressure ratio would be? The mindset here is that everything is better with twins ;). Not to mention power to costs.
I bought a smaller turbo s300 66mm .91 a/r supposed to but good up to 800hp. 750hp being the higher end of my goals.(gonna start with 500ish hp until I get a 4l80) I have a 6.0 lq9. I bought a 76mm because I was afraid the 66mm would be too small. Do you have a video on turbos that are too small for an engine and what's at stake? And what kinda changes are made with the tune when changing different size turbos?
The rings are gapped just need to weld up an oil return on the oil pan and I can get it back in the truck. Trying to figure what to expect when it comes time to tune.
@@richardholdener1727 I know if you put to much cam the engine run rough but if you put bigger rocker ratio will te engines run smother for the same lift?
Dude, I like your videos as they are very informative. But, please when you are talking about a subject with pictures, stay on the pictures so we can get a better look. You flash pics and go back to you talking. You're not ugly but the content, not you talking and only flashes of content. Hope I said it nice enough, not trying to upset you.
I'm getting so many mixed reviews, anyone on here know how much boost I can run on a 10:1 static 7.75ish:1 dynamic? PUMP 92 ONLY. Some people say 12lbs some say 5. It's a turbo car.
@@richardholdener1727 Thank you very much, the LS forums are all over the place with their answers. I was just trying to give as much info as possible. Going to try to run 10psi on my s480, I know that's baby boost for the s480 but I made a mistake.. lol
@@KreatorOfDeath1985 I made a mistake when buying my turbo too.I bought a s475 when I thought I was getting a s480. It's still in the box, my project has stalled for a minute.
Great analysis. I especially like seeing the intake/exhaust pressure data. Knowing where they cross 1:1 seems to say a lot about the sizing.
I think theres a bit more to it than that, although it may be a starting point. Theres so many factors that come into play that a simple conclusion cant always be drawn by two lines crossing.
Daily driver, some fun driving, 1/8 mile or 1/4 mile, launch style "will it hook up".
There may be a time when you actually design in for a smaller turbo or budget constraints.
I have two s480 but the ar is 1.1 and the size is straight 80 mm, cheap chinese, dont expect amazing things from them but its powering a 6k vehicle and 37" tires. I wont be spinning it 65-7000 rpm so I opted for smaller wheel size for quicker spool at lower rpm, back pressure is not too much a concern for me but a single big turbo would not be fun on a 98 k1500 suburban.
@@daveb1870 Good stuff. I agree you can't select a turbo based on one parameter...especially when you don't know the pressure ratio between the intake and exhaust until it's already been installed. I still believe it's a good indicator of whether the turbine wheel and a/r are matched well with the compressor.
I’m all about response rate. I like the instant torque.
It’s like getting salsa at a new restaurant. Start mild and move up from there.
GREAT VIDEO RICHARD!!!!! I LEARNED SO MUCH!!!!! THANKS FOR SHARING!!!!!
Hey Richard, thanks for showing these 2 different turbos back to back. Even tho this was a smaller 4.8L and my setup will be a good bit larger 408/6.7L for my Durango, it shows the HP potential of each turbos, more so the T45 than the larger S475, and the associated back pressure for each up through the power levels
Love the education I'm getting. Love your content.
Im looking at these True North Turbos. Kyle(Boosted Lifestyle) told me they offer a 76mm compressor on a 103 back side. For the price, they seem like a great frame that keeps backpressure down and has plenty of compressor for big power setups without sacrificing a ton of boost response.
Thank you Richard for providing more details about the turbo specs (a/r turbine housing, flanges, compessor and turbine dimensions). This helps a lot. It's an excellent test with lots of feedback. The S475 seems ideal for a 4.8 lt engine (so most likely any other engine in the 4.8lt - 5.0 lt range) while the GT45 seems more ideal for something like a L99 or even 3.8 lt, something like this.
the S475 is only ideal for the 4.8L if you want 1000 hp (or above 700 hp)
@@richardholdener1727 I think going for 700-800 whp in a 4.8 lt is a fair target.The GT45 (or a similar sized turbo) would make sense only if it's building more boost below 3000 rpm, which is not shown in the graph. By the way I like the choice of the S475 for this test. It's a relatively cheap, journal bearing turbocharger with a cast compressor which seems suitable for the application.
Just what I needed 👌
👀👀👀yep get the summit and turn it to 18psi
@@infamousnova you already got the s475, why you watching this?? Lmao
@@NightWrencher lol. Im here for the show. Richard always got good info. Im waiting to see 2 builds
I would like to see one that shows What happens when your Turbo is too big and you start losing power on the bottom versus using a bigger Turbo for what it's rated for
It wont "loose " power - it'll just produce NA power until a point where the turbo starts to produce positive boost pressure in the RPM range...
It just kicks in later in the rpm doesn’t lose power at all but when it lights up small turbos look weak compared to big turbos
You should show backpressure + boost + and add on EGT and dyno load. There's a lot of mystique out there for the guys who want to take their 5.3 chevy 1500 and put a turbo on it, but still pull a 4k boat. Personally, I just put diesel in the tank instead of gas when I want to do this, but some folks can't afford that luxury and want both.
dyno load?
@@richardholdener1727 A measurement of absorber load, water brake, etc. I think it's inertia factor? I don't remember, it's been a while since I messed with an engine dyno.
S400’s for the win! Great chargers for not a lot of money
Your videos are great. You give so much accurate info compared to so other channels here on TH-cam.
Any chance do doing a video on Ford tour cylinder head porting ("B" and "C" heads).
There isn't much out there that shows where and how much if you know that I mean.
It would be great if you could.
P.S.
Any chance you can help out a disabled out of work auto tech.
I have a 0.060 over CHEVY 350 (gen 1) short block I having been trying to build for my wife's car.
I has hoping you or all the people you know might have a few pair of ready to go heads collecting dust.
I have been trying to scrape together funds but it real difficult with in income.
So, do you have a pair of heads that can go into this 350(360 cid). It would be going into my wife's '79 Vette.
Any help would be appreciated. Not looking to build anything crazy, just about 400hp.
Thanks for all the invaluable info.
I don't think I have an SBC heads laying around right now
Love your videos, really just tell it as it is. I’m curious as to two gt45 vs one big turbo
it would take a big single turbo to equal twin gt45s (1400-1500 hp capable)
Great video Mr. Richard-love all the data! Response rate is perimont, for me, however what's the tradeoff between response & back pressure-is a high delta of back pressure vs boost detrimental to an engine? Thank you Tony
high back pressure can cause problems
High back pressure can cause broken turbo shafts for one, or over speeding the turbo to the point wheels explode. Probably won't happen on a street car though. Excessive pressure anywhere is hard on parts and creates heat.
I would like to see draw through vs blow through turbo set up
how would you plumb the intercooler setup on draw through?
@@scottleggejr you would not need a inner cooler with a draw through
Have you ever seen a 1980/ 1981 Turbo Tran Am? That's to blow thru system
Sorry its suck thru. Carb feeds turbo
@@stevecobratei8538 that was back in the 80s though new technology would make a big different…I know a guy that did it with a coyote and it was pretty badass
Intro music causes immediate hip thrusting action
seeing quite a few import guys running cummins takeoff turbos (hx35, hy35, he351) on relatively small displacement (2L-ish) gas engines. How do these compare to a properly sized cxracing or other budget turbos? seems the reason for the second hand holset is usually budget driven but is there a better option for the money?
the HX series work well-just so cheap to get new ones
@@richardholdener1727 makes sense, i just learned this and it seemed kinda counterintuitive (big slow diesel compared to small high revving engine) i was sure there was some sort of secret sauce but i 100% understand being cheap.
@@richardholdener1727 I have 2, Holeset H1Cs from a couple 5.9 Cummins school buses. Do you think they would work okay with a 350 or 383 SBC ?
I would like to know about this aswell.
I want to use this holset he 351s on a 4.8 or 5.3
@@travisabrahamson5092 compressor side should be plenty to make 500hp on a single 351 but the problem i can see would be the diminutive turbine housing at 9cm. it is a more efficient housing than the earlier hx35 12cm or the hy35 9cm housing but on a gas engine to spin the compressor hard enough to make real power i think you'd need a significantly larger housing to not have choking issues from backpressure. Going to twin he351's i bet it would spool great and have enough exhaust flow to not choke but then i think your compressors would be too low in their map to be efficient. Definitely not an expert but i've done a lot of turbo shopping lately and the he351 is appealing but i think it may be a touch missmatched on turbine to compressor sizing to be good as single or doubles on a small LS. Might look into a pair of the cummins takeoff hx35's for a more balanced compressor/turbine combo and a larger cross-section area to help keep backpressure down.
or a summit s475 would flow more than you'd ever need, be properly sized and be pretty cheap with warranty.
Try it on a v10 bet the summit turbo would be destroying the ebay turbo in every curve gales been playing with them since last year
below 700 hp, the GT45 does well-back pressure will be higher on the larger v10
I'd like to see an NA engine run with open exhaust, then choke the exhaust down to various back pressures. This would give us an idea of how much horsepower it takes to spin the turbo.
it doesn't work that way
I have a 302 in my pinto Drag Car . 2550lbs it run a 6.52 1/8 mile 1.45 60ft . 103 mph . On vp110 gas .
I have been thinking about Switching to e85 .
I was told I would gain 2 to 3 tens in the 1/8 ?
what do you think .
I all so jus bought a 1 TRB-TO4E Turbo Charger
.50 AR Compressor , .63 AR Turbine ,
5 BOLT Exhaust , 3" Inlet & 2" Outlet .
What do you feel My Horse power Gains would Be
Thanks
Gains depending on boost level.
Why use such a small frame charger?
what size is that turbo? also gains on na motor minimal unless very high compression
Can you make either one of these for draw through
Think you have the first turbos specs back to front.
You got a back Pressure test with twin turbos to a single. Nd possibly a bigger single
yes
I'll look thanks
Sooooooo badly wanted to see what that s475 would have done at about 25-30psi. Why don't you ever turn things up where you really can learn the limits of the good turbos?
THAT S475 WON'T SUPPORT 30 PSI ON THIS MOTOR
@@richardholdener1727 well the compressor would run out at some point (long before the turbine) and we'd love to know what point that is! Appreciate the videos🤘
What about twin DNA GT 45s on a 5.3 LS? What do you think the response rate to back pressure ratio would be? The mindset here is that everything is better with twins ;). Not to mention power to costs.
twin GT45s can do 1300-1400 hp
Would the ebay turbo be limited to 700hp if put on a na 700hp engine?
IT WILL DO A LITTLE MORE
Sounds like a recipe for big gains at low rpm and marginal up top.
@@stlchucko exactly what I would be looking for. More low end grunt
Will have tremendous backpressure, will not be controllable by a wastegate, and will blow out lots of gaskets
@@chipcurrey653couldn't you use a pressure sensor and exhaust bypass to keep the back pressure in check.
Hey Richard just curious what the N/A exhaust back pressure would be before the turbo went on?
Close to zero
we didn't measure but almost nothing
I bought a smaller turbo s300 66mm .91 a/r supposed to but good up to 800hp. 750hp being the higher end of my goals.(gonna start with 500ish hp until I get a 4l80) I have a 6.0 lq9. I bought a 76mm because I was afraid the 66mm would be too small. Do you have a video on turbos that are too small for an engine and what's at stake? And what kinda changes are made with the tune when changing different size turbos?
The rings are gapped just need to weld up an oil return on the oil pan and I can get it back in the truck. Trying to figure what to expect when it comes time to tune.
don't think S300 is right for the 6.0l (doubt it will do 800 hp)
@@richardholdener1727 I think it's supposed to be a replacement for a 6.0L diesel 🤷♂️
@@richardholdener1727 I wasn't planning on doing 800hp with it but that's what it says it's rated for
So a gt45 is good for a 4.8 at 10 lbs of boost for a daily driver
Be sure to like, share, subscribe, ring the bell. Do all that stuff!
Yeehaw
I have one for you which is better a bigger cam or a bigger rocker ratio like 1 to 1.8 instead of the factory one ?
the cam if it also adds duration
@@richardholdener1727 I know if you put to much cam the engine run rough but if you put bigger rocker ratio will te engines run smother for the same lift?
I'm building a 451 mopar and I have a s475. is that going to be big enough ?
FOR NEAR 1000 HP YES-BUT YOU WILL HAVE BACK PRESSURE (HOPE IT'S A T6)
Let’s say both these turbos at 15lbs will the bigger turbo have cooler boost temperatures
they both won't support 15 psi on the motor as shown (the flow rate is the difference)
Dude, I like your videos as they are very informative. But, please when you are talking about a subject with pictures, stay on the pictures so we can get a better look. You flash pics and go back to you talking. You're not ugly but the content, not you talking and only flashes of content. Hope I said it nice enough, not trying to upset you.
Heh, I was just arguing this on boosted lsx today...
GOOD LUCK OVER THERE
👍💪
I'm getting so many mixed reviews, anyone on here know how much boost I can run on a 10:1 static 7.75ish:1 dynamic? PUMP 92 ONLY.
Some people say 12lbs some say 5. It's a turbo car.
dynamic compression does not tell you how much boost you can run
@@richardholdener1727 Thank you very much, the LS forums are all over the place with their answers. I was just trying to give as much info as possible. Going to try to run 10psi on my s480, I know that's baby boost for the s480 but I made a mistake.. lol
@@KreatorOfDeath1985 I made a mistake when buying my turbo too.I bought a s475 when I thought I was getting a s480. It's still in the box, my project has stalled for a minute.
First view!
Posted 11 seconds ago!
Good luck convincing the street weenies around here that they can have too big of a turbo on their Honda's.
What happened rich I thought you were the fly girl on your channel you don't dance no mo
Personally I blame squirrels
As you should
Damn tree rats lol
First