I thought I would share some results with you from a local car over here (Australia), to date I must say this is the best performing plenum I have witnessed with power and response.
The build thread is on here: http://nissansilvia.com/forums/index.ph ... 707&st=120
But to keep things on Nico, I’ll continue below...
It is made by Plazmaman Racing (Australia) for the S14/S15 hump back engines only. Base is a CNC bolt on job that mates to the standard lower runners, with a sheet alloy dome.
They have optional velocity stacks inside, which is the one that has been tested. They have an optional 60, 66, or 72mm throttle body. I have nudged 1000 engine hp on my SR20VE with a 72mm on 44psi, so don’t really see any need to go much bigger.
The test car is an S13 with a built with forged S15 engine, 256 degree cams, Precision 5558 turbo on E85 and 25psi. ECU is a Vipec (made in NZ), tested on a Dyno Dynamics dyno, Z32 5 speed gearbox.
First up a base run was done, on 25psi, then the plenum was fitted, run up again without any touches to the tune (fuel or timing).
It shows a 5.2hp peak gain, nothing to get excited about, but if you look at the gap throughout the meat of the power band there are points of between a 20-26hp gain.
Another thing to consider is that the boost level is up to 0.7 psi higher with the Plazmaman plenum on, this will have some influence on the power, however it is still a solid gain.
Once the back to back comparison was done, the car was tuned to suit, timing and AFR’s, the final result on 25psi was this: 474hp atw
Following that it was turned up to 30psi where it made 516hp atw and taken to the drags.
http://www.youtube.com/watch?feature=pl ... sJ1GJojcx0
http://www.youtube.com/watch?feature=pl ... IUv8JoMBaQ
Inside
