hey i just installed my rrm header and downpipe on my 04 ralliart...so far everything is ok except for i can feel a little bit of air seeping out in between where the end of the downpipe connects to the rest of my exhaust...i drove the car once i was done and nothing seemed wrong and ran fine..any tips? also the car sounds alot more raspy when i accelerate...would the high flow cat get rid of the raspiness?
any ideas would be greatly appreciated....thanks

 

Yes a high flow cat will definitely get rid of the raspiness and the backfires. I just have the downpipe with no cat and it pops and rasps like crazy.

For the leak you can just get an exhaust gasket if you haven't already, that or you can leave it. Personally since its after your O2 sensors it shouldn't affect anything much, just make sure your bolts are tight or just loosen the whole assembly and reseat the connection to see if that helps. Sometimes rust might be preventing a solid seal.

 

+1 on checking your seal to make it tight

I have the hf cat on my car and yes the raspiness does go away and the whole exhaust system will be MUCH quieter

 

i dont mean to thread jack, but had anybody tried using a HF cat and a resonator to try and quite down the header/dp?

 

Hey yeah I have the hf cat with my RRM header and dp but I don't know if I have a resonater cause I have the RRM catback as well but it sounds really good once it gets settled in... Nice and deep

 

i loosened it up and tightend everything again but it is still leaking because the flange is all rusted up... u can feel air on the top and bottom of the flange, not by where the bolts are...is there anyway to fix dat? i know dis is a stupid question but would double gasketing help out? the leak is in between the downpipe connection and catback. since its before the 2nd 02, would it rob me of anything?

 

th != d

Did you reuse or replace the gasket? If you reused it, what condition was it in? Try a new gasket. Also wouldn't hurt to clean up the flange with a wire brush.

 

i replaced it with a new gasket and i also cleaned the flange before i connected it...it seems like it might be an uneven seal....so i dont know wat to do

 

You might be stuck with it, but it should seal. Are you tightening it enough? Those bolts should be around 60 ft/lbs, or possibly a bit more.

There's no harm with having the leak in that location, though.

 

ya its tightened pretty tight...i think i mite put some muffler cement on it...hopefully it should get rid of the leak...but as for the high flow cat, are there any downsides to it or is it worth the spend for it?

 

the cat I can't really see any downsides... unless you care about like... the 1-2 hp you'll lose but its not significant...

 

+1 no down side to adding a cat if anything it will make it sound better and it won't back fire. I guess if your worried about 1 hp then maybe its bad. Up to you I guess.

 

i think i am goin to get the HF cat...cuz it sounds super raspy at low rpm but smooths out at higher rpm...but as for the install....how hard would it be? does the downpipe need to be cut in order to weld the HF cat?

 

Yeah you're basically going to take out a section of the downpipe and replace it with the cat welded in between the pieces. I'd recommend having a shop do it

btw you're in illinois? i wonder if you're one of the ralliarts i've seen recently

 

Why would you cut out a section of the downpipe? Why wouldnt you jsut put it after the downpipe and jsut cut the tubbing?