It is largely my fault.

I had a baseline dyno done today on a Dynapack. The shop is primarily a Honda hang out but they are close.

The numbers were way too high. I think I finally figured out the problem. They input the gear ratio as 4.497. I'm not exactly sure how this works but I believe the final drive ratio for the Z is 3.538. The pulls were done in 4th gear and I have no idea what the drive ratio is for 4th or even how to calculate it.

- I should have gone in knowing this information. I didn't.
- I should have immediately spotted that the numbers were ridiculously high and had them recalculate it.

Unfortunately, I'm generally ignorant when it comes to dyno's and particularly Dynapacks.

So my questions....

I wanted a baseline to determine changes based on mods. I really don't care about absolute numbers only delta values. If I have them do it again after making some modifications, and rerun the dynos with the same specs, will the differences be realistic even though the absolute numbers are not?

If that isn't the case, then I may see if I can negotiate a cheaper rerun of the baseline since it was partly the fault and I had counted on them knowing what they needed to know. If they had asked me ahead of time to bring in the final drive ratios, I could have done that.

Thoughts? Opinions?

Someone want to buy a stock 06 that puts down 272.9 at the wheels?

 

cool ill trade you my stock 04z with 240hp to the wheels

 

Dyno testing should be done in fourth or fifth gear.

 

Thanks Dave. So does that mean on the Dynapack that they would enter the ratio as 1.00 and then do the pull in 5th?

Dave