Z06Vette.com - Corvette Z06 Forum

**racingfast** · 10-27-2003, 03:13 AM

There are lots of comments on this topic I know. What is the more precise measurement of true HP? :(
I have a DynoJet run of 405 hp at the wheels and just got a 358 hp run from the Mustang.
This is a good reason to NOT like Fords..

I had a 352hp run with Vortex & borlas only....on a dynojet.

Opinions?

thanks!

Roger Ramjet · 10-30-2003, 03:45 AM

I suspect that you got bit by correction factor anomolies. Get a weather station and do your own correcting of raw data.

Did you see this thread?

Thermodynamics of Dyno Testing

z62jag · 10-30-2003, 03:58 AM

For what its worth - Lou @LG Motorsports told me that he would be removing my Vortex intake when he puts my car on the dyno. He said that the Vortex might actually generate lower results due to picking up hot air from the engine compartment caused by a lack of air flow while on the dyno.

Gman2002Z06 · 10-30-2003, 04:18 AM

Actually...The Mustang Dyno's work slightly different than the Dyno-Jet Dyno's...

Mustang Dyno's apply a load, via eletro-mechanical resistance, then rwhp is calculated based on how your "acceleration/unit of time" of this load occurs...

DynoJet Dyno's simply use a large drum, of know mass, as its rotating resistance...Then rwhp is calculated based on how your "acceleration/unit of time" of the drum occurs...

From what I am told the Mustang dyno gives you a "true" or real world rwhp... i.e. my '00 FRC put down 307 rwhp stock, using 12% drivetrain loss and that is 348 flywheel hp (factory rated 345 hp)...My '02 Z06, on the same Mustang dyno, put down 348 rwhp stock, divide that by 12%, using the same 12% drivetrain loss is 395 fwhp (factory rated at 405 hp)

Dyno Jet Dynos give more of a bragging rights rwhp...

The difference between the two is about 10%...Dyno Jets registering the higher hp readings...

Yours for example...358 rwhp Mustang Dyno vs. 405 rwhp DynoJet...358/405=.884...Pretty close to the 10%...

Last comparison one of the F-body guys posted on LS1.com was the something like the following...338 rwhp Mustang vs. 378 rwhp DynoJet...338/378=.901

On the Mustang dyno that I go to...Stock LS1's in F-body cars dyno in the 280~290 rwhp range...Yet nearly every LS1 F-body that posts rwhp using DynoJet Dynos are in the 310~320 rwhp stock...285/315=0.905

Again...285 rwhp using 12% drivetrain loss gives 324 fwhp, factory rated 320 hp...If you use the DynoJet hp, then you get the following...315 rwhp with 12% drivetrain loss gives 358 fwhp, factory rated 320 hp...So you see, it sound great to think these engines are putting out this kind of power, but it's just not as realistic of a number as you get with the Mustang Dyno...

It really doesn't matter what Dyno you use...Just as long as you keep using the same dyno to check your mods...This will keep variances down to a minimum and tell you truely if any mod is helping or not...

Peace...Gman

**jub jub** · 10-30-2003, 05:36 AM

My first dyno experience was on a dyno jet. My best pull was 336 rwhp corrected. At the fest I dynoed on a mustang and pulled 357 rwhp corected. All I can say is go figure.

I will say the dyno is great for measuring power gains as long as they are made on the same dyno and preferably the same day or under the same type of weather conditions.

**racingfast** · 10-30-2003, 05:53 AM

Thanks for the ideas guys, ...that is some heavy reading Roger.......guess since I have 2 pulls on a dyno jet (before and after major mods) and one on a mustang.... (after mods) the bottom line is I got about a 50hp gain with my head/cam package.. and that is that: whatever the final number is.