Tricks to help large cubes with small turbo breathe
#1
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What can be done, beside switching to larger turbo? I have 383ci with 68mm turbo (TC78), and want to help it breathe keeping this turbo.
Would things like a) better intercooler b) larger wastegate help choked engine to produce more power? I read somewhere that guys did put second wastegate to help breathe when they were turbo limited too
Would things like a) better intercooler b) larger wastegate help choked engine to produce more power? I read somewhere that guys did put second wastegate to help breathe when they were turbo limited too
#2
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What can be done, beside switching to larger turbo? I have 383ci with 68mm turbo (TC78), and want to help it breathe keeping this turbo.
Would things like a) better intercooler b) larger wastegate help choked engine to produce more power? I read somewhere that guys did put second wastegate to help breathe when they were turbo limited too
Would things like a) better intercooler b) larger wastegate help choked engine to produce more power? I read somewhere that guys did put second wastegate to help breathe when they were turbo limited too
#5
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The biggest thing you can do with what you have is go conservative on the cam, absolutely no overlap. Also, it may sound crazy, but put the turbo as far away from the engine as you can. With a small cam and long hotside, you'll be effectively reducing the CFM that both the turbine and the compressor need to flow, putting them both in a better efficiency range and you can actually make more power this way, but you'll lose spool time (which won't be a problem with that turbo on a 383 no matter how you slice it).
We actually made more power on a rear mount stroked Windsor than we did when it was mounted right in front of the engine with a coated and wrapped hotside. The exhaust cools before it gets to the turbo, effectively reducing the amount of CFM that is being pushed through the turbine. This typically only helps if your turbine is the main restriction and not your compressor.
The smaller cam will have this benefit for both the turbine and compressor.
Also, run the largest downpipe you can fit.
We actually made more power on a rear mount stroked Windsor than we did when it was mounted right in front of the engine with a coated and wrapped hotside. The exhaust cools before it gets to the turbo, effectively reducing the amount of CFM that is being pushed through the turbine. This typically only helps if your turbine is the main restriction and not your compressor.
The smaller cam will have this benefit for both the turbine and compressor.
Also, run the largest downpipe you can fit.
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#8
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Didn't you get an answer on that...?
https://ls1tech.com/forums/forced-in...es-help-7.html
https://ls1tech.com/forums/forced-in...es-help-7.html
#9
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If your inter cooler has significant pressure drop swapping it out will help a bit. What kind of pressure drop do you have?
#12
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Depending on how much boost you're running, 4psi could be considered huge.
If 40psi, then 4psi is 10%
If you're only running 14psi, then that's 29%. Huge by any standards
If you have a major restriction imposed by the turbo, then clearly you need to optimise everything else. Your IC should have almost zero restriction, and be very efficient at cooling
w/g will make no difference. If your current gate was too small, you would lose control of boost as load increases. You dont mention that happening ?
It would still be worth finding how much pre-turbine pressure there is though so you can find a good balance. Likewise turbo speed would be interesting to know, to determine if you are ringing the life out of it, and again find a sweet spot.
Then with that data try and select a camshaft to work around the inefficiencies.
It would also help determine whether more boost less timing, or less boost more timing is the best way to go ( or spend some time on a dyno )
If 40psi, then 4psi is 10%
If you're only running 14psi, then that's 29%. Huge by any standards
If you have a major restriction imposed by the turbo, then clearly you need to optimise everything else. Your IC should have almost zero restriction, and be very efficient at cooling
w/g will make no difference. If your current gate was too small, you would lose control of boost as load increases. You dont mention that happening ?
It would still be worth finding how much pre-turbine pressure there is though so you can find a good balance. Likewise turbo speed would be interesting to know, to determine if you are ringing the life out of it, and again find a sweet spot.
Then with that data try and select a camshaft to work around the inefficiencies.
It would also help determine whether more boost less timing, or less boost more timing is the best way to go ( or spend some time on a dyno )
#14
9 Second Club
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hence why I also said it would be a good idea to monitor turbo speed, just to see if you are spinning the nuts off it.