Josh B

I went over with another couple of Porsche buddies and did a dyno run in the 968 on a dynojet. The motor is stock - no aftermarket chip or airbox mod. 140k on the odometer. About 75 F outside.

Any guesses on the results before I post them? The car came in right where I expected it to.

This place in Marietta is great - they have a special - three pulls for $50 on Thursday evenings.

dougs968

How about 193 at the rear wheels?

Josh B

Close - I've got a scan of the curve and a video of the run I'll post up tomorrow.

BikePilot

I'm going with 200.6 at the wheels (assuming an inertia dyno with standard SAE correction). -~6% from that if it's an eddy current.

MC 968CS

184

pontifex4

42

pontifex4

What was the question?

tamathumper

194, if this is the Price is Right.

Josh B

Some pretty good guesses on here

Josh B

Double post

BikePilot

Very nice! I wonder what it'd take to smooth out that dip from 4.5-5k? One of my bikes had a similar dip and it went away after I did some work tuning the fuel and ignition maps.

odurandina

nice.

that indicates about 250 at the crank, right?

Josh B

Yep - I wonder too - I know there is a lot of room for adjustment on the timing on these cars.

Well - 15% loss of the rated 236 at the crank is 200 on the ground. Usually that is the accepted rule of thumb for drivetrain loss.

car_slave

I bet your valve timing is off.

BikePilot

I wish there were an easy, inexpensive way to play with fuel and ignition maps (I use a dynojet powercomander on my bike and it works quite well). For my bike I started with a base map and just gradually tweaked stuff, tested, tweaked, tested, etc. 'till I wasn't getting anymore improvements. Worked out really well, gained 6mpg, ~12hp, and much improved power curve. That bike had really abysmal mapping from the factory though so improving on stock isn't staying all that much.

FWIW I felt that the throttle response on my car was a little off and it had an odd flat spot in the power about 500rpm lower than that. I put on a new TPS when it was suggested here that the TPS likely wasn't reading properly at WOT, preventing me from checking codes indicated by a sporadic check engine light. The TPS fixed the code-checking thing and also much improved throttle response. It's hard to tell without a dyno, but I think that the flatish spot I felt is much reduced. A week of driving now and no CEL either (the code it threw was knock sensor #2).