- GCC Spec IS-F - 417 HP
- Fuel Used - 95 RON
- Three Runs, with aprox. 10 min cool-down between runs.
- All runs in 6th Gear
-Run 1: 349HP - Run 2: 358HP - Run 3: 367HP
- Best run:
X-axis in Speed km/hr


X-axis in RPM x 1000

 

Good runs!

 

And THEN the MOD BUG HITS haha.

 

Nice runs...

But also know that cool down runs normally attribute to a much higher Rwhp than actual..

Reason being is the engine is not running at normal operating temps, if you keep cooling down the car.

Also, if your Dyno shop has the data saved, have them re-graph your last run 3

You will want to have the data graphed SAE Corrected & Smoothing set to 5

Correction Factor STD numbers with smoothing Set to 0, will also always show much higher numbers as well.

Best Regards,

Joe Z

 

awesome runs! and, let the modding begin...

 

Great numbers, but I would also like to see the SAE 5 graph as well.

 

Question: so if the advertised HP is not really what exists, is it safe to assume the same of other automakers?? I mean, why would Lexus continue stating ~416hp when that is clearly not the case. We have seen several stock dynos on here that back up the OPs data.

 

OEM data is crank HP before driveline loses. Its the same for everyone, nobody is putting to the wheels what the manufacture states off the lot.

 

Right on as clifftrail stated.. The 416 HP is measured at the Engine..

Once you factor in the 16-20% drive train loss, you will get the number of Rwhp..
Which is the power being put down at the Rear Wheels.

Typical stock IS-F's put down approx 330 to 350 Rwhp SAE Corrected on a Dynojet

The OP's dyno graph showing the "367 Rwhp" number - with a Standard correction factor, is very Generous for stock numbers.

Joe Z

 

Cliff and Joe, thanks and...damn it! Definitely good to know!

 

Agree with Joe... if you want to set a baseline a bit more 'consistent' with national averages... Smoothing set to 5 & SAE are going to be necessary.

Nice pulls,
Dave

 

Don't forget that different engine layouts have different drivetrain loss, and sames cars with different transmissions (automatic vs manual, etc...) will have different drivetrain losses.

 

All possibly true, but not the case with the IS F. One engine, one gearbox, one layout - they're all the same.

 

For those of you who want to mod your cars and re-dyno.. please note that drive train loss is not a fixed percentage. It's a fixed number.

If drive train parts remain stock, there is not reason why the loss should be proportional to the power output.

 

Drivetrain loss is neither a fixed percentage nor a fixed number. There are way to many variables present to apply either and be accurate for every circumstance. There are dynos that measure drivetrain losses as the car coasts down to a stop at the end of each run and you will note from these graphs that drivetrain loss is exponential not linear. This is better than just adding on a fixed number but still not totally 100% accurate.

If you're interested here is a very good article about drivetrain loss:

http://www.modified.com/tech/modp-10...oss/index.html