I made 219whp on a Mustang Dyno with all the breathing and exhaust mods . It made 319whp out of the box , running real rich . We tuned it up some and made 348whp on my 03 AT5 G35 .

At 6 or 7 psi , your short of the 7 to 8 psi it should be making . Your A/F is very rich . You can see the dip in power where the R4 software pulls a bunch of timing out all at once .

Look for boost leaks around the plenum if you have added a spacer or new plenum . This is hard to do because some leaks dont show up till your in boost and rpms are high . Your serp belts needs to be pretty dam tight so it doesnt slip in the upper rpm range . Have a good tuner that knows the R4 software tune the car . Its a simple tuner program , but has some tricks when up loading a tune the first time . Call Split Second if your tuner gets in a bind after loading a tune the first time .

 

You don't need new injectors, fuel pump, Engine Management, etc. On the stock pulley, the parts that are included with the kit are more than fine and reliable. All you need is a good tune. Out of the box, the EM is tuned to be super rich to pass CARB. Also, checking for leaks is also a good idea. Make sure all bolts are nice and tight.

 

On a 03 AT5 car . The stock kit is good for even the 3.12 pulley and I think you could get away with putting on the 2.87 .

The tune is super rich to be safe I believe....not to pass CARB

 

f/i without a separate piggyback like utec/fcon is a waste.

 

funny, sunday at the track I whooped a s/c 350z every single time.... I guess maybe his problem was the tune or he really couldnt drive... his best 1/8th was a 9.2 at 81mph....stock 350z beats that.... makes me think s/c waste all around

 

A car is only as good as the driver. If the car is fast but the driver cant drive, expect slow times.

 

All driver right there. Especially if it was a stillen sc since we know that those are definitely a waste of time . I guarantee that there are no n/a z's or g's that will even be able to read my plates at the end of the 1/4 mile . Then again, I have a Vortech.

 

Im not sure what headers, but they look orright - definately not stock headers. I believe it has the 5/16" Spacer - It was all done to the car before I got it. Its not a bad idea about checking for boost leaks etc as I could imagine it may cause issues... The power certainly doesnt drop off... its just dull!

I might pull the spacer off and see how it goes from there..

JK

 

The AFR wasnt logged but a guy assisting with the dyno run had the Sensor and a reader and said that was the AFR during the power run. I should get that in a print out next time! The FMU is the standard one issued with the Vortech Kit.

I will perhaps look at testing base pressure but It must be alot for that AFR!

JK

 

I dont think fueling is an issue right now! I have plenty of it!

Im looking at a Stillen oil cooler soon, but im taking the car to nissan soon to get the gearbox fluid done so I will most likely get a tranny cooler put on the day before.

JK

 

Nup brand new from Performance Factory!

JK

 

With an A/F ratio around ~9-10 (aka pig rich... watch out, u might washout your o rings in your injectors) your HP arent going to be great. Find a good tuner that knows how to use the ss blackbox and u can ezly gain +10-20 more hp. Or upgrade to the 3.12 pulley to get 9psi and retune everything at once to save some $$$.

 

Yeah i think I will go for the more boost option.

Not many people have a SS box here in Australia - so it'll be a learning curve for all of us!

JK

 

+1....You need an engine management and a good tune, and I suggested injectors and fuel pump because it's much better to have them, especially after the tune. You got plenty of fuel because you're running to rich, a tune with a type of engine management should fix that

I was running to rich after I got my procharger installed, when the 550cc were in there the car barely started and was bogging, barely staying alive, fouled my sparkplugs, it was way too rich. Got it tuned with a Utec, now running good.

 

You have other issues to deal with 1st before you start upping the boost. Like has been mentioned, you need to get your A/f under control. You are losing tons of power there. Once you get that straightened out, then mess with new pulleys.