I designed a muffler add-on for a neighbor's Honda Forman that worked very well. We went into the city one weekend and purchased four mufflers at a Midas Muffler shop with the understanding that we could return three of them. The muffler shop manager even let us go back into the stock room and hand select them. We had already taken lots of measurements and sketched the possibilities before we set out for the city.

We ended up with a set-up that worked even better than our expectations. We found a car muffler that was about 23" long with a very small (I don't remember the exact size) inlet and outlet. The inlet connection was a 90 degree elbow one way and the outlet was a 90 degree connection the other way. This provided a perfect connection to the existing Honda muffler and allowed the car muffler to be installed across the rear of the ATV. The exhaust outlet aimed down toward the ground at about a 45 degree angle at the opposite side of the existing exhaust outlet. I welded two 3/16" x 1" straps to the muffler that attached to the brackets under the rear deck on the ATV. It seemed to be perfectly made for this application. I used two 3/8" bolts with wing nuts for easy removal and a small U-bolt to clamp the muffler onto the exisitng tailpipe. It can be installed or removed in about 3 minutes.

This is without a doubt the quietest ATV we have ever heard. All you can hear are the engine internal parts now. It did not seem to have any effect on the performance of the engine at all.

Worked like a dream.

I'm getting ready to buy my first ATV and you can bet that I'll be looking into the old double muffler trick for mine too.

I don't have any idea what car it was intended to fit. We didn't even discuss a car make or model. We were allowed to go into the stock room and rummage around until we found what we thought we wanted. If memory serves me right, it wasn't 23" long. I think it was more like 18" long.

I recently bought a new Polaris ATP 500 and I'll be looking into an ad-on muffler for it soon. I'll keep you posted. And I'll try to remember to take pics.

No mater what - I would never pay $200 for a stealth muffler system. I think my neighbor only has about $40 total in his and it works perfect.