how much compression does my motor have?

stanger8172 · 03-06-2002, 01:45 PM

An old buddy of mine built my engine and he said I have 10:5:1 for compression but he wasn't sure. As you should see in my sig my stock heads are milled .030 and I am using the stock pistons. What's my compression at?

PKRWUD · 03-06-2002, 02:28 PM

If the only change made was to shave .030" from the stock heads, then your real compression ratio is approximately 9.3:1, depending on the head. It could be as high as 9.5:1, but 9.3:1 is more likely.

Take care,
-Chris

stanger8172 · 03-06-2002, 10:36 PM

Thanks, Brian

03-06-2002, 01:45 PM	#1
stanger8172 Registered Member Join Date: Nov 2000 Location: Milwaukee,Wisconsin Posts: 380	how much compression does my motor have? An old buddy of mine built my engine and he said I have 10:5:1 for compression but he wasn't sure. As you should see in my sig my stock heads are milled .030 and I am using the stock pistons. What's my compression at? __________________ '91 LX convertible , T-5, Centerforce Dual Friction, MSD Blaster Coil, FR 9MM wires, 13* timing, 1.6rr, ported/polished/milled stock heads, 1.94/1.60 stainless valves, March Performance Pulleys, K&N panel, 1"spacer, BBK shorties, 2 1/2" off road H, Summit 2 1/2" catback

03-06-2002, 02:28 PM	#2
PKRWUD Junior Member Join Date: Mar 1999 Location: Ventura, California Posts: 8,981	If the only change made was to shave .030" from the stock heads, then your real compression ratio is approximately 9.3:1, depending on the head. It could be as high as 9.5:1, but 9.3:1 is more likely. Take care, -Chris __________________ Webmaster: Rice Haters Club Jim Porter Racing Peckerwoods Pit Stop Support Your Local RED & WHITE!

03-06-2002, 10:36 PM	#3
stanger8172 Registered Member Join Date: Nov 2000 Location: Milwaukee,Wisconsin Posts: 380	Thanks, Brian __________________ '91 LX convertible , T-5, Centerforce Dual Friction, MSD Blaster Coil, FR 9MM wires, 13* timing, 1.6rr, ported/polished/milled stock heads, 1.94/1.60 stainless valves, March Performance Pulleys, K&N panel, 1"spacer, BBK shorties, 2 1/2" off road H, Summit 2 1/2" catback

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