I have a Comptech header, exhaust and drop-in filter installed on the car. I also have a Comptech test pipe ready to be installed. (I'll put on the SC in a year or so). My question is this - does it make sense from a curiosity or technical standpoint to do a before and after dyno on the same day that I have the test pipe installed? The reason I'm asking this is that I've read that the ECU won't have time to adjust to the new set up and a before and after dyno would therefore be useless. Would it make sense to do a dyno after the install to check the A/F?

 

Dyno is really more for your own personal gain. You can find out much HP your putting out with the TP. Your A/F should stay about the same, nothing dangerous -- at least that is the case with me

 

So will the ECU be able to adjust immediately and therefore the dyno measurement will be accurate?

 

I say do it and tell us the outcome. I am interested.

 

The ECU won't "learn" immediatly but in a week or so it will correct everything and you'll be fine.

 

So, if the ECU needs a week to learn, should I wait a week to do the follow up dyno?

I would like to do it immediately because the conditions will be nearly identical.

 

I would definitely do a before install dyno, just to get a baseline. As far as waiting I can't offer anything on that... sorry

 

My guess it that you won't make any additional peak horsepower, but you'll pick-up some mid-range torque/horsepower. Plus, you'll shave some weight.

 

You'll gain peak HP as long as power throughout the whole powerband.

Its probably not a week, I'm just saying that to be safe. The difference isn't very much between it "learned" and "unlearned"

Note that I made more then 15HP peak and 10 TQ peak with a testpipe. Plus HP and TQ gains throughout my whole power band.

 

Not trying to be an ass, but I don't believe your gains at all. There's no way a test pipe is going to make that big of a difference. "Different dyno, different day, different test condition, etc. etc. etc.".