Compression and Piston to Valve questions
01-15-2003, 11:30 AM
#1
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Compression and Piston to Valve questions can someone tell me what compression
30 thousand off is
35
40
45
50
55
I dont have the #'s and im too lazy to grad my calcuator...
Or better yet what does it take to get a stock head to 11-1?
Im in a situation where id like to not have to fly cut the pistons, since it isnt cheap to pull the motor apart.
I have 2.08 1.60 valves with a 226 234 55x 57x cam
id like to go bigger on the intake and smaller on the exhaust... i see a lot of guys with 228 224's and such but i dont know what compression they are running and if they had to clearence anything
30 thousand off is
35
40
45
50
55
I dont have the #'s and im too lazy to grad my calcuator...
Or better yet what does it take to get a stock head to 11-1?
Im in a situation where id like to not have to fly cut the pistons, since it isnt cheap to pull the motor apart.
I have 2.08 1.60 valves with a 226 234 55x 57x cam
id like to go bigger on the intake and smaller on the exhaust... i see a lot of guys with 228 224's and such but i dont know what compression they are running and if they had to clearence anything
01-15-2003, 11:43 AM
#2
Re: Compression and Piston to Valve questions Here is a quick rule of thumb.
30 off and bigger valves knocks your compression chamber CC to ~63.
For every 10 more off, it equates to about 1 CC.
Here are some compressions for stock bore stroke and a .052 gasket.
30 off = 10.9:1
40 off = 11.0:1
50 off = 11.2:1
55 off = 11.3:1
30 off and bigger valves knocks your compression chamber CC to ~63.
For every 10 more off, it equates to about 1 CC.
Here are some compressions for stock bore stroke and a .052 gasket.
30 off = 10.9:1
40 off = 11.0:1
50 off = 11.2:1
55 off = 11.3:1