Good to see ya gettin that goin.
What are your plans for the engine ports?
I feel ya on looking for good engine parts. I took apart 3 GSL-SE's and 3 REPU engines before I found descent housings. Now wich plates to port..?

 

Gonna follow Dan Atkins' advice for SC engines and go with stock intake port timing but big exhaust timing. My housings have GSL-SE exhasut ports so I'm going to enlarge to T2 spec. Just have to go down a few mm and widen by just 2mm on each side. I've done this before on my bro's RX-4 engine when it got an SC. Low end torque was fine. High end was a little lackluster due to the smallish exhaust system before I knew what I was doing. Now I'm building a 2.5" system.

Ask j9fd3s. RB recommends 2" on 1st gens and old schools but 2.5" on FCs. They sell presilencers in 2" for '85 and older and 2.5" for '86-'92. The 2" presilencers work well only if there are two of them (one for each rotor) like the dual pipe "streetport" system. You just need a quiet muffler like their powerpulse or primaflow.

I've decided to modify my original exhaust idea in favor of using two 2" presilencers and running them side by side, kinda like RB's 'streetport' system. Then Y them together into a 2.5" universal RB muffler. It will still be loud due to the dual pipes so I'll suppliment the rest with 2.5" magnaflows under the bed until it's quiet enough for me.

Ironically I may wind up spending as much on this system as I would have on the power pulse muffler, but this will fit a truck better.

 

I sold some parts to a local rotorhead so now I can afford the gasket set and other engine parts to get this rebuilt and prepped for an SC. I'll post pics as progress is made and time permits.

 

cool.. iv been selling my rx2 parts to finish my repu lol

 

I know what that's like. Been selling stuff for a while now to get enough parts for this. I actually have all the parts necessary to do a 12A in it right now. I've got one here that needs a quickie rebuild. Then it needs to be broken in in something. Why not?

 

so u should quickie build that 12a and sell it to fund the repu 12a's are history now and are in the past.. need to move forward hahaha. kidding.

not

 

Thinking more about it tonight, I've got a 13B that needs to be built and broken in in something. REPU! The 12A will go in something else for break in because I've got a 6 port 12A I'm interested in building next. Might as well convert it over now. Think about having low end of a 13B but good gas mileage of a small ported 12A. I wonder what the high end will be like if I give it a 'streetport' job on the low RPM ports?

 

I have the same set-up in my midnite blue RX-3: dual 2.25 pipes, RB 1st gen presilencers into a 2.5 RB universal muffler. Sounds very throaty (deep throat LOL) but I cant say if it will outlast other aftermarket mufflers as I hardly driven it.

Im also ditching the dual mufflers in my blue RX-3 and will replace it with a RB 3" universal muffler that I picked up from that *** with a green 4door RX-2 LOLLLLL. IT currently has dual pipes with RB universal presilencers which I'm not sure if they are blown also

 

I've been wanting the deep throated sound in the truck. Cool info!

Yesterday I lined up a whole bunch of mufflers and tested sound absorbtion with a compressed air blowgun. I had to wrap a rag around the nozzle to form a buffer against the opening of each muffler.

Let's see I had these mufflers to test...

3" Magnaflow 5x8 oval
2" half dead rotary engineering glasspack
2.5" RB universal muffler
3" RB universal muffler
2.5" RB presilencer
3" Large RB universal presilencer
3" Medium RB universal presilencer
2.5" 4" round Magnaflow (22" long)
3" 4" round Magnaflow (14" long)
2.5" Magnaflow 4x9 oval

From best muffling to worst, it went like this:

2.5" RB universal muffler (very best; stunning, really)
3" RB universal muffler
3" Magnaflow 5x8 oval
2.5" 4" round Magnaflow (22" long)
3" Large RB universal presilencer
3" Medium RB universal presilencer
2.5" Magnaflow 4x9 oval
2.5" RB presilencer
2" half dead rotary engineering glasspack
3" 4" round Magnaflow (14" long) (the very worst, almost laughable)

I didn't have access to any RB 2" presilencers for this test. I was suprised that the 2.5" was as bad as it was. But then I noticed the expansion chamber was interfering so I flipped it around and it muffled a bit better.

So the 2.5" universal RB muffler was the very best. Yep, deep throaty, like a pleasant sounding brown noise generator. Others had more a pink noise sound while still others had a white noise like sound. The worst of the bunch was the 4" round Magnaflow with the 3" core. I suspected it wouldn't muffler all that well, but it was so bad it was like it wasn't even there. It;s going in my '81 FB in front of trh rearend so I needed something that would fit in that small space. Sure it will fit but I'll need to redo it, suing the 3" core and rebuilding the outer shell to something that looks more like the outside dimension of an RB "Streetport" center section (4" tall on one side and 2" tall on the other, like a funny looking oval) to fit under the oddly shaped floorboard. You gotta do what you gotta do when 3" NA, you know?

So I think for the truck, since it's getting dual RB 2" presilencers, is to use the best muffler I have in 2.5", which is the RB universal, because I very much want the deep throaty bassful exhaust note that it had back in the day when I installed a poorly made dual primary system consiting of six rotary engineering glasspacks that Mark Moses built for a friend's REPU in '91. I got it in '97 and found out how crappy it was so cut it up and used the glasspacks elsewhere. One of them still survives today as listed amoung the mufflers above. lol But this truck did sound darn good! It just didn't perform worth anything.