anybody know the bolt spacing on a 4th gen Si CAT? I have a catback designed for an H22, so im told the holes in the flange of the exhaust will have to be elongated outward to fit my h23. How far? or do i just have to remove my stock exhaust and then proceed to guess and check?

And while i'm at it... any secrets or home remedies to remove the heat shield around the CAT? I've got 2 of the bolts out, but the other 2 bolts are rusted/stripped/decayed/ruined. I'm contemplating just taking some snips and cutting around the bolts.

 

well, if i wasnt at work i would go out to my garage and measure it for you, but it is off by 3/8th on all sides. It would be easier if you pulled yours off so you know exactly which why the holes need to be made.

 

3/8 each way should give me enough info i believe. Is this easy enough to do myself? They make drill bits designed to slot, correct? Just use one of these and slot over....

Between slotting the holes, having a 1" spacer made, and struggling to get my CAT heat shield off i'm starting to wonder if i oughtta just let the muffler shop do it.... any idea how much it would cost? I save money wherever i can, and like the experience.

 

had same problem I had to heat the bolts up with a torch. Just make sure you don't hit the cutting gas. and then they loosen right up for ya. They are a bitch though.

Peace

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by munscher &raquo;</TD></TR><TR><TD CLASS="quote">3/8 each way should give me enough info i believe. Is this easy enough to do myself? They make drill bits designed to slot, correct? Just use one of these and slot over....

Between slotting the holes, having a 1" spacer made, and struggling to get my CAT heat shield off i'm starting to wonder if i oughtta just let the muffler shop do it.... any idea how much it would cost? I save money wherever i can, and like the experience.</TD></TR></TABLE>

Well, it was a pain in the A$$ to do, so I just bought a high flow cat for like $70. Just get one for a h22. the part where the header connects to the cat is the same for h23 & h22. Just the exiting connecter is different.

 

i thought about getting a high flow cat... did $70 include the flanges welded on? And can i get a high flow cat that is a little longer to avoid having to use flanges as spacers to gain the extra inch? And i'm assuming they make 60mm high flow cats? (2.37" or whatever it equates to)... i usually only see 2" 2.25" 2.5" and 3" cats.

The other problem i thought about with a high flow cat is that i have a stock header. that means i'll have to get the smaller piping on the header side of the cat, so when i upgrade my header i'll need a new cat, correct?

 

i cant find the site i got mine from, but check this place out for an idea of a cat with the brackets attached. And hope fully someone else can give you the info you need as far as sizes go. as far as stock header vs. aftermarket. they both have the same flanges just the piping is different.

http://www.streetbeatcustoms.com/tucc108.html

 

how's this sound for an idea.... The flanges between the header and cat will match up regardless... so is there any adverse effect to going ahead and getting say 2.25" inlet on the high flow cat and bolting it to the smaller header? Obviously it won't help performance, since the air is still restricted at the header, but it shouldn't hinder it? That way i won't have to change it out later.