A
Anonymous
Guest
Is there a way to determine ones static compression ratio after reassembling an engine (without know all the measurements)?
-Chris
-Chris
I have seen it done on a engine stand. but you have to tilt the engine to where the sparkplug hole is the highest point. Then comes the simple part.
CC it piston up valves closed. This is a very acurate way of doing it. Just remember you are not CC ing just the head but piston dome or dish, deck height, and head gasket too.
Jim
CC it piston up valves closed. This is a very acurate way of doing it. Just remember you are not CC ing just the head but piston dome or dish, deck height, and head gasket too.
Jim
THE EASY ANSWER IS:
If your engine has not been rebuilt before and it's a 1966 200 CID, it was about 9:1:1 when new, If you rebuilt it and did nothing to mill the head or deck the block and you used a new thick head gasket, then your compression is about 8:5:1 or somewhere near there!
If your engine has not been rebuilt before and it's a 1966 200 CID, it was about 9:1:1 when new, If you rebuilt it and did nothing to mill the head or deck the block and you used a new thick head gasket, then your compression is about 8:5:1 or somewhere near there!
A
Anonymous
Guest
Thanks guys but I think it going to be a little more complicated than doing some of the ideas suggested.
Take a look at this link. It will give you an idea as to where I am with my compression problems.
http://fordsix.com/forum/viewtopic.php?p=79266#79266
-Chris
Take a look at this link. It will give you an idea as to where I am with my compression problems.
http://fordsix.com/forum/viewtopic.php?p=79266#79266
-Chris
A
Anonymous
Guest
Stang';
When I first rebuilt my 200 (79 Fairmont, D8 head), I used the Victor gasket (.045" assembled) and the CR came out less than 7.8:1.
I milled the head .010" and switched to the steel gasket (.018" thick) to get it up from the original 8.0:1 (calculated) to 8.6:1. I can run the junkiest gas I can find with 10 degrees static advance (36 degrees total) with no ping.
The original head's chambers CC'd out at 60cc. After milling, they CC'd out at 58cc. If you mill (or already milled) too much, then the valves could end up hitting the pistons. My valves clear the pistons by about .060" after the .010" mill, and my deck height (average) was around .044".
When I first rebuilt my 200 (79 Fairmont, D8 head), I used the Victor gasket (.045" assembled) and the CR came out less than 7.8:1.
I milled the head .010" and switched to the steel gasket (.018" thick) to get it up from the original 8.0:1 (calculated) to 8.6:1. I can run the junkiest gas I can find with 10 degrees static advance (36 degrees total) with no ping.
The original head's chambers CC'd out at 60cc. After milling, they CC'd out at 58cc. If you mill (or already milled) too much, then the valves could end up hitting the pistons. My valves clear the pistons by about .060" after the .010" mill, and my deck height (average) was around .044".
A
Anonymous
Guest
Could a formula be derived using octane, ambient temp, operating temp, spark advance and ping threshold to arrive at compression ratio? Or are there too many other variables?
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