Hmmm, I'm agree with you guys on the BS system, I'd like a legitimate dyno run, from factory, to new exhaust, as most other exhaust companies do this for you, why can't he? It just seems fishy to me, but what I want to know, is how accurate are dyno's for AWD, sorry to throw the topic off subject

Hmmm, I'm agree with you guys on the BS system, I'd like a legitimate dyno run, from factory, to new exhaust, as most other exhaust companies do this for you, why can't he? It just seems fishy to me, but what I want to know, is how accurate are dyno's for AWD, sorry to throw the topic off subject

About as accurate as for any other drive system. I've done quite a bit of reading on dyno testing. There are different amounts of drive train loss between manual and automatics, 2wd whether is front or rear wheel drive, and 4wd drivetrains. Usually you can calculate pretty closely what the engine HP is using some standard percentages and based on other peoples experience.

Engine HP, and really even peak WHP, is not whats most important though. Even how close to accurate they are to the actual HP is not that important, because numbers can differ from one dyno brand to another, and even between shops depending on correction factors used and how the operator sets up the dyno and runs the car.

The MOST important thing, is the improvements made during tuning... you want consistency and repeatability. Almost every article I've read has said the best thing to do is, if you start with one type of dyno at a shop with a certain operator, stick with the same one throughout the process. IE find a shop that you like and trust, then only use them when you start making mods and tuning and going back for more testing. That way you know any differences are the result of the changes you made and not from switching dynos.

I completely agree with what you said, and I agree with dyno's should primarily be used for consistent tuning!