Exhaust porting

It's no secret that the stock exhaust system on the Mad Force is, let's say, sub-optimal. I already showed on the first run General Issues page that the header gasket blocks a lot of exhaust flow, a problem easily solved with an Xacto knife. When doing a thorough cleanup of the truck after my first few weekend runds, I decided to take things a significant step further and bring out the Dremel to do some serious damage.

My main focus was on the header, itself. The inside of the stock piece had a sharp turn and a couple of hard ridges that surely created a lot of unnecessary turbulence. I simply used a round-tip grinding wheel to slowly smooth all of this out at both ends, venturing deep inside with the tool to ensure continuous radiuses. After these pictures were taken, I came back with some medium-grit sandpaper to smooth the surfaces a bit more still, and then gave them a quick polish with a bit of rouge and a buffing tip on the Dremel. I even ground off the threads on the left side screw which, by design, has to protrude smack dab through the middle of the exhaust flow.

I then went ahead and took apart the stock muffler and softened, rounded and polished all edges in it. The end result certainly looked nice, regardless of whether there would be any change in performance.

The next time I ran at the same track, I was able to do wheelies just slightly easier. Before, due to my low CG and small tires, wheelies were actually pretty difficult to pull off. If I had to guestimate, I'd say the power gain from bone stock to ported & polished was somewhere in the range of 5-10%. Granted, this isn't much of a change, but it was enough to notice a slight difference. Considering the cost ($0.00 US), I can't complain!