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Discussion Starter · #1 ·
Hello! I took my car for a dyno run a few days ago.....slightly dissapointed with the results tho :cry:

Its a genuine 2000 9-3 HOT Aero.....here are the results!

Suppose to have 205 bhp at the fly I believe? I could understand if mine was slightly down (lets say 190?) but not the 173 bhp it achieved at 5000/rpm

Torque was 207 at 4200/rpm

Manifold Gauge Pressure was 0.73 at 4000/rpm

Air/Fuel Ratio was at 14.2 till 3400/rpm then dropped to 11.5 at 4200/rpm and just couldnt keep a stright line untill the red line.

Now im no expert when it comes to cars. I know dynos are not the most reliable of things and cars can over time lose a little bhp (especially at 120,000 miles) but it does seem a little steep??

Its running as smooth as silk *touch wood* but I would just like to know really if theres anything obviously wrong with the reading or if its what I should have expected?

I checked all the sparks,filters ect which seem ok. I was told that resetting the ecu may help but I didnt want to do this untill ruling out a mechanical fault first.

Any other known culprits?

Cheers!
 

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What we need here are other similar figures from the same HP engine to compare to.
205 may be a Madison Avenue advertised figure, Saab should not use these, nor lower themselves.....but...;):confused:
 

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Discussion Starter · #6 ·
So you pulled the transmission and measured the horse power directly at the flywheel? How did you do that?... Ron
Ahh sorry I think i made a mistake there! I thought you meant the flywheel vs bhp at the wheels.

As apprently the HOT aero had 205 at the flywheel which would be about 170 at the wheels (rough guess) only mine is 170 at the flywheel according to the dyno printout! Or have I gone completely insane and talking **** :lol:
 

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The dyno would measure at the wheels, it would not know what power is at the flywheel, it could only guess
 

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. . . bhp at the wheels. . .
This is a non sequitur. BHP stands for brake horsepower, where the brake refers to a friction brake used to place resistance against the flywheel. Thus, the term brake horsepower, or bhp for short, is always a measure of horsepower at the crank or flywheel. Your dyno measured the hp at the driven wheels (aka whp) which necessarily was a lower number since you had approx. 13-15% power transmission loss via the gearbox, halfshafts and cv joints.
 

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Discussion Starter · #9 ·
This is a non sequitur. BHP stands for brake horsepower, where the brake refers to a friction brake used to place resistance against the flywheel. Thus, the term brake horsepower, or bhp for short, is always a measure of horsepower at the crank or flywheel. Your dyno measured the hp at the driven wheels (aka whp) which necessarily was a lower number since you had approx. 13-15% power transmission loss via the gearbox, halfshafts and cv joints.
I see,checking it again it does indeed say Hp at the flywheel. I'll be totally honest I am completely lost if my cars performing as it should. It feels pretty quick but not as other people have described the Hot Aero! Thankyou for the replys tho!
 

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So does it say 173 whp or 173bhp at the flywheel? If it says at the fly wheel that is just an estimate but there should be a reading for Wheel horsepower (Whp)
 
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