04-11-2012, 09:32 AM
IMHO don't get too hung up on keeping the lengths short, concentrate more on not changing the diameter of the piping... Going from 1 3/4" up to 3" then back down to 2 inch then up to 3 inch is NOT good for airflow, it reduces gas velocity, increases restriction (i.e. piping pressure will go up, pressure to the actual manifold doesnt change)...
If the entire intercooling system was say 35 litres (and that's being very generous) - a Garrett T25 at it's peak flow puts out around 21lb/min = 0.15 kg/s (mass airflow) which when you convert to volumetric flow is around 0.12m^3/s - 35 litres is 0.035m^3/second so that'd take around 0.29 seconds to fill, obviously that's at full flow, but I'm sure you can appreciate my point, that it's not so much the volume, it's the reduction in size that affects things...
Also people really aren't working on air intakes hard enough, IMHO it's actually one of THE most important points of a tuned Turbocharged diesel engine, having the inlet as unrestrictive as possible... People assume that as long as it's the same size of pipe as the compressor inlet, it'll do, it all stems from what we learnt from NA engines where shoving a fat cone filter on doesn't do jack... On a turbo diesel, *improving* the air intake system will help massively...
![[Image: iis36at.jpg]](http://innovative.turboecart.com/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/i/i/iis36at.jpg)
Notice the MASSIVE air intake, our engines NEED this... And keep it cool on the way!!!
If the entire intercooling system was say 35 litres (and that's being very generous) - a Garrett T25 at it's peak flow puts out around 21lb/min = 0.15 kg/s (mass airflow) which when you convert to volumetric flow is around 0.12m^3/s - 35 litres is 0.035m^3/second so that'd take around 0.29 seconds to fill, obviously that's at full flow, but I'm sure you can appreciate my point, that it's not so much the volume, it's the reduction in size that affects things...
Also people really aren't working on air intakes hard enough, IMHO it's actually one of THE most important points of a tuned Turbocharged diesel engine, having the inlet as unrestrictive as possible... People assume that as long as it's the same size of pipe as the compressor inlet, it'll do, it all stems from what we learnt from NA engines where shoving a fat cone filter on doesn't do jack... On a turbo diesel, *improving* the air intake system will help massively...
Notice the MASSIVE air intake, our engines NEED this... And keep it cool on the way!!!
