Ok call me lazy just do not find the time to open old files to see what happens in this exp.

If I dyno a car and compare 2 setups to see the difference and their is a 100hp difference while in rpm mode, do you see that same difference in mph mode?

so test 1 pull a car with a 100 shot then a 200shot.

look at both pulls together in rpm then mph, do you see the same difference.?

Ricky

 

pretty sure the curves are the same going by memory. Its because RPM and MPH are both a linear axis on the graph. RPM and MPH are both measured, along with HP. The only thing calculated on a Dynojet is torque.

 

Interesting question...first time my car was dyno'd there was some sort of issue with RPM mode on their dyno-jet...all of my runs are in MPH...i have the dyno-jet evaluation software and when I try to switch to RPM it shows odd values...so I have been assuming (watch out) that the differences would parallel each other? In other words I don't know, but I want to.

 

I just checked with some of my files, and they are in fact the same exact curves.

 

yes...same curve

 

hp is calculated not torque

 

HP is Calculated From Torque

Curves should look the same. BTW there are HUGE diferances from the old Winpep programs to the new WinPep 7. Mainly in the TQ curves and they also show up in the HP as well

Example. My car dyno'd 406hp and 422tq with the old Winpep 6. When evaluated with the new Winpep 7 the same graph read 412hp and 390tq. The reason is new winpep 7 seems to calculate the Torque conveter spikes out better

I Always look for a problem when I have big spikes in a graph. some thing is not right and things could get hurt.

Later!

 

Thats not how Dynojets work. They "measure" HP based on drum rotation. Yes, it is "calculated" HP, but that is how they measure HP. The torque is an output only, and is calculated directly from HP and RPM. This is why you can leave off the RPM sensing lead and still see HP, but no Torque. You can't get torque output on a Dynojet without the RPM lead hooked up, but you can get HP from the rollers.

So, the Dynojet "measures" HP, and uses RPM and HP to plot the torque relationship.

 

cool thanks guys.
Ricky

 

They are different actually depending on what kind of setup you have.

I can show you a dyno graph if Mike over at G-Force wants to take a screen shot where my dyno on RPM mode actually makes almost an S LOL!!! On nitrous my car spikes the RPMs really well. If you view by mph mode It was perfect.

On my buddy Chris E.'s (the one from MTI) it is a tiny bit different in RPM vs MPH because of tire spin, but I do know this his single NX Nozzle makes 780rwtq (like 778 or 779) and I think right at like 650rwhp. On a stock bottem end Heads/Cam car

 

A Dynojet measures the amount of time it takes for a car to accelerate the rollers, and uses that measurement to calculate HP. It then takes the RPM Input Signal and calculates Torque.

An engine dyno puts a load on the engine, and measures the amount of force applied back by the engine. That measuremeant is torque. It then takes your RPM Input Signal and caluclates HP.

Engine dyno's are FAR superior to chassis dyno's.

HP = (TQ x RPM) / 5252