I ordered a cool head for my Banshee today. I ordered the standard domes, and the 20cc domes. My compression right now is consistent with the chart on the Banshee zone. I am at 125 psi, at approx 1200 elevation. According to the chart, the 20cc domes should bump the psi to 151.

Locally, the only High-Octane fuel I can get is 110 octane, in a 55 gallon drum, for about $225.

My questions are: Will too high octane hurt the motor? Also, I have heard of people mixing the high octane with pumpgas. How well does this work?

 

Actually, at 150psi, you shouldn`t need any sort of race gas. 93 pump gas will be fine (up to 160-170psi).

Too high octane won`t damage nothing, maybe it will be slightly harder to start when cold ...but no damage.

You can mix race and pump gas to get the right octane level you need. Usually, you run the lowest octane rating as possible (so it`s cheaper). You find the lowest by testing different stuff. Get the bike warmed up, drop some pump gas, from the very low end, gas it (wide open) and listen for any pinging sound. If ti does ping (detonate), mix some race and pump gas (like 25% race gas), same test, pings again. more race ags...etc etc.

But again, if you really are at 150psi, you should be fine with pump gas.

 

That is great news!
Actually, I always run 92~93 pump gas in all my machines. (It is supposed to be non-oxygenated) I hope this works with the higher compression! The NAC's catalog has (race gas) next to the 20cc dome listing, so I was worried.

When I had the head shaved on my Blaster, it really made a difference in power, I am hoping this mod will do the same for the Banshee. When I added a Dynoport pipe, it pretty much ruined the mid-hit, and didn't seem to add anything to the low end. The top end "seems" the same. It just does not feel as powerfull as it did stock, and I am hoping this head mod will add something the pipe took away. (Basically, I just love the sound of this pipe, and that is pretty much why I want to keep it)

 

Well, I got the CoolHead installed with the 20cc domes. I have about 150psi per cylinder, just as predicted. I only got to test it Friday evening because the weather has been crap since then!
I didn't hear a "ping" and it seemed to run great. I think I have nearly gained back what I lost when I installed the DynoPort 2into1 pipe.

If we get some decent weather, and I can get some high octane fuel, I am going to try and do a test with mixed and straight high-O gas.

Thanks guys.
phil

 

man if i bought a pipe and it took away power Id send it back no mater how good it sounded or looked