Why you tune for mods!
 

Tuned a car today that had a p&l header, perrin full CAI/elbow, cat back/overpipe. A relatively common setup, but it really showed how slapping hardware on does not equal fast. First pull on the dyno? Not so hot. AFRs are in the 10's from learning overshooting the targets.

http://www.moto-east.com/dynos/ft86/pc_stock.jpg

Next step is to go ahead and put the "base" off the shelf tune in and correct the MAF scaling. Now we're looking a little better.

http://www.moto-east.com/dynos/ft86/pc_tune1.jpg

Next up is tweaking the cam timing even further to take advantage of the header.
http://www.moto-east.com/dynos/ft86/pc_tune2.jpg

Though the base header calibration gets it close, we're working with the p&l/fa20 type of using the big loop crossing over, and this one has a cat in it. So we know down low it will really shine and up top we are only going to get so far. So we optimized the cam timing a bit further and got to this point.

http://www.moto-east.com/dynos/ft86/pc_tune3.jpg

So as you can see there was more to be had down low. After that we carefully reviewed the datalogs, and started to scale back the timing a few degrees, and up it a couple to see how close we are to the knock cycle. In this case 4 degrees delta made for 1-2 hp. That means you are far better off pulling those 4 degrees and leaving the extra margin in there in case it gets hot. After gaining nearly 30+ hp in some spots, that 1-2 hp means nothing performance wise, but makes sure that the ECU doesn't start to pull too much timing and taking even more performance with it. So the final plot vs stock:

http://www.moto-east.com/dynos/ft86/pc_final.jpg

Not a small difference on a 2700lb NA car by any stretch. We also put in the revised transient tables to take care of the tip-in knock you could hear on the stock tune despite the A01C revision it came in with!

Happy modding!

This is the kind of information I like to see. This is the whole reason I got a tune when I got my JDL UEL. These bolt ons are nothing without it.

:eyebulge::eyebulge:

Very nice to see detailed progress plots. Posts like this have been very slim. Thanks for sharing! Those gains are quite decent!

Great job Mike!

Thanks for the write up Mike, explained all the questions I had without asking. Shame it was so crappy out today, couldn't really get on it good.

Can't wait to go get some E85 and try out the 4th map!

And this is why I've decided to go with you guys for my tuning this spring.
Looking great!

Any chance you have charts with a/f logged as well just to illustrate how bad the a/f curve would've been before tuning?