Exhaust combo for 3.2

[Jhogan0101]

Im building a 3.2SS.
It will have 46mm pmo carb w mod s cams.
Not sure which way to go with exhaust.
Seems that 1 5/8 looks like the best diameter from what i am reading.
Heat exchanger vs just headers pros/cons?
What brand is best for quality/performance?
Also looking for a quiet 2/1 muffler, any suggestions?

[cabmandone]

I'd get something with heat exchangers. The defrost is nice in the fall. I think a lot of people recommend the SSI's for the 3.2. B&B has a nice header with heat setup but their "muffler" won't fit your quiet requirement. Make sure you get 1 5/8 headers and not 1 3/4 if you go used. IIRC 1 5/8 is the OD not the ID. My brother is fighting tuning his PMO's and Richard is telling him he has the wrong headers and it's causing tuning problems.

[Lyle O]

I agree that you should try to get heat, living in PA (I live in Michigan and could not do without it).
I just completed a re-build of my engine (3.2 to 3.4). I used to have SSI with 2/2 M&K. On the 3.2, SSI (1.5") provided great mid range torque, but I frankly wanted it to feel more "on the pipe" at higher RPM. With the 3.4, I went with RarlyL8/M&K 1.625 headers, with heater boxes, and stayed with my M&K 2/2 sport muffler. I have to say I am blown away by the set up; sound and engine tune are great. The sound at idle it really nice, then it just screams (in nice way!) at higher revs. In terms of performance, it is a great balance of mid-range torque and higher end power. Very satisfied, and the heat is great. It plumbs up really well, even if you stay with stock heater blowers like I did (stock look in the engine compartment). Here's a shot of the set-up.
Good luck.

Lyle.

[rtu0894]

Lyle, nice setup. I have the same and ran into a situation with the heat ducting. I didn't want to do a full backdate either. It looks like you just cut a few inches off the 'y' tube on the right side, prior to the scat tubing and heat boxes. Thought about going this route as well. However, it seemed a little too 'visible' from the rear. Is that also the case with yours?

[sundevil64]

What about 993 HE's? I am have a set I have to flip the flanges on one side, but that is the route I am going to go for my 3.2 in my 73. You know it will work well. It's Porsche original. It is also fairly cheap.

[Lyle O]

Originally Posted by rtu0894

Lyle, nice setup. I have the same and ran into a situation with the heat ducting. I didn't want to do a full backdate either. It looks like you just cut a few inches off the 'y' tube on the right side, prior to the scat tubing and heat boxes. Thought about going this route as well. However, it seemed a little too 'visible' from the rear. Is that also the case with yours?

The "Y" tube is in the same relative position as with a stock HE, and is really not visible unless you are nearly at ground level. Below are a couple of shots of the rear of my car, one from about "mid-thigh", the other "below the knee". You only can see anything on the bottom shot. When I feel motivated I intend to replace the red tubing with high temp race ducting that is metalized (vacuum deposition over silicone/fiberglass). It looks like metal tubing but is flexible like SCAT and SCEET. Then there would be no contrast and not be noticeable at all. But the way it is now works well for me.
So what did you do?

[rtu0894]

Well... I had it mocked up but wasn't thrilled with the results. I thought it was too visible from the rear for my liking, so I took the aluminum heat boxes off and shelved them for a while until I regroup with another plan. I didn't do the oil line re-route, so that complicates things a little. I also didn't want to cut the stainless y pipe. Although, I'm sure I could always pick up another used one on this site if need be. I will probably cut the pipe and do pretty much the same thing as yours. I'll try and post some pics before and after when I do the deed. I actually had one crazy idea of fabricating and 'F' pipe where it first comes below the engine tin. Left side would be the same. Right side would have run SCAT tube initially toward left tail light then up and over and across muffler in bumper cavity down to the right box. It would work, but a little too 'mickey mouse' for me...

[Lyle O]

Originally Posted by rtu0894

...Right side would have run SCAT tube initially toward left tail light then up and over and across muffler in bumper cavity down to the right box. It would work, but a little too 'mickey mouse' for me...

I actually had this exact set-up (tube from right side running over the muffler into a modified left side Y) when I had the SSIs. It was fine, but I always thought there was a better way (as you have surmised). You can easily pick up nice used stock cross-over tubes for under $100 (I know I did), modify it, and keep the original (or vice versa).