I am very interested to hear experts weigh in on this. I have B&B 1.75" headers on my 3.2 - which consensus says are too large, but longer primaries? -I think should be 1 5/8" on a street car - although B&B still sells this as the right size for 3.2. I won't know for sure until I dyno the car, I am bringing a club sport car back to street. I also have stock exchangers, premuffler and sporty exhaust ready to install. My original thought was club racer wanted full hp at high rpm, I would want lower/mid range.

Please post how this turns out

Darrin is right, get it from the source (Brian), but Rarlyl8's headers are optimized for top end power. They are a wonderful design, and do the job they are intended to do.

Interesting thread. I just became aware of the Patrick Motorsports modified Billy Boat headers with heat and 38mm internal diameter. Being able to use 2:1 mufflers is key and in my mind is a bit of a game changer.

As someone who has a car that is primarily for the street, but does HPDE, I am always looking for the "perfect exhaust." I got SSIs because I wanted heat for my 3.2, and Steve Wong data suggested that they improved midrange, and top end over stock with cat bypass. Add the quality, and weight savings, and I was sold.

Then I ended up going 3.4L (964 cams so no crazy overlap) as I had an unexpected rebuild. With the SSI's I know they limit my high end power, but we have a tighter track and I must say that my corner exit speed is impressive. I only get the change to redline 5 times a lap, so I need to evaluate the benefits of larger primaries given that it is not all about max hp. 3.5-4.5K is very important in my car at our track.

But the PM BB's with their longer primaries and 38mm I.D. have the same I.D. as the stock exhaust, and the length and ID should help heep mid-range grunt while still giving a high end power bump. Bonus is that they save about 30lbs over the stock heat exchangers and cat, and are still lighter than the SSI's by 4 lbs. Cost is the largest downfall.

I have been researching 993 HE's with flipped flanges. they are only 22lbs total, but you need to get the custom welding, and also adapters for the larger heat exchanger ports. Finally, you need a customized muffler to make it work. Would be great if I could get one already done up with say a Dansk Sport.