[rcweingart]

Here's Peter Brock's thoughts about the fans and open side pipes vs. rear exit exhaust:

The twin rad fans are designed to suck air through the radiator (in the same direction that the air naturally flows) In at the front and up and out over the hood. Having the fans reversed from the factory is a common quality problem that should have been caught by the installer. Note the skid plate fans are designed to blow air DOWN and suck the heat out of the engine compartment. If you reverse these to suck air UP (as one might think this the natural flow of hot, rising air) all you'll get is lots of dirt in the engine compartment and very poor cooling, as there's nowhere for the air to escape! Except the side and hood vents and they aren't hat efficient.especially with the screens in place.

(r)ear exit exhaust *** constricts the exhaust flow and keeps the heat up front. *** (Open) side exit exhaust *** get(s) rid of all the back pressure and heat caused by a tailpipe system that's poorly engineered. (not to mention the poor ground clearance) The "S" pipes that lead from the sides to the rear actually decrease in diameter which restricts flow and retains heat. A proper rear exit system could be devised but the cost to make a proper system, with constant area "S" pipes and larger tail pipes just isn't economically feasible. I've tested cars with rear and side exits and there is NO difference in DB levels once you are on the road. Start-up is louder with side exit as the pipes exit right under you window. But once moving ..no difference.