Engine/Transmission (1998.5 - 2002) correction factor? what's the difference between....

[johncameron]

I was analizing the different correction factors available with my last dyno graphs on winpep 7, which is the viewer the dyno shop sent me. I changed the CF and it gives me different results. They used SAE on the printouts they gave me.



If I change the CF , here are the results:



Uncorrected-372HP

SAE -355HP

DIN -369HP

EEC -356HP

STD -367HP

JIS -357HP



The conditions were - 62F, 29. 95in/hg, humidity 14%



Why are there so many different CF's and what are the differences. Which one is right?



Thanks, John

 

[Fishin Guide]

"right" is a subject of debate. The best way to look at dyno numbers is by using one dyno and uncorrected numbers. Of course, we are talking about a tuning tool and not a true HP and TQ rating.



So, use what makes you feel good. Most people use the highest number they have got. But I have never had my truck dynoed and gotten a correction factor.



Dave

 

[DTroy]

ISO (International Standards Organization), worldwide

SAE (Society of Automotive Engineers), USA

ECE (European Community), Europe

JIS (Japanese Institute for Standardization), Japan

DIN (Deutsche Industrie Norm), Germany

STP (also called STD)

EEC test methods for motorcycles

 

[johncameron]

So should I use the highest one or go with the SAE CF? I guess I'd like to be "true" and not just go with the highest #'s.



John

 

[DPike]

John, thanks for setting that dyno up the other day. I had fun even if I didn't put my truck on and it was nice to meet you guys. Maybe next time I can get Dad to come down with his and we will both do it. Nice numbers by the way

 

[johncameron]

I'm sure we will have another D-day in VT! I've actually had people ask me it the dyno #'s were real . My buddy with a camero ran 361HP last time we dynoed together and he just shook his head and said "you're gonna twist something off" His car runs 12. 7 @ 115MPH with street tires :--)! Keep in touch and maybe next year we can get a group thing goin.



John

 

[johncameron]

Here is an uncorrected graph with HP and TQ. I finally figured out how to pot both on at the same time!



John

 

[Evan A. Beck]

Here is an uncorrected graph with HP and TQ. I finally figured out how to pot both on at the same time!



John

Man, all the seismograph crap at the beginning of the run is no good. Might want to tell your dyno guy to learn how to do it! Get it in OD lockup, 1,800 RPM, and then begin the run.



As far as correction factor, we always run uncorrected. This is because of elevation mostly. Air density has a lot to do with HP, more than temperature or humidity does. Also, our shop is at like 100' elevation. If we were at 3500' we'd probably run corrected.