i have 997tt 2008 auto trans

with some mods ,, exhaust , valves ,, headers ,, ecu tune

is this normal ??? or something wrong with the tune ???

 

Its going super rich. You can see at the end of the run the AFR dips. Are you sure that there isn't something else going on with the car?

Mitch

 

mm nothin ,,,, maybe somethin wrong with the tune ???

 

Maybe but I wouldn't think so. It is strange for a tune to just go that rich. Most tunes are pretty close in terms of fuel. You AFR's drop all the way to almost off the meter and it is strange it doesn't do it through the whole power band.

Has it always been like this or did it just behaving strange recently?

Mitch

 

i felt strange when i saw the dyno ,,, 437 whp for moded 997tt is strange ...

it was dyno jet ... i thought it will be 470 whp or somethin like that .... feel sad

 

Did you dyno in AWD or RWD? What was your boost pressure? Did they graph boost? Have you done a boost leak test?

The same file you have is being run in Tblountman car on a tip and he did 1/4mile in 11.14sec.

 

thnx dan ... it was 17 psi in the dash ... and no there are no leaks ...

 

RWD or AWD on the dyno?

 

awd dyno

 

I could be wrong... but everything I have heard and having tried it myself, you cannot dyno the Porsche in AWD mode on a DynoJet. When we tried to dyno my car, the rollers would not be spinning at the same RPM causing the EXACT same issue you had. My 800HP car made about 550 awkward horsepower on a DynoJet AWD.

Give me 5 mins and I will upload my dyno to show you.

 

MMM i think thats true ,, the man told that when the rpm reach 5 it became very slowler to reach 6 in the 4th geer ... so i think you are right ..
it could be the dyno problem

 

You can blow up your center diff, so NEVER dyno on that again. You have to dyno on a Mustang Dyno or a Dyno Dynamics. The DynoJet usually reads about 50HP higher then a Mustang. When you dyno in rwd you also have more to show without as much drivetrain loss, you can see that on others performance kits.

Here are my dyno sheets using a DynoJet and you can see the issue too. 1 roller was spinning at about 1000rpm off of the other one whether we were in 3rd or 4th gear. The day before this car made 700+ awhp on my Mustang. Here is the result of the Dynojet.

 

Dan, would a difference in dynos explain the blip in the AFR toward the end?

 

I cant enlarge his dyno sheet to see that.. But thinking outloud, if he his front wheels are moving faster then his rear wheels or vice versa, this could through his PSM thinking the car is having an issue and then adjusting the ECU to compensate what power is being delivered. If it is going rich, then it would try to be giving it more fuel to make sure it is safe... Just thoughts. But at the end of the day, we cant get EXACT readings on AFR or power without properly dynoing the car.

 

here in kuwait we do not have Mustang Dyno or a Dyno Dynamics ...

dan do i need TCU upgrade ???