Well the old thermal reactor was shot and was replaced with a Racing Beat Header and presilencer this week . I didn't order the RB cat back muffler

So it sounds like an angry swarm of Bees getting to 6K , does this go away with a RB cat back added??

 

Yes, it does. The stock muffler with RB header and presilencer sounds horrible in my opinion.

 

They don't refer to it as a cat back muffler, do they? I've never seen it refered to as such. What you want is their 79-80 muffler and you'll use your stock connecting pipe. It will sound good.

 

They just call it a muffler. The combo sounds great together.

 

on the racing beat website, when you go to sa/fb and you look for muffler it says "cat back exhaust"

 

Does it? That's weird. Well, maybe not so weird considering their mufflers fit in the stock location and can technically be used with a cat. However knowing how restrictive the stock cats are, upgrading just the muffler isn't going to net you a whole lot of stallions.

The rule that I think I've come up with is a stock muffler should be ok to keep using if you still have the stock cats and exhaust manifold. The cats are the most restrictive, followed by the stock muffler., The exhaust manifold, it turns out, isn't really very restrictive. Surprisingly, it flows fine on a friend's large streetported 13B with a 7" Camden SC. The rest of the system just has two Rotary engineering glasspacks and one dual tip Monza at the end. Not as loud as hyper4mance2k's car, but flows way better than the RB header+presilencer+stock muffler I had on my car, with a slightly milder streetported 13B and a 5" SC. I began to envy his manifold system. The sound and performance were seemingly better. I don't think I'll wind up using it though.

Food for thought? I'm kinda hungry.

 

i'm actually tempted to buy an RB muffler.. see if it makes my car sound better. meh stock still works. it actually sounds beefier than my friends' rx7s

 

Jeff, the 79 didn't have a cat , just the thermal reactor and heat exchanger , air pipe etc. both gone now , incuding the air pump . I guess I'll order the RB muffler , should have in the first place I guess .

and I might try putting a High Flow cat like the BONEZ that I put on my 89 vert , Maybe stick it between the presilencer and the muffler . I would like to get rid of the BEE'S , and maybe a bit of the smell . Has anyone ever put one of these on their SA or FB ?? . Not too concerned about a couple HP here or there . The SA is still a lot of fun at stockish HP.

 

I haven't run the Bonez on my FB, but the exhaust setup I had on my 91 was stock manifold, Bonez high flow cat and the RB catback exhaust. It boosted power quite a bit, and the exhaust sounded like pure sex.

I've been debating what I want to do with my FB's exhaust. I'd like to get a full RB kit, but I'm poor and may do it in sections. I just have to decide if I want to buy the header/presilencer first, or the muffler first. I want a little more power, but I'm tired of my car being so freaking loud too.

 

Just get their universal muffler. Its not bolt-on, but it will sound nicer and flow better.

 

How did you know the thermal was busted? I think I might be having exhaust back pressure issues could it be the thermal?

 

Visual inspection is the surest way. Exhaust gas blowing out the front cooling air inlet & cooking the ACV is the other, but that won't happen with all possible failures (like an insert collapse).

Bummer is that it's virtually impossible to remove/install the TR without also pulling the intake manifold (and thus draiing coolant), due to size and position of the top two nuts and the shape of the reactor. Mazda made a special removal tool for the top TR nuts, but it's not available.

Long ago, I found some smaller-outside-dimension nuts that replaced the stock ones, and that I could get to with a flex-socket.