Sequential turbo set-up
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Sequential turbo set-up
Has anyone here ever done one on an LS motor? Thinking of going turbo in the near future and saw how the Gen III RX7 had the sequential turbo set-up to help low and high end power. Figured it looks like a good idea for a street friendly car you and really boost up at the track. I tried the search and didn't see anything.
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Not really. Bigger displacement helps with low end torque. What I'm saying is it eliminates the turbo lag a larger turbo experiences. It seems like a good idea and wanted to see if anyone has tried this before on an LS motor.
#4
Best way to minimies lag is to pick the correct turbo(s) for the job. What are you trying to do with the car? Drag? Road race? Street?
Drag, you can always use a little two step or tran break (if Auto) to help.
Road Race, Simplely make sure you are in the right gear for the corner.
Street, dont worry too much as you will blow the tires out anyway.
Chris.
Drag, you can always use a little two step or tran break (if Auto) to help.
Road Race, Simplely make sure you are in the right gear for the corner.
Street, dont worry too much as you will blow the tires out anyway.
Chris.
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It is only practical on smaller engines like the rx7 rotary and 2jz in the Supra. Coming from the import world myself I can tell you most did away with it on Supras especially by converting them to run in parallel by rigging the waste gates. It made more topend power this way.
And it obviously wasn't popular as most changed to big single turbos anyway. It only made sense in the OEM world when it came to marketing the cars as most buyers associated turbos with lag.
And it obviously wasn't popular as most changed to big single turbos anyway. It only made sense in the OEM world when it came to marketing the cars as most buyers associated turbos with lag.
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#9
I've looked into this a ton an am thinking about doing on on a fbody but purely for the wow factor. Compound boost setups really are more geared towards smaller high rpm motors. On Ls motors a properly set up turbo will make all the same power then a compound set up. Also in some cases low rpm boost is not a good thing.
The theory behind it though I find mesmerizing! Exhaust to first turbo with a wastegate set to 8psi dumped back into the down pipe merged to the secondary turbo with an additional wastegate to regulate boost. The intake track is equally impressive! The small turbo draws charge air via large turbo...cool stuff!
The theory behind it though I find mesmerizing! Exhaust to first turbo with a wastegate set to 8psi dumped back into the down pipe merged to the secondary turbo with an additional wastegate to regulate boost. The intake track is equally impressive! The small turbo draws charge air via large turbo...cool stuff!
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It is only practical on smaller engines like the rx7 rotary and 2jz in the Supra. Coming from the import world myself I can tell you most did away with it on Supras especially by converting them to run in parallel by rigging the waste gates. It made more topend power this way.
And it obviously wasn't popular as most changed to big single turbos anyway. It only made sense in the OEM world when it came to marketing the cars as most buyers associated turbos with lag.
And it obviously wasn't popular as most changed to big single turbos anyway. It only made sense in the OEM world when it came to marketing the cars as most buyers associated turbos with lag.
I've looked into this a ton an am thinking about doing on on a fbody but purely for the wow factor. Compound boost setups really are more geared towards smaller high rpm motors. On Ls motors a properly set up turbo will make all the same power then a compound set up. Also in some cases low rpm boost is not a good thing.
The theory behind it though I find mesmerizing! Exhaust to first turbo with a wastegate set to 8psi dumped back into the down pipe merged to the secondary turbo with an additional wastegate to regulate boost. The intake track is equally impressive! The small turbo draws charge air via large turbo...cool stuff!
The theory behind it though I find mesmerizing! Exhaust to first turbo with a wastegate set to 8psi dumped back into the down pipe merged to the secondary turbo with an additional wastegate to regulate boost. The intake track is equally impressive! The small turbo draws charge air via large turbo...cool stuff!
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There is a guy on performancetrucks right now, Vicalma, who is doing a compund setup on his 90 Chevy with a 4.8. Kyle at KBracing built the kit. I think he is in the process of getting it finished up and seeing how it goes.
There have been a couple guys try the compound thing with a magnacharger and turbo but they couldnt control the boost
There have been a couple guys try the compound thing with a magnacharger and turbo but they couldnt control the boost
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2 wastegates and bov's? Did he run each turbo off each manifold? I would see where running off the motor and exhaust would be better for spinning a large turbo. Just wondering how they did their set-up.
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Compound boost is only really useful when the pressure ratio capability of a single turbo is not sufficient. On gas engines we don't often have that problem though, because most turbos would easily hit 40+ pounds on a gas engine if they were allowed to in a free-floating setup. Sequential boost however is a different thing entirely. I built a sequential boost setup several years ago with a roots blower and a turbo and it worked very well. Not cost-efficient though.
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Compound boost is only really useful when the pressure ratio capability of a single turbo is not sufficient. On gas engines we don't often have that problem though, because most turbos would easily hit 40+ pounds on a gas engine if they were allowed to in a free-floating setup. Sequential boost however is a different thing entirely. I built a sequential boost setup several years ago with a roots blower and a turbo and it worked very well. Not cost-efficient though.
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Have you considered a centrifugal supercharger? Take a NA motor that makes good power, toss on a centri blower, and you'll add linear power all the way to redline. As cool as it may be to have an instant 10, 15 psi or whatever, on the street, it's not beneficial because traction is also linear as the speed increases, so your power should also increase as your speed/rpm increases. It's a cool feeling to have your tires right at the edge of losing traction through the entire rpm range, which is what a centri blower gives you thanks to a linear boost curve.
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The best advise i can give is don't do a compound setup. They are a giant waste of time, money and add unnecessary weight to the car on top of that they will give you more issues then they're worth especially if not done correctly. If you choose the right turbo(s) from the get go you shouldn't have any issues spooling them. And Marc, the guy in the video went back to a single precision 67 because of the issues that he had with the compound setup.