I just got a cat-back made, with stainless Edelbrock RPM mufflers. With the cat still installed, it sounds GREAT! (actually has a nice low rumble in low rpms!)
With my Bonez race pipe w/prescilencer in, it sounds like the loudest weedwhacker out there. Garbage.

How is it that the prescilencer can be way louder than a gutted cat (which I had at one point)??

Anyways, my question: What do you think would make more power.
-Stock manifold with a staright pipe /prescilencer (no cat)
or
-Headers with a Cat
I have a street ported engine, which they strongly recomend headers on.
The reason I don't want to go with headers and straight pipe is because it is SO LOUD right now (the car shakes!) and headers just make it louder... Is it worth the power gain?

So, what would be everyone's opinion on the choice??

Thanks for your input...

 

Just some info. On my 82 some years ago, I installed the RB header and presilencer. I ended up with that tinney sound. I then got the mufflers to match the header and presilencer from RB and its a totaly different sound. Deeper more robust. Thats why on the 87 n/a I bought the whole package from Mazdatrix..dual system from headers to muffler tail pipe. I think I'm trying to say it helps to have a matching system. I think RB must *tune* the mufflers to match their presilencer and headers. Just my thoughts. I realize that you have dough tied up in the present mufflers that you have.