kahren

the biggest amount of power transfer to the eccentric shaft from the rotor occurs at teh first 1/3 of the power stroke, so dont worry about portign too much down because of that, but you dont want to have it open too early as the low will suffer. basicly any porting you do will hurt low end.

i try to keep the low end as best as i can to that of what comes from factory





the green line is stock s4 motor with stock turbo, 3 inch exahust and big IC

at 9 psi

the red line is a ported motor with a 60-1 t04s at 7 psi untill 4k , but that is good enouf to compare low end we are looking at under 4k rpm anyway.



the blue line is the same ported car but with boost going up.



this is the same exahust port that you see in my sig, which is slightly smaller then the pictures that u see above.

pinkfloyd

wow thats great info. It really helps me understand how it effects the car with thos charts. Im kinda mad though about the green line. I plan on 3in all the way back with 10psi and a big V-mount IC. I wa shooting for 250 at the wheels and the one you show has 239hp.

kahren

well that was at 9 psi so i am sure u can get 250 with 10 psi , given same mods timign was also retarded from stock on that just to keep it on teh safe side.

pinkfloyd

Where you using stock injectors and stock ecu? I will be using the rtec 1.5 and I feel that will allow me boost safely to 10psi. I will also be using my friends wideband to make sure I don’t run to lean. I know this will be pushing the stock fuel injectors, but I do have an fd fuel pump which should help me a little.

kahren

u cant do that with stock stuff, you will start to lean out in the midrange, and the afc cant correct that, not sure what you have.



at the time there were secondary 950 cc incjtors, afc, fcd stock ecu 9 psi

racign beat turbo back.



we had the car at 220 at the wheels before the big IC and it started to lean out in the midrange so with the intercooler the 950cc went in.

pinkfloyd

How much was your timeing off. mine will be retarded 2 deg. at 10psi

kahren

i think at the time it was retarded by 2 degrees.