945.0
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i have 64cc heads want to bring the compression up to 10:1 how do i pick the right piston.
pistons and compression
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justinschmidt1
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945.0
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i dont know the comp. gasket, or piston to deck clearance
That info is in the component you want to use. Summit/Jegs used to have a calculator in their piston selection area that had those variables as well.
Piston manufacturer will give the deck and volume. Stock deck, I just used 0 because the piston is flat with the block. It is on a lot of domed pistons as well. Gasket manufacturer should give the #s for the gasket info.
Why is 10.5 the majic #? Didn't you sell, or were gonna sell your car?
Piston manufacturer will give the deck and volume. Stock deck, I just used 0 because the piston is flat with the block. It is on a lot of domed pistons as well. Gasket manufacturer should give the #s for the gasket info.
Why is 10.5 the majic #? Didn't you sell, or were gonna sell your car?
cantbuytime
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You need to know every detail to get an accurate compression ratio calculation.
Saying the piston is at 0 deck when its actually .010+ in the hole, will make a noticeable difference in the ratio. IMO
Most stock unmachined 302's are .010 to .015 in the hole
Mine is .007 in the hole after it was decked .005
U need to get a dial gauge and check it. Worth the $25 for the tool, it will also come in handy to degree the cam.. HF tools is where I got mine.
head gasket (Fel-Pro) are usually .040 to .042 thick when compressed.
Saying the piston is at 0 deck when its actually .010+ in the hole, will make a noticeable difference in the ratio. IMO
Most stock unmachined 302's are .010 to .015 in the hole
Mine is .007 in the hole after it was decked .005
U need to get a dial gauge and check it. Worth the $25 for the tool, it will also come in handy to degree the cam.. HF tools is where I got mine.
head gasket (Fel-Pro) are usually .040 to .042 thick when compressed.
^-- that's the data i used
MustangChris
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is decking the heads an option on your set up? might not bumpy ya up to 10.1, but it may be a mo' cheepa option if you just want to bump comp. until you can buy a blower or something.....
... just throwing some spit into the salad...
good post cantbuytime, BTW. lol.
... just throwing some spit into the salad...
good post cantbuytime, BTW. lol.
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945.0
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the heads are brand new and i dont want to mill them. my plans are 10:1 compression with a nice turbo setup with big injectors and well im sure you get the point. but as for now i am stripping the block having the black baked and blasted and honed, crank polished (grinded if needed) forged flattop pistons, forged rods, canton main girdle and oil pan. im setting up the motor first then going to work into the turbo.
richv- no i was never selling my car. i was selling some parts off of it.
mustangchris- you like spitting on salad lol
richv- no i was never selling my car. i was selling some parts off of it.
mustangchris- you like spitting on salad lol
MustangChris
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gotcha... i wouldnt want to mill brand new heads either. lol.
and salad is always better with secret sauce and some spit.
and salad is always better with secret sauce and some spit.
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945.0
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that little extra goes a long way!!! im planning on have the motor running first then slap a nasty turbo on it.
MustangChris
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very nice. :-D
cantbuytime
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What heads are you using? You can get them to assemble the block and check the piston to deck.. Then have them mill the deck to get it close to zero.. I like to stay within .003 to .004 from being flush. Helps if you ever have to mill the deck, then there is still meat to do it.
You will need a dome piston to get over 10:1 with 64cc heads.. Or zero deck the block, run .020 thick headgaskets with flat tops and you will likely still be at a 9 something compression. It will probably need dome pistons..
Anything over 10:1 is not necessary if your going to run alot of boost. Motor would probably live longer with a lower compression.
You will need a dome piston to get over 10:1 with 64cc heads.. Or zero deck the block, run .020 thick headgaskets with flat tops and you will likely still be at a 9 something compression. It will probably need dome pistons..
Anything over 10:1 is not necessary if your going to run alot of boost. Motor would probably live longer with a lower compression.
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945.0
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thats why i am going to stick with 9.5-10:1 compression. keeping stock bore and stroke. but changing to forged rods, pistons. i did get called out earlier on another forum. the girl has a 98 z28 her and her husband bought the car with 180k miles stock motor for 7k bucks outrageously overpriced. anyway her hubby has been putting all the money into it spent all the tax money they had just to make it faster, the funny thing is that they live at home with her mom have a kid and she just started working, and yet she was *****ing at me and my wife to sell the stang to provide for our kids. what a joke i live on my own, and pay for everything myself, my wife is a stay at home mom and is going to school for medical degree. she had the nerve to say how long do i have to wait till yours is finished. i will post a vid if i can find it of the z28
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945.0
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http://www.youtube.com/watch?v=1w_4NPZ1fww what do you think has been done to the motor. sounds like lopy cam to me car originally ran a high 12 with slicks and aftermarket intake
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