Exhaust question

I got this info from a website, anyone do this or care to comment?? Thanks



The first modification I recommend would be to create a complete dual exhaust from the individual cats to the rear of the car. This would eliminate the single secondary cat. The three cylinders on each bank of a flat-six engine fire evenly every 240 degrees of crankshaft travel. Since there is no overlap during this period, this eliminates the problem of one cylinder exhausting while another cylinder's exhaust valve is still open. So keep the two sides completely separate. This will result in the best flow with no reversal. Don't go too large on the pipe diameter, or you will slow the velocity of the exhaust and ruin the mid-range scavenge effect. I would recommend 2" exhaust as a maximum. Definitely do NOT use the 'most advanced new' method of using sewer pipe to conduct exhaust gas away from the vehicle. In some quest for the least amount of backpressure, these folk are missing the point that harnessing the velocity of the exhaust gases creates a scavenge affect that is better than zero backpressure.