I have an 85 GS and have purchased the racing beat header and presilencer. My plan is to install the header and the muffler and weld in a straight pipe between the two. Anything else I need to do to make everything right?



Can I just get rid of the cat(thermal reactor) or do I have to do anything to make it all work right.



Any help is greatly appreciated.

header and pre silencer takes the place of the cats and exhaust manifold. the stock rear muffler stays

Sorry, I have the header and the rear muffler that's it. Problem is the leak I am battling is in the midpipe. Can I just junk everything betweenthe muffler and header?

Yes, but it won't pass emissions.



If you take the cat out, you'll need to plug the hold on the rear of the intake. Racing Beat makes a blockoff kit for the intakes, or you can make your own.



As an aside, I had good luck passing visual inspection with a RB Header/Presilencer and an O2 sensor for a/f gauge at the end of the header. Nobody knows what a rotary should look like, but even the ones with vague knowledge will think it needs that big of a cat.

Thanks Chris, that's exactly what I was wondering.



So there is a hose or something that runs from the cat to the intake? What is it for? If I follow from the cat I can find what I need to block off? Can I block it off under the car instead of at the intake?

It's a solid tube from the cat up along the firewall, and there's a rubber hose that goes to a nipple on the back of the intake. I guess you could pinch off the tube and fill it with JB Weld or something, but its 2 12mm nuts on the back... not hard to make yourself a little blockoff plate. If you don't have the means or inclination I can make one, or I may be able to find one from an old RB kit around here.

Got it all in, blocked the hose off with a bolt and a hose clamp. Running RB header and Power Pulse muffler with 2" OD pipe straight through. I LOVE the sound, much quieter than my leaky stock setup, and the power gain is VERY noticeable.



Thanks for the help.