First, thanks grumppyvette for taking on some rather specific questions. Here's mine: I dropped my full exhaust this last time at the strip and put on 2 1/4 x 18 header extentions on my shorty headers and picked up a full second. I need a different exhaust and I would like to have it designed so it would have the same, or nearly the same power as open headers.
Here's the motor:
355 1996 pickup block (Chevrolet)
XR276HR cam with springs and full roller lifters
AFR 180 street port heads
Weiand stealth manifold with a 770 Holley street avenger.
1 1/2 Heddman shorties (Jeep conversion headers).
The chassis:
1986 RX7
4.10 gears
700R4, no stall.
I've read and read about primary sizes, tube diameters, etc., and I would like a plain english answer from experience on what would be the best set up.
Thanks, Jim.