707S2K

Well, I've been reading a little on mustang dynos, etc. I've also noticed people saying they get different HP #'s from different DYNO's (some having really low #'s for their setup), my question being, are there any models that are more accurate than others? Whats the most accurate available?

devs2k

it's hard to say what is most accurate

for example, all else being equal, a dynapack dyno which reads at the hubs will read higher than a dynojet..however, the calcuated drivetrain loss % to back into crank hp is a lower % than it is for a dynojet, since the dynojet also has loss due to rolling resistance

theoretically, they'd back out to the same crank hp if calibrated correctly

what you really need to focus on is relative measurements.. for example, if your stock car made 200whp on that dyno and now you have 400whp, you gained 200whp.. if you went to a different dyno and made 350whp, but a stock car makes 150whp on that dyno, then the "delta", or change/ gain is still the same.. in a sense, the absolute number doesn't matter that much

you will often hear people say dynojet or a roller-type dyno is most accurate.. this is mostly due to the fact that it is one of the more widely-used dyno machines and therefore it is something people are more familiar with

a lot of people get bent out of shape when they have a low # or when someone posts a really high #.. at the end of the day, you are really looking for the delta

Kirpich

Also, I heard somewhere, that if the dyno's HP vs TQ graphs don't intercept at 5420 RPM, then the correction factor is off, and the peak numbers are off. Or is it 5250 RPM?

Mark K.

9kFever

5252 I believe. Dynapack is probably the most consistent. I was talking with Mase during our tuning session and he was telling me that without chaging anything other than the way he straps down a Supra he can make the numbers change anywhere from 50-80whp. Therefore, to be consistent his shop now measures for each car to make consistent numbers.

Kirpich

Yeah, I'm getting ready to turbo, got the kit all put together, and I'll go to the tuner and make a couple of baseruns just to see where I'm at now, N/A, 2mm Cometic HG, and cold air.

Spec_Ops2087

5252...and they will only intersect there if the scales of horsepower and torque are the same on the chart.

Who ever told you that doesn't have a clue

TelosHedge

that 2mm HG on an N/A motor will likely yield lower than stock numbers.... just be wary of that

Kirpich

Exactly, it doesn't feel as crisp on takeoff, when getting on the throttle, etc. But overall, there isn't much difference.