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Discussion Starter #1
ive been considering shaving/resurfacing the head to lower CC and raise C/R.
1) is it worth the money?
2) how much can i shave before it becomes a interference engine w/ stock cams?
3) if i plan to get stage2 cams later on is this a good idea? or how much should i shave off if i plan on getting stage2 cams?
 

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Yes it will help , compression is the #1 factor in gaining HP , you can surface the head a lot , use stg3 cams and still be fine , I would go back with ARP head studs and do the cams at the same time you do the head , a tune will be required

Tom
 

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Discussion Starter #3
I have not looked into how much machining costs but if I can get a resurface for relatively cheap I'd gun for it. Cams however are not cheap for me at all. I'm willing to do the work 1 piece at a time, even if its required to pull apart and put back together. Plus I'd grab a head from the scrap yard.



Is a tune required for resurface?
 

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Question #2 is unanswerable as every engine has different tolerances, even the degreeing in of the cams (overlap) will affect the space there.
 

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Discussion Starter #5
Well if I rephrase that to what should I reshave the head to w/ stock cams? What's your opinion?
 

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Thats What She Said
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10 to 15 mil is a safe bet. while you should still check for interference on this level of shaving the head anything over 20 from my research starts to require more attention and would not go over 30 mil. (30 mil = 0.030")
 

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Mil is in inches... as stated 30 mil = 0.030" 30mm is a little over an inch.
 

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Discussion Starter #9
i was gonna say damn, lotta cutting XD
so 15 mil is a good place to be? how do i figure c/r?
 

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Thats What She Said
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C-F-M.com under the omnetics head gasket has a ok calculator that can be used.

The more experienced builders will have to tell me if I am wrong, but the best way is to use a syringe with a fluid that can do a controlled application of the cc of the fluid. Find the volume in the head before the work and then perform the test again after the work is done. then just subtract that from factory spec of your cc of the motor and then do the res of the calculations.
 

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IIRC the zetec head can be shaved somewhere around 0.110". But it's not recommended to go deeper than 0.080" for a street car.
 

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Discussion Starter #13
.08"? is there a specific reason for that or just clearance issues?
 

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0.080" is a fairly aggressive shave...

if you did not ask for it usually its due to aluminum heads and heat issues that cause the head to get out of square.

why was your head off and at the machine shop? overheating is the likely cause for needing that much shaved to get it true again.
 

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Its a race car. I took the head to get a valve job and said "maybe shave the head too." When i picked it up he said i shaved it to give you some more performance and i left it at that.
 

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Yeah....im new to fuel injected engines. Im used to just throwing parts at small blocks. I didnt know about tuning the computer and spent all my money on parts and machine shop.

I also have a bbk throttle body, msd coil and wires, underdrive crank pulley, comp cams severe street/competition cams with CFM adjustables, 27lbs fuel injectors and pacesetter header. I have an SVT header just cant afford a new exhaust right now.

The head is also port and polished with a 3 angle valve job and a .51 cometic head gasket.
 

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Not tuning with the mods. would be like not doing jetting/timing for your mods with the small block - wouldn't run well or last long.
 
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