I read in the racing beat catalogue that you can assemble a long primary system (for NA FCs) by using two pre-silencers (one for 84-85 GSL-SE, and the other for the FC) and a header...how does it work? Wouldn't that be too long for the Y-pipe to bolt on correctly?

Has anyone done this before? Feedbacks pls...

 

bumpu

 

They need to be more or less side by side. One presilencer per pipe. One of them uses the GSL-SE pre-silencer from RB because it has the exhaust backpressure sensing tube for the 6 port actuators. Their FC presilencer is just the same thing without the backpressure tube. You would only have one muffler out the back since your pipes will collect right before the muffler. It will still need quite a bit of custom work.

 

Rotaries love long primary systems, and you can use the two presilencers to tune the system. The length between each port and each presilencer should be kept equal, so the presilencers won't sit side-by-side but be staggered, with the front rotor's presilencer sitting further forward.
I would think doing the whole thing custom would be much cheaper than trying to mix and match off the shelf systems.