I was going to make a shroud around pull side cover and draw air from right side pan vent. I determined the kit would have to sell above $250. That won’t fly!
The Indy overheating problem
Indy Trails from 1986 with Fuji fan-cooled 433s and 488s had overheating problems. On warmer days and at slow speed operation power diminishes noticeably. The sled may stop and when cooled down it will restart. Some engines just seized. Not at all what owners expected from stone reliable Polaris engines and for the “wife’s” sled.
The factory ran the exhaust pipe right next to the engine intake fan. The air flowing over the exhaust warmed the engine compartment. Basically, the hot engine couldn’t cool because it was breathing warm air. The probability of overheating with a fan engine under my RXL hood is increased because fresh air intake is reduced by the non-vented RXL hood. The single source of fresh air are four 2” holes in the bulkhead.
1) Deflect the exhaust heat so it is not sucked into the engine.
2) Drill holes in the back of the air box so cooler air is sucked in from the left engine compartment side. This trick can be used for liquid cooled engines as well if bogging occurs.
Kill pipe heat on the cheap
Swain Tech is the only company on the planet who coats exhaust systems with ceramic. Ceramic (a stone-like material) contains heat inside the pipe. You can grab the pipe with bare hands when the engine running full blast. It’s called White LightningTM. It’s a .015” (about 1/16”) thick ceramic coating that fuses with the pipe steel at extremely high temperature. This cures the engine compartment heat problem so even a fan engine can be properly cooled. Exhaust heat radiation is reduces by up to 50%. Under car hoods-from 800°F to below 400°F.
This thick insulating layer contains heat inside the pipe but also increases gas velocity and improves scavenging. This combustion effect increases horsepower by about 3%. Against a similar stock sled, you’ll pass them every time because ceramic is “bolt-on” horsepower.
I hear you thinking
“Why not just wrap the pipe with bands of fiberglass heat wrap or Kevlar?” you say. Well I’m here to tell you, that will work until your exhaust system crumbles into rust pile. The problem is snow (water) gets between the wraps and rust immediately attacks the pipe--not a slick idea!
Swain Tech is the answer
White Lightning is white and gets ugly with use. The uglier it get the better it works
Have your pipes and headers sand blasted, then send them to Swain for White Lightning coating. The cost is cheaper than anything I could develop.
- Single pipes are $90-135
- Twins are $150-175
- Triples are $225-275
- Y-headers, about $35
The price may vary a bit.