There are a couple of you out there that I figured would for sure be able to give me some answers on this, but to keep from hurting the others feelings, I'll not mention names. I have a couple stock heads for my R and I have had one of them very slightly shaved so that it still runs fine on pump gas, but I want the other one to run strickly with race gas. How many cc's should I shoot for? I've heard the banshee guys can sometimes go with 17cc domes, but that sounds pretty small for my bore- 67.25mm. I will be running VP V12 gas and I don't want anything too wild, but I deffinately want enough comp for it to require the race gas to run. So, any answers?

Also, my machinist says that he can put the heads on the lath and mill them for O-rings like the pro-design heads. My questions on this are- where can I get the o-rings, and will this be a cooling problem due to the fact that every chamber will be opened? With the gaskets, about half of the water jackets in the head are choked off by little openings in the gasket.
Thanks,
JP

 

Okay, DaBeechMan, where are you on this one?

 

depending on the porting, a 19cc is works nicely. although there are negative things u cant correct on the stock head. i would recommend getting a custom billet set up. the squish can not be corrected on a stock head without completely reconfigurating the dome.

 

Thank you very much trx250rjb. I understand the benifits of a billet head, but I have two reasons against them.
1. The gain you get vs. a properly milled stock head is allmost nonexistent so why pay the extra $$
2. When people look at my engine I want them to see stock components, you can probably guess why[img]i/expressions/face-icon-small-wink.gif[/img]

My machinest is pretty confident that he can get the chamber to my specs, so the only thing that is really still a problem, is the angle of the plug, and I'm not that concerned.

Thanks again,
JP

 

you are welcome, but a custom head dome built to your cylinder will make nice gains. i have gained over 2 bike lenghts with custom cut domes over generic pro designs.