Dyno appointment today - advice?

[hcoles]

I'm planning to get my 89 3.2 dyno'ed today at Thunderhill. Any advice re. what to check or ask about to improve the accuracy of the data? I'm planning to get a SW chip so I want to have the data Steve needs. What HP number should I see? My car has a 964 cam and test pipe that's it. I expect the ambient temp. will be about 55F and RH will be 80-90%, it is raining today.

[Wil Ferch]

That's the point.....don't get numbers that are accurate for *only* today's atmospheric conditions. Most machines can either spit out raw data....or....the data can be presented as an SAE-hp "corrected" form...to some baseline atmospheric condition, I think it's 70 degF, 55%RH, and sea-level atmospheric pressure, ~ 14.7 psia. Printout done this way usually shows a "CF" on the footer or header with a number, like 0.9 or somesuch, showing the correction factor applied.

If the dyno operators are worth their salt....they'll know what you are asking and maybe even give you print-out both ways.

Understand also that comparisons to "other guys" are difficult, if not impossible, due the different brand-names and styles of dyno's out there. It is valid, however, if you use the same dyno, make changes to your car, and always ask for "Corrected" read-outs to the same set of standard conditions as you do repeat runs. You'll know whether ot not you are going in the right direction with changes made.....

Get a mongo shop fan over your engine compartment during the run,....and make sure car is tied down well.

What's the dyno?....inertial style?.... DynoJet 248C?.....

[hcoles]

Wil,
Thanks, I'll see if I can get both the raw data and corrected data. Good tip on getting a big fan setup over the engine.
-Henry