Has Anyone Tried a M.M. Billet Head ??

Well more surface area = better cooling.
Allthough i think it would be a minor increase in cooling efficcency.
You could shot pene it and that would be the best.

I think the 2 most critical aspects are.

#1 most important.....The total combined surface area of the fins and head.

#2 also important .....the direction of the fins and the impact of the airflow due to the fin direction.

#3 SPARKPLUG.

The sparkplug Heat Range is actually the rating of how quickly the sparkplug removes heat from the engine.
 
I thought about shot-blasting. Probably best, but I think that a stiff stainless-steel wire brush in an electric drill would help cooling.
(My RSE hi-comp billet head runs a bit hot too. Not too bad, but it needs more than a cooler plug. That only goes so far.)
 
I know what your saying.

You know the head runs too hot when......

Your sparkplug shows good color and not running too lean.

Your engine runs great at first really fast and powerful.

But after a 2 or 3 mile WOT it starts to loose power and bog down.

Also you will hear a rattling noise that sounds like you got BB's in the cylinder.
 
Mine's nowhere near that bad, but it does run a bit hot.
The idle reduces as it heats up, if that's relevant. After a couple of miles hard riding, I need to adjust the idle up a bit.
 
I probably will help if you get something like a 40 grit sand paper and sand it all so it has mini colling fins(like a porous sand cast)
And Andrew that what i have done lots and lots of times with my heads. Piece of glass+sand paper+gentle 8 figure sanding=perfectly flat head:rolleyes:

G-Superior:D
 
Yep. I also considered 36 or 40 paper. In fact, almost anything that can roughen up the surface sufficiently. Fine, closely spaced knife grooves etc. It won't just increase surface area but also increase turbulence, providing even more cooling, I would think.
(This wouldn't be useful on a stock head - they run at a good temp.)
 
ok so i have the original ce hi comp head and yes the compression is too much for pump fuel causing detonation and scorching pistons yes i agree but it was a prototype rich thats what prototypes are for i had no issue with the head because i run only race fuel and have easy access to it i run about 106 to 108 blend of vp i mix 3 gallons of ms103 oxygenated which is 99octane and 1 gallon of q16 oxygenated with lead the ms is unleaded. so needless to say that head works for me and def gives me a good power increase and i cant say i have or ever will do a 3 mile wot run either. the hottest the head has ever gotten is 300 which is toatally fine for an air cooled engine considering my jd's at work run 450degrees the new head has lower compression than the prototype head and is made to run with 93octane with a b8s plug i have that head on a bike and run the same blend of fuel with the max temp of 280 to 300 and have the same performance maybee a bit less but not much
 
Ok thats good.
However the puch head has a 5cc combustion chamber making it 2 cc's less than the billet head and much higher compression.
The puch chamber is centralized and about the size of a quarter to resist the pinging.
I am running a NGKB9HS PLUG and i am having no issues with fouling and the engine is running cool enough.

I do like the billet head i just think it needs more fins.
 
The sparkplug Heat Range is actually the rating of how quickly the sparkplug removes heat from the engine.

This is something new to me. I was always taught that the heat range of a plug meant that the electrode maintained heat better to resist fouling and better combustion. I never knew that it had anything to do removing heat from an engine. Thanks for bringing this up.
 
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