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having your head milled? how/who/where?


oneday

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a ? for everyone. does any one in detroit area know where someone might go to have there head milled? also how much milling = how much compression?

thanks, new member ONEDAY. :D

I shaved 30 thou of my stock head which then produced 170 psi of compression. This is too much to be cooled be the stock cooling system! It blew my top-end banghead Here is a quote from the "Vito's Performance" site:

 

"You can assume that your power output will increase 2 horsepower for every 10 psi you raise your cranking pressure. unless you drag race only for 300 ft or less we do not recommend you go past 170 psi it will build heat that cant be dissipated with the stock cooling system without a cool down rest. We get reports that people run smaller sizes than what is recommended above for the specific octane used and you may very well do it for awhile but from our experiences detonation will eventually rear its ugly head and bite the buddy you loaned your bike to."

 

I'm buying a cool head of some sort when I rebuild my topend to be on the safe side. But I do have a stock shaved head for sale :lol:

 

Cya

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a ? for everyone.  does any one in detroit area know where someone might go to have there head milled?  also how much milling = how much compression?

thanks,  new member ONEDAY. :D

I shaved 30 thou of my stock head which then produced 170 psi of compression. This is too much to be cooled be the stock cooling system! It blew my top-end banghead Here is a quote from the "Vito's Performance" site:

 

"You can assume that your power output will increase 2 horsepower for every 10 psi you raise your cranking pressure. unless you drag race only for 300 ft or less we do not recommend you go past 170 psi it will build heat that cant be dissipated with the stock cooling system without a cool down rest. We get reports that people run smaller sizes than what is recommended above for the specific octane used and you may very well do it for awhile but from our experiences detonation will eventually rear its ugly head and bite the buddy you loaned your bike to."

 

I'm buying a cool head of some sort when I rebuild my topend to be on the safe side. But I do have a stock shaved head for sale :lol:

 

Cya

I had mine milled 0.030" at a local machine shop and my compression went from 120 to 154 psi. Are you sure that yours hadn't been milled before? What was your compression before you had your head milled. 170 psi sounds like a lot.

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"You can assume that your power output will increase 2 horsepower for every 10 psi you raise your cranking pressure. unless you drag race only for 300 ft or less we do not recommend you go past 170 psi it will build heat that cant be dissipated with the stock cooling system without a cool down rest. We get reports that people run smaller sizes than what is recommended above for the specific octane used and you may very well do it for awhile but from our experiences detonation will eventually rear its ugly head and bite the buddy you loaned your bike to."

 

I'm assuming that a good aftermarket head must be the makes of a better cooling system. I'm running 192 and it's fine on the mx track.

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You won't need to mill your head if it's a cool head. They have interchangeable domes. The pro flow impeller will do wonders to the cooling efficiancy of the motor along with stripping the paint off the radiator and straightening out EVERY bent colling fin.

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Sounds like they did not re-cut the squish band, after you mill the head you must cut the squish for the desired cc. If you want to talk to someone about milling heads properly 541-942-1166 ask for dave (its a performance atv shop) He has milled heads, bored cylinders, re-sleeved, and ported for years (old school dude) He is in oregon but he will cut your head and send it to you. His machine work is impressive!

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I have a Trinity modified stock head with 20cc chambers and swirl cuts in them. It produces 150-160 psi. Perfect for pump gas. Gives a good boost in grunt and response. Never had a problem with overheating and I trail ride. I've got two of them identical, you interested in one let me know.

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