Postive note for ATR 3" crossover

[ez at nova]

I have ATR's 3" crossover system and I also have a dump pipe on the car. I went to the dyno today and did my last run with the dump open. I actually made 1 hp and 2 lb feet less on that one. I guess the person I ordered the dump from at ATR wasn't kidding when she said I "didn't need it unless I just wanted it for sound." Just my personal testimonial.

 

[azgn]

do ya think possibly if you had changed the tune to compensate for the open dump you would have made more power?

You will flow more air and lean things out

Turbo cars do not go faster thru the exhaust..........regardless of what ATR says......

 

[ez at nova]

Originally posted by azgn
do ya think possibly if you had changed the tune to compensate for the open dump you would have made more power?

You will flow more air and lean things out

Turbo cars do not go faster thru the exhaust..........regardless of what ATR says......

hmm, I might beg to differ with your last statement.... pop an exhaust on a WRX and you gain 20 - 30 hp instantly (trust me, I did it).

Anyway, I did not touch a thing with tuning after opening it, and I also did not have them move the wideband O2 reader around to the other side to put it in my dump, so I didn't have AF ratio numbers. Still though, I was a bit fat with 800 O2's on the scanmaster on the runs prior, so if it would have leaned out from being freer flowing, I would have expected some better numbers on that run.

 

[UNGN]

Originally posted by ez at nova
hmm, I might beg to differ with your last statement.... pop an exhaust on a WRX and you gain 20 - 30 hp instantly (trust me, I did it).

Yes, but you are gaining 20-30 hp over some other exhaust, not an open dump.

 

[azgn]

I guess I miss your point.....an open dump will ALWAYS make more power than an exhaust system (on our cars)....you may have to tune it

( the more power your car makes, the more noticeable the difference)

 

[BobbyBuick]

I think the point is it flows .
are you talking the single muffler exhaust with two tailpipes

 

[ez at nova]

Originally posted by BobbyBuick
I think the point is it flows .
are you talking the single muffler exhaust with two tailpipes

Yep, the crossover system has the one muffler going into two pipes. I thought the true dual was overkill for the car, and too much $.

 

[1QIKV6]

How does the car sound during daily driving?

 

[ez at nova]

Well, it's certainly not super quiet, but if I flip the dump open, then close it, it sounds like a Lexus inside

The sound is very aggressive and deep, my only complaint is a bit of resonance around 3000 rpm (on a 45/50 mph road, before the car would kic into OD). It's much better with the windows open or top off, which is 95% of my driving in the car anyway.

Suposedly, this system is quieter and less droning than the single shot.