toddk911

So we want the entire air track to be as wide/big as possible and then flowing to smaller and smaller diameter to the combustion and then the reverse on the way out from header to tail pipe, right? Basically mimicing the stacks at a power plant.

So if that is the case then we want a big mouth MAF and the piping then reducing into the intake and then small diameter/stock headers and down pipe and then getting bigger and bigger diameter out to the tail pipe.

Low pressure in, to high pressure to compression to high pressure to low pressue out.

So 5" MAF to 4" pipe to 3" pipe to turbo to intake to 2" to 2.5" down pipe/crossover to 3" cat pipe to 4" to 5" in and out muffler.

951_RS

Yeah, that is why evoms has an intake with a venturi design and gradual decrease in diameter. It's all the rage in the vw/audi world and newer porsches.

http://www.evoms.com/marketplace/vie...-731C5B329E41}

944CS

No, you don't want the intake to be too big, or you'll slow the velocity down. Also on the intake side after the compressor, the larger you make the volume, the harder it is to pressurize that volume. Just make sure you have a nice gradual transition leading into the compressor housing, something around 7 degrees would work well.

If you take a look at the stock J-boot you will see that the diameter reduces very smoothly from one end to the other