Hi flow Cat Converter vs. Gutted Cat Converter

[LM1999]

Will a gutted cat converter help spool the turbo faster vs. a hi-flow cat. This is with a stock turbo now but want to upgrade to a ta49 te44 with .63 Garrett housing. I don't want to change the stock D5 converter. Also, car has 2.5" GNX type exhaust with dynomax mufflers.

 

[49-blues]

I think the least amount of restriction could only help spool up.

 

[Roc87]

I have a "hi-flow" cat for that one day every two years when the GN has to pass emissions, and it's very easy to tell that there is a restriction in the exhaust.

 

[LM1999]

i don't think I require an emissions test for the car. Even if I did, it is every two years. Is there a noticeable increase in exhaust noise w/o the cat? Also, once the car reaches operating temps, will the turbo's heat help improve the exhaust odor w/o the cat?

 

[Roc87]

My GN has the hooker exhaust on it, can't really tell much difference in exhaust sound/tone running the cat or not. If it's tuned ok, I doubt you have much odor out the tailpipe with no cat, but doubt the heat off the turbo would have an effect.

 

[Adam Connell]

I just gutted my high flow cat... noticed a nice difference. Car is much more responsive now.

You guys do know that all TRs are now emissions exempt right?

 

[Hot Air]

I have a custom 3.5" downpipe, Random hi-flow cat, Dynomax race (loud) muffler, and tailpipe...all 3.5". I have to tell you that I have way more power (check out my signature) than I can use on the street! I do have a straight pipe that I can change out at a minutes notice. I had Jack tune the motor with the straight pipe and I installed the cat as soon as I got the car back to NC. I have never pulled the cat to re-install the straight section. Maybe it is the 3.5" cat but it runs great! My biggest problem by far is getting traction!
Hot Air

 

[Brady87GN]

i don't think I require an emissions test for the car. Even if I did, it is every two years. Is there a noticeable increase in exhaust noise w/o the cat? Also, once the car reaches operating temps, will the turbo's heat help improve the exhaust odor w/o the cat?

No, you won't require a e-test. I bought my GN in October 2010 and it wasn't required to get plates, validation or insurance.

 

[Roc87]

You guys do know that all TRs are now emissions exempt right?

Still depends on what state:frown:. The county I live in requires emissions on every gas vehicle made since 1975! Not only that, but vehicles made in 1975 through 1984 require the test EVERY year. Of course I live in the ONLY county in the entire state that has emissions

 

[berserker6]

i believe we have one more year of emissions testing here in jersey. its not the emissions that concerns me its the visual inspection.

 

[87 national]

i believe we have one more year of emissions testing here in jersey. its not the emissions that concerns me its the visual inspection.

I live in jersey they only do emissions now no more visual inspections so your good.:biggrin: