The cats on my car are all rusted through and leaking. I'd rather not replace them with new ones as I don't have emissions testing where I live. I'm curious if there are any premade pipes that will bolt up to the stock header and delete all 3 cats?

 

Racing Beat use to carry them but I don't see them on the site. You don't want to remove all three. One is a cat but the other is a presilencer. You want to keep that or yuour exhaust will be to loud.

 

http://www.rx7.com/store/rx7/saexhaust.html

Your Shopping Cart

 

I just installed the Bonez pipe. It sounds decent, no louder than it was before with two burned-out cats.

 

A couple notes on the bonez pipe at RX7.com.

Their description is misleading, in that it says it replaces just the main cat.

The one I bought from them a few years ago, which looks just like the one in the picture, replaced ALL THREE cats in my 84/85 GSLs.

You may want to call them to ask for clarification on this point.

Advantages were:

1) an instant power gain
2) better gas mileage
3) excellent not-too-loud exhaust note
4) fixed the leaking exhaust problem
5) $150 from recycling the cats, enough to pay for the pipe, installation hardware and shipping

And it only takes an hour or two to install.

 

"And it only takes an hour or two to install"



Sure, if all the exhaust shield bolts aren't completely rusted, or the middle cat support completely fused. My mistake was not using a bolt splitter from the start. That would have sped things up considerably.

 

I should have qualified that. 2 hours for a Georgia car, which has no rust. 12 hours or more for the Canadian vehicles!

 

So the Bonez pipe would probably be my best bet? And yea, being in Missouri, cars around here get a lot of rust from our heavy salted winters. Changing my muffler was difficult enough.

 

The price is certainly right. $75-$100 for a bolt-in replacement is decent and the noise level is tolerable.

 

Is there some kind of presilencer in the Bonez pipe? I used to have a Racing Beat straight pipe and that sucker would wake the neighborhood up when I cranked the car up. It got better when I replaced the muffler with a RB unit, but the car didn't get tolerable until I hooked up the full RB kit.

 

The Bonez race pipe essentially is a presilencer, see that bulge in the middle?



Hooked up between the stock exhaust manifold and the midpipe (replacing all three cats) and coupled with the stock muffler, it yields a very decent exhaust note, just slightly throatier than the stock system but not at all obnoxious.

 

150$ isn't bad. I just took the big main cat out and measured the overall length. Cut the flanges off and welded a pipe in the same length as the cat and bolted it back in. I ended up just howling out the front cat. Wich ended up being free and ingot like 120$ for the scrap cat. But I would think the pipe would be better since you would probably get better flow rather than it going into the first cat and bouncing around before going threw the rest of the exhaust.
Luckily my car has the cleanest under carriage I've ever seen and all the bolts broke loose with ease.

 

I just installed one of these on my 81. replaced all cats and fit very well. no real increase in sound.