Stillen Results...
 

Hey everyone,

We completed the install on our 370z using the Stillen Supercharger kit and 9lb pulley.

The car produced 475hp at the flywheel and 340 ftlb torque.

When we went to tune the car on Tuesday we had issues for a long time trying to balance the voltages at idle and just above idles and when coming off throttle.

We eventually balanced the MAF's by rerouting the pipe work down beside the charge cooler pump in the driver side/left side of the front bumper.

Once we got up and running we found the car to only be producing 7.5psi.

Our setup is as follows:

Stillen SC kit
25 row oil cooler
9lb pulley
MXP Exhaust
Decat/Test Pipes
Custom Tune from TDI North

My theory on the 7.5 psi is the decat/test pipes creating no back pressure. Would anyone tend to agree?

I have CSV file from logs from the day after doing a few pulls but i cant seem to attach it here?

Can anyone chime in and let me know what they think? I would have expected the car to do well over 500hp at the flywheel.

Cheers

Just out of curiosity where are you reading boost from?
The TP should not really cause an issue, most guys run the same setup without boost loss. My first guess would be a leak somewhere, did you ever see the car hitting 9PSI prior to re-routing the pipes?

No the car never hit 9psi at all.

We are measuring boost directly off the inlet manifold.

Would you suggest a smoke test?

I would do a leak test to start, my only other thought I know this was with the rotrex units (GTM kit) but not sure on the vortech units. Need to run the SC for so many "miles" or time to break it in and get it spinning fully.

I'll perform a leak test tomorrow to see if there is a leak anywhere in the system. I know the charger needs the oil dumped at 1000 miles after the break in point.

Any other ideas?

I am unfamiliar with the UK. At what elevation are you guys at? Elevation will affect both power and max boost.

Elevation at mapping was 13m from sea level.

Fuel used was Shell V-Power Nitro 99 ron (equivalent to your 93)

Any help is appreciated.

Boost can be thought of as resistance to airflow, so yes, you might lose boost, but should not lose power, with a freer flowing set up. Are you sure you are down on power or just boost pressure?

How are you testing it at the flywheel?

Careful...your motor is about to blow !!! :eek:

Ask me how I know.

It may be that the supercharger isn't reaching its efficiency range fast enough without some type of baxkpressure. This is definitely a documented issue when running a very free flowing exhaust with centrifugal Superchargers. What does the dynosheet look like and what type of Dyno was used?

pics of your new inlet piping you may have choked the charger

Here is a data log of the car as well.

I assume it is on an engine dyno (i.e. engine is out of the car) rather than a chassis (rolling road) dyno, otherwise there would be a correction factor for drive line losses, or the OP has confused flywheel with "wheel" figures. I guess we'll get feedback in due course.