"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..."
Originally Posted by Steve1969LS1
WS6 = IN YOUR FACE
SS = Classic subtle muscle
I like the back have of the SS more and but nothing beats the front end of a WS6..
There's several factors in dyno's which is why everybody says it's nothing but a number to tune by. Even dynojet's have different versions of dynos. On top of that, there's a variance if they're corrected or not, or how they're 'corrected'.
Add in the difference in drive train loss between cars and you can see how much variance there is.
My point is this. You put a car on a dyno to help you dial it in. It doesn't really matter what number your car makes (provided it's dialed in correctly) because it'll still run the same regardless what another dyno says. The idea is to get it dialed in.