Review: ACM Test Pipe and ESS Tune...trading cats for horses
Prior to adding test pipes and tune I had Dinan Rear, AA Filter and RPI Scoops performance wise. I got the Dinan because I didn't want drone and because it was a relatively quiet exhaust it would always leave the option of going catless without being obnoxiously loud. When ACM (a local shop for me) decided to release test pipes it became a no brainer.
I installed tune on it's own first and had it for about a week before the test pipe install. I went from 080E (I've got a 2008) so ESS gave me two files - one to go to 240E and then one for the tune - setup for catless, no cold start and no rev limit. Also doesn't show CEL for no cats. Why ESS? Well ACM was doing a promotion with pipes+tune together and for me, ESS is a proven dedicated tuner, just look at all the SC kits around.
Having had the car for a year, I'm pretty familiar with the feel of acceleration - after applying the tune you can definitely feel a difference. Even in low RPM it felt more peppy and it would pull harder above 4-5k. It provided some new life to the engine for sure. Whether I would get the tune on it's own is debatable, ultimately I feel it's a must if you go catless to help maximize performance.
ACM Test Pipes:
I expect these are quite simliar to turner and MS pipes, where x-pipes have a lot of varieties with resonators, HFCs etc - test pipes have a pretty simple assignment: Replace those bloody cats! The test pipes are tremendous value IMO - you get all the power of a full x-pipe, but you also don't go crazy loud nor do you get any wack smells since the secondary cats are still in place.
Sound...wow. This is the sound I've been dreaming of and all the youtube videos can't do it justice of hearing it in person. No drone, quiet when you want it to be which means compared to just axle back if you're just driving around town there is almost no difference. WOT - different ball game. It's probably 30% louder but it's also the quality of the sound which is most pleasing. The Dinan seems to limit raspiness so it sounds pretty smooth yet aggressive. It really screams and and w/ added power it rips into the high revs freely. Where the Dinan alone add some volume in low RPMs, at high rpms it wasn't much different from stock - you'd get a lot of engine but not much exhaust. Now volume increases in tone and pitch as you race to 8k which is more what I'd expect.
Powerwise - I'm very happy. I was skeptical of whether 20hp from a tune alone could be felt on a 400hp car, but because it does change the overall dynamics, it made the car more enjoyable and the power could be felt. Couple that with the test pipes and you have a very very rev happy car. Every gear just feels much stronger. Not mind blowing like a SC'd car but it's a very nice bump in power. It's probably coupled with weather getting cold but I found before if I accelerate from slow roll in 2nd, I wasn't likely to get wheel spin but now doing the same thing it will tend to break traction at 5k+ which is kinda cool and scary =)
Thanks to Sal+Lalit @ ACM and Asbjorn @ ESS for helping me through all my questions.
btw if anyone knows of a basic windows app that can trim/edit mp4 files I can post some of my gopro clips.
[08 e90 M3. Jet Black/Black. Dinan Rear Exhaust. ACM Test Pipes. ESS Tune. Eibach Pro-Kit + e36 bumpstops. 18x10 Apex Arc-8. AA Air Filter. RPI Scoops. CREE Angel Eyes. OEM Blacklines. Black Reflectors. Gloss Black Grills. Matte Black Gills. ZCP Shift Knob]