Dyno Results Stock 2008 SRT-10 Convert

[Sho off]

Finally got my baseline Dyno done before my full belanger kit and Mopar ECU goes on the car in a few weeks.

Dyno test was done on a Superflow AutoDyn, which from what I read should be putting out SAE corrected numbers and corrects for atmospheric conditions as well.

Results were:

Hot engine no cooldown. Humidity was 41 % and Temperature was 25 C (77 F).

Corrected numbers:

501 rwhp @ 6072 rpm
471 rwtq @ 5258 rpm

STP corrected Flywheel numbers:

609.8 HP @ 6072 rpm
571.2 TQ @ 5258 rpm


I will post once my mods are on and I get the car dyno'd again in a few weeks.

 

[redrichard]

Great numbers, will be looking for your next post.

 

[redtanrt10]

The bellangers and the ECU will give you 40-50 RWHP that you'll really feel. With the ECU, try and get your octane level up to 95 when you go back to the dyno.

 

[Sho off]

I am running 94 in the car already, so hopefully that will do. I was expecting 40-50 from the exhaust and figured another 10-15 from the ECU?

So is 40-50 a more realistic expectation? The Belanger kit claims 40-50 itself without the ECU from their documentation.

 

[Sho off]

Finally got time to get back to the dyno after I put on my mods. Baseline results are in my first post.

Mods added since baseline are:

Full Belanger kit, hi flow cats.
Mopar PCM
New spark plugs (stock plug model)
AB Wires
Running 94 Octane

Results were:

Hot engine no cooldown. Humidity was 50 % and Temperature was 23 C (73 F).

Corrected numbers:

558 rwhp @ 5862 rpm
529 rwtq @ 5244 rpm

STP corrected Flywheel numbers:

675 HP @ 5862 rpm
639 TQ @ 5244 rpm

 

[fqberful]

Really interesting .. That dyno calculated an 18% driveline loss which is pretty close to the assumed 17% rule of thumb. Did they do a reverse pull or was that just a calculation based on some static constant entered into the system ?

Good numbers BTW, congrats !

 

[Sho off]

Operator told me he used a 15 % drivetrain loss factor, and then the dyno further corrects for temp, air quality, etc.

No reverse pull was done.

 

[SkyBob]

Operator told me he used a 15 % drivetrain loss factor, and then the dyno further corrects for temp, air quality, etc.

No reverse pull was done.

So it's a wild ass guess? Does anybody know what the driveline loss of any car is? Have manufacturers said anything?

 

[fqberful]

So it's a wild ass guess? Does anybody know what the driveline loss of any car is? Have manufacturers said anything?

If you have a dyno that's capable of a reverse pull then yes, a dyno can make an actual determination. The rule of thumb and really close most all the time is for rear wheel drive cars 17% for manual and 22% for slush box. +- 2% ... Every one I've ever done was within those specs.

 

[SkyBob]

If you have a dyno that's capable of a reverse pull then yes, a dyno can make an actual determination. The rule of thumb and really close most all the time is for rear wheel drive cars 17% for manual and 22% for slush box. +- 2% ... Every one I've ever done was within those specs.

Thanks. I didn't know that.

 

[Martin]

There's actually quite a bit of 'cheap' horsepower to be gotten from improving the efficiency of the drivetrain. Small changes like tranny oil, gear oil, and tire pressure can yield a couple percentage points of drivetrain efficiency improvement.

In general, for a manual car with gears and drivetrain as hefty as the Viper, 15-17% loss is about the norm for 'average' setup. If you go to an ultra slick trans and gear oil, go with best possible bearing grease, make sure the brakes aren't dragging AT ALL, and run as high a tire pressure as is practical (without screwing up traction/handling), you can get your drivetrain loss down to the 12-15% range. This shows up as pure RWHP improvements, and the added benefit is better fuel mileage (not that most of us give a cr@p about that...).