hey guys...ive got another problem now...(nothing unusual)

ive got jdm 4-1 header with vision b pipe and spoon n1 muffler...with hi flow cat on...

now the problem is...on the 1st and 2nd gear when im revving at 4000+ rpm and let the accelerator off without changing gears...as the revs goes down...my cat seem to make a rattling noise...and when i took it to the exhaust workshop they checked the exterior of it and noithing seems to be wrong....so they assume its internal....and yeah...they said "all after market cats are like tat" so yeah...is this true?? if not wats a good aftermarket cat?? hi flow cat tat is...and also...

ive heard from some ppl tat with the exhaust setup i have....the best cat woulkd be stock cat...as spoons exhaust was tuned using stock cat and hi flow cat would decrease its performance...is this true??? should i change to stock cat??? wat would be the best cat to gain maximum result??

thanks for ur help guys...u guys know ur stuff...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by snb18c &raquo;</TD></TR><TR><TD CLASS="quote">hey guys...ive got another problem now...(nothing unusual)

ive got jdm 4-1 header with vision b pipe and spoon n1 muffler...with hi flow cat on...

now the problem is...on the 1st and 2nd gear when im revving at 4000+ rpm and let the accelerator off without changing gears...as the revs goes down...my cat seem to make a rattling noise...and when i took it to the exhaust workshop they checked the exterior of it and noithing seems to be wrong....so they assume its internal....and yeah...they said "all after market cats are like tat" so yeah...is this true?? if not wats a good aftermarket cat?? hi flow cat tat is...and also...

ive heard from some ppl tat with the exhaust setup i have....the best cat woulkd be stock cat...as spoons exhaust was tuned using stock cat and hi flow cat would decrease its performance...is this true??? should i change to stock cat??? wat would be the best cat to gain maximum result??

thanks for ur help guys...u guys know ur stuff... </TD></TR></TABLE>

Not all aftermarket cats rattle, especially new ones. My first guess is heat shielding near the cat.

I wouldn't worry that Spoon is 'tuned' to run with a stock cat. Got a dyno near you?

Good luck.

 

Cat problems? Get the Tabby Tote

 

ive check the heat shield and nothing is wrong with it....seems to be alright...but the internal rattling on the cat is worrying me...is it alright to take it to track with it??

 

Chris and Mike,

That's some funny @$$ sh@t!!!!

 

Your first post gave me a headache slow down or use the spell check

sounds like a heat shield is loose

 

Hopefully your cat doesn't wind up like this



might explain the rattle though

 

if you're pretty sure its coming from within the cat, just take the cat off and visually check the inside. Sometimes some of the catylist material will break off and rattle around in there. If thats the case then you should be able to get the broken part out and your problem will be solved.

I had a huge chunk of mine break off while I was on a trip and it clogged up the exhaust and stranded me.

 

what brand of high flow cat are you using?

 

My guess is that the rattling is actually coming from the resonator on the vision bpipe, not your cat.

The vision bpipe is known for that...I know a lot of guys who have had problems with theirs.

 

Yea i had a friend who had the same problem on a lude. turns out the baffling in the bpipe came loose and was rattling.