imazman

Past summer drove a friends 5.0 Mustang with an after market super charger and it was raw power. After that I was determined to get an SC for my Z.
So in the fall I bought a Stillen super charger, oil cooler, and PLX boost gauge. Finally finished the install with my mechanic and got some drive time.
The results were not the raw power like the Mustang but I was told that was due to large displacement of american. Anyway, I don't know what I should expect as I don't know what 400 hp in a Z SHOULD feel like.
I last week I put it on the road in 3rd gear and took it up to almost 7k RPM and boost gauge read around 7.4...so I think it would be pretty close to Stillen's 7.8 to 8.4 boost at 7k RPM.
So yesterday I took it to a dyno to get an official HP/Torque measurement. The guy did 1st pull in 4th (albeit 5th is 1:1) with a load of 10%...result was 337 HP / 286.4 Torque and the dash boost gauge only read around 5.8. So he tried different load, tried different gear, etc. Here are the results:
Run 1: Gear=4, Load=10%, HP=337, TQ=286.4, Boost read ~6.3
Run 2: Gear=4, Load=7%, HP=336.9, TQ=284.6, Boost read ~5.8
Run 3: Gear=5, Load=5%, HP=328.8, TQ=273.1, Boost read ~5.5
Run 4: Gear=3, Load=5%, HP=327.1, TQ=274.3, Boost read ~6.1
Dyno guy said something was not right and didn't think the super charger was really spinning up. He mentioned a smoke test.

That night after getting depressed about the dyno, I decided to try it out on the street again in 3rd gear up to 7k...and I read 7.6 on the boost gauge. So twice running on the street it seemed to get pretty close to Stillens boost range, but not on the dyno...and since I don't really know what to expect I don't know what is right and what is wrong.

So today I called Stillen, they said it might have a Boost leak too. I talked to the mechanic and he said if it had a leak you would hear it leaking air and idle wouldn't be correct...but idle is correct and I don't hear any leaks.

I did use cypher to get successful data logs for two of the runs, I also grabbed a data log from my street test that night. i looked through the data but I don't really know what I can look for.

I would appreciate if anyone would like to provide helpful commentary.
Thanks for your help in advance,
/Z/