black79

I have a 1979 SA that I am putting a 13bt into. I was wondering what other have done with the exhaust issue. What is the best choice of exhaust? Will the 2nd gen exhaust fit under my car or should I build or have built a custom exhaust. The exhaust on my car is in good shape but stock 12a exhaust isn't really big enough for a turbo application is it?

7aull

iTrader: (2)

I would think the stock 12a system could handle the heat of the turbo, but its pretty restrictive, even for 12as! Can't help with the header-block interface, but from there back a 12a Racing Beat system would fit the bill (literally). And RB makes 13B headers so if you can get the header to "talk" to the 12a RB Presilencer, your golden. All the OEM hangers all the way back fit it perfectly, plug-and-play.
Stu Aull
80GS
Alaska

trochoid

iTrader: (6)

Full custom single, 3" if you have any upgrades, FCD, ported wastegate, R-Tek, hybrid turbo or if you plan on upgrades.

black79

thanks for the replys and suggestions. I think I need a little more info though. Will the stock 13BT exhaust manifold connect to the RB 12A exhaust or will I need to make a new flange? Also is the RB 12A exhaust a larger diameter then stock? This engine is stock 13BT no mods and factory turbo. This is just a toy for me and I don't want to through a huge amount of money at it. Whats the cheapest route to go?

trochoid

iTrader: (6)

Stock SA/FB exhaust is too small for the 13BT. I'm running a full mandrel bent 3" on my 12A 1/2bp, but that system was built in anticipation of the pending TII install. Don't cheap out on the exhaust. An exhaust upgrade is THE 1st performance mod for any rotary, NA or turbo. Even the 12A RB system will choke and reduce performance on the 13BT.

Since the 1st gens have a single outlet system, FCs a dual, you should be running no less than a 2-3/4" system, end to end, 3" is better. When running a full 3", you will also need an FCD and have the stock wastegate ported to reduce boost creep.

black79

okay thanks but I think you lost me there. What is and FCD? Also is the anyone who builds a 3" exhaust system for an SA or do I need to build it myself? Building it myself isn't too big of a deal but I don't have access to mandrel pipe bender and i would have to crush bend all the tubing.

trochoid

iTrader: (6)

FCD=Fuel Cut Defencer. It is an electrical unit that lies to the ecu about the boost level so the ecu doesn't go into fuel cut. As soon as the exhaust is opened up, the stock systems overboost. Not a problem if one uses and FCD and ports the waste gate. No one makes a turbo exhaust for a 1st gen, it will need to be custom.

If you look around, you can buy mandrel bent tubing if you're building you own exhaust. My 3" piping came from a Ford turbo diesel recall program on the intercooler pipes. lol

Btw, which 13BT are you installing? There are differences and my info may not be correct for what you need.