How much smoke is visible out of the back with a test pipe? I have a perrin catback and would like to throw on a test pipe, however, I do not want a gigantic smoke screen at idle or when I go WOT. My prior car, eclipse GSX, with a test pipe did not smoke at all, but its tune was not as rich as the evo. Any thoughts?

 

I'm running a tuned X with the stock cat installed and under WOT it still puts out a pretty heaping cloud.

There are a few tuned catless cars that I have personally seen on both a Dyno and on the road. Under regular driving conditions they don't put out any smoke...but under WOT they put out about the same as an untuned X w/cat. Now, keep in mind that these cars are still in the mid to high 10s as far as AFR goes.

My recommendation would be to stick with the OEM cat until you can get the car tuned. You won't completely eliminate the smoke...but the tune will help reduce it.

Most of the Xs in my area were well into the 9 AFRs (some even in the high 8s!!). My trunk was COVERED with particles from the stock setup.

 

why do u want to put a test pipe on without a tune?

 

No smoke out of my exhaust. Just the occasional fireball.

 

Why not?

I want to get Accessport, but would rather have all of the supporting mods before I purchase it.

 

I got tuned a month or so ago, and just installed my test pipe yesterday and I have massive fire ***** at wot and love it. Not a lot of smoke though, I'm going back for a retune at the end of the month and hopefully I'll be able to squeeze some more power out of this puppy.

 

And you're untuned? How about an mbc?

 

AP will have a tuned map for stock.... so you could just get the AP first then the test pipe.

seriously thou, test pipe really isn't needed... might as well save the environment a little

 

Man, all this guy wants to know is if he can put on the test pipe without a retune.

Big T

The answer is yes, it's fine. Your car will not end up like the 07 Imprezas that blow up with turboback exhaust. It is perfectly fine to install a test pipe without a retune; however, I do recommend you get the tune eventually. Under normal driving you will not get a huge smoke cloud.. c'mon the cat doesn't do THAT much. AND, under WOT you will get a decent amount of smoke because your ECU is telling the injectors to dump fuel.. but this amount I don't think you'll need to worry about. Drive behind a stock evo and tell them to floor it and you'll see what i'm talking about. yes, the stock car does it too.

Test pipe installs take like 20 minutes. If you dont like it, simply take it off. But, that will not be necessary.

hope this helps

 

I have all the mods listed in my signature and I'm on the stock tune (at stock boost level). Granted, I'm getting a tune as soon as I can get an appointment and I don't go WOT very often, but you'll be alright with just a test pipe.

 

I didn't think that the test pipe even added that much hp? For me it's easier to leave the stock cat on because every 2 years I have to have emissions checked. For a few hp i'd rather not worry about it... also the downpipe for the X's are supposed to flow really well. Didn't AMS or someone make one of their own with no gain over stock?

 

I think you're referring to the non widemouth version.

and the test pipe DOES make a noticable difference, as does the UICP.

As for you.. get the AP.

 

with or without test pipe, makes no difference. your car will smoke like before - the cat makes no difference on that matter.

a TUNE will get that smoke out, however.

 

oh it does add considerable hp, but i suggest you went like i did and get a high flow cat. my car still registers a cel for cat efficiency despite the cat, so i had to add a spacer to get rid of it.

the downpipe alone makes no difference whatsoever; those that are selling just the downpipe (i.e. greddy) are just gimmicks. the o2 housing does. but you'll never find an o2 housing by itself - literally every aftermarket housing out there includes the downpipe.

 

Ok then, i'll go with a test pipe.

My old car, 97 GSX - big fuel system, TD06 20g turbo, built head, dsmlink, etc - didn't smoke at all and I had a completely free flowing exhaust including open dump external wastegate. However, the AFR's were in the mid 11's and I know the evo x runs much richer then that. I guess i'll just give it a shot and if I don't like it, throw the stock cat back on.