Are you telling me the total pressure drop between turbo outlet and inlet manifold is only 0.1bar (1.45psi) ?
Is that a measured value, or guesstimated one - with the RS2 intercooler and usual crossover pipe nonsense ?
If that bad a setup is less than 1.5psi then I'm surprised and delighted - I could now percieve a 1psi pressure drop with the AAN or MTM-like intake manifold with a more efficient intercooler much easier than I first thought.
I know that all this calculation and theory is useless without real world experience, but it is vital in my opinion to do these calculations before investing thousands of pounds, dollars or euros into a monster engine build. The maths is only as good as any assumptions that are made along the way.
Having lots of instrumentation for pressure drop and air temps is the only way to measure performance of intercoolers - so there is always some guesswork until readings can be taken off the engine.
The VE parameter hurts my head, because I don't know how to measure that, and I'll bet its not a fixed paramater across the rev range... You quickly see that maximum VE is desireable in the low-mid range so that the turbo can sustain higher boost values without surging.
I guess my goal is now distilling to one of an engine capable of 500bhp on the redline but with 500Nm of torque available as early as possible. All of which gets me wondering if I could stay with stock rods - in the knowledge of that torque target and the generally accepted view that stock rods are good for 550Nm. However, a nice set of forged race-spec items are a mighty good insurance policy.
My next challenge is working out what fuel needs I have - that is easy enough. The harder thing for me is to estimate what CR is needed. I really want to keep it as high as possible so that driveablity off-boost is not further reduced.
The RS2 turbo is hard to beat for day-day driving with rod-bending potential of ~550Nm available in the mid range, but a maximum power of 360-380bhp is its only real downfall. All of those on stock CR and bottom-end.
Its clear why your K26/27/29 hybrid has great potential with strong torque in the mid-range and capability for 450bhp at the redline. Do you have any compressor maps for that turbo yet ?
Ahh hell - sorry for such a long post everyone !!!!!
Paul
Is that a measured value, or guesstimated one - with the RS2 intercooler and usual crossover pipe nonsense ?
If that bad a setup is less than 1.5psi then I'm surprised and delighted - I could now percieve a 1psi pressure drop with the AAN or MTM-like intake manifold with a more efficient intercooler much easier than I first thought.
I know that all this calculation and theory is useless without real world experience, but it is vital in my opinion to do these calculations before investing thousands of pounds, dollars or euros into a monster engine build. The maths is only as good as any assumptions that are made along the way.
Having lots of instrumentation for pressure drop and air temps is the only way to measure performance of intercoolers - so there is always some guesswork until readings can be taken off the engine.
The VE parameter hurts my head, because I don't know how to measure that, and I'll bet its not a fixed paramater across the rev range... You quickly see that maximum VE is desireable in the low-mid range so that the turbo can sustain higher boost values without surging.
I guess my goal is now distilling to one of an engine capable of 500bhp on the redline but with 500Nm of torque available as early as possible. All of which gets me wondering if I could stay with stock rods - in the knowledge of that torque target and the generally accepted view that stock rods are good for 550Nm. However, a nice set of forged race-spec items are a mighty good insurance policy.
My next challenge is working out what fuel needs I have - that is easy enough. The harder thing for me is to estimate what CR is needed. I really want to keep it as high as possible so that driveablity off-boost is not further reduced.
The RS2 turbo is hard to beat for day-day driving with rod-bending potential of ~550Nm available in the mid range, but a maximum power of 360-380bhp is its only real downfall. All of those on stock CR and bottom-end.
Its clear why your K26/27/29 hybrid has great potential with strong torque in the mid-range and capability for 450bhp at the redline. Do you have any compressor maps for that turbo yet ?
Ahh hell - sorry for such a long post everyone !!!!!
Paul
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