G3 + Stillen CBE + Berk Cats

Z eliminator

Base line 260.8 to 265.6 Hot engine vs cool engine
Stillen intake 280 to 285.6 (hot engine cool engine)
G 3 + CBE + berk cats 284 to 290.6.

Very disapionting.
On my way to get dynoed i pluged in my Cobb Acess to moniter the A/f and my car ran terrible. Night and day difference from the night before.
On the 284 run the i had the cobb pluged in and the A/f was
13.22 @ 3050 rpm
13.12 @ 3512
12.79 @ 4000
12.79 @ 4500
12.6 @ 5037
12.38 @ 5500
12.57 @ 6062
12.33 @ 6500
12.23 @ 7000
11.96 @ 7137
11.69 @ 7250
11.69 @ 7362
11.66 @ 7487
11.31 @ 7525
11.03 @ 7537
11.00 @ 7562
10.66 @ 7550
10.11 @ 7550

Intake Temp 84.2
water temp 185
Oil temp 172.8 to 176.0
It was a hot and humid night.
Out side temp 87 in dyno room.

I removed the access tuner and let the car cool down.
The next pass was 290.6 rwhp/
Net gain 25 rwhp on a cool engine
Net gain 24 rwhp ona hot engine.
If i would have let it cool down another hour it usually make about 4.5 rwhp.
so it may have made 30rwhp.
The access port must have reset my learning curve on the ecu back to stock.
It gained 5 rwhp by adding the cats and the stillen exhaust !!!!!!
Can not wait to see what the headers will do!!!
It may make another 2 ot 3 rwhp. for a total of 28!!!!!!
After i had the exhaust and cats put on the car was a lot faster, it ran great and i could break the tires free at will. It was very quick, but the dyno numbers are very dissapionting.
Now for the good news. frrom 4000 to to 5000 rpm it made 5 rwhp more.
From 5000 to 7000 rpm more it made 9.5 rwhp.
It showed good gains till 7000 and then it was did very little..It should have made at least 300 rwhp? I belive that the ecu went very rich and robbed the engine of power.
I will drive for a week and then re dyno it with out the cobb hooked up to the car.
The A/f reading were take from the cobb.
pulley and headers are next.
50 to 52 rwhp with the above mods (not in this case)

ssqpolo

give ur ecu some time to adjust i guess. still 30+hp is not bad at all for 3 bolt ons. on 350z, intake added 3-5 hp, exhaust...most 7-10hp. but in stillens ads...52 hp...to the crank

Denny McLain

[QUOTE=Z eliminator;191223]Base line 260.8 to 265.6 Hot engine vs cool engine
Stillen intake 280 to 285.6 (hot engine cool engine)
G 3 + CBE + berk cats 284 to 290.6.

Very disapionting. [QUOTE]

If the horsepower rating is SAE that really is not all that bad and dyno's do vary especially if it is a Mustang dyno. In addition, remember the manufacturers claims are always either absolute best case or manipulated. The last point to not be bummed is your air/fuel if the reading below are even ballpark close indicates there is more on the top end.

Also have the Cobb AccesPort which was purchased after the last dyno session and in comparing it's AFR to the dyno sheets, the readings are off about a half a point low. My next dyno session I'm going to log AFR and to compare to the dyno printout to for a better comparison. No big deal if they are off some, even a dummy like me can add a half a point as long as they do not vary from that half a point.

Lean on the bottom getting rich on the top end appears to be the norm and if you pull some fuel out on the top end you should pick up some. Might even help to add some below 3000 rpm but until there is a reference point on AFR I'd be real carefull and be gentle.

Next time log the timing as mine is pulling out timing as I see a link to water temps. See as much as 4 degrees and it appears to make quite a difference.

Mine picked up 36 rwhp from stock and has headers in addition to your mods. Beware... headers are a chore to do and your $425.00 02 sensors are in danger if you try and remove them from the stock manifolds. IF I were to do it again, I'd leave the 02 sensors in the stock manifolds and just buy new ones for the headers. That way I would be able to return it to stock w/o worrying about the 02's.

Now you got me a little lost. My car picked up 12 hp just from the cats and JIC Y-pipe. You might be right though on the headers.

Seriously doubt you would see more than a 10 hp gain at best from the shorty headers and pulley. Also added the pulley after my last dyno session but the big ticket in my opinion is getting the Cobb tuning software up and working so you can play with the timing.

Denny McLain

The ECU on these cars appears to be a man of mystery and who knows what is really going on or what they will do?

IF the factory hp rating is correct and IF mine is representative of a typical 2009 370Z. My baseline dyno runs computes to a 17% parasitic power loss. IF that is truly representative, you'd see 35 hp crank hp from 30 rwhp.

Z eliminator

I was rading a thread where Forged Performance did a header. cat. stillen exhaust, intake and got 50 to 52 rwhp.
I am dying to find out how they got that # ?????
The car was dynoyed on a dyno jet last night,
Next time i go im going to let the car sit for 2 hours before i dyno it.
Im sure it will go over 300.
I drove it to day and it runs great. No idea why ?
thanks for the incouriging words.
Steve