Is it possible to get the compression ratio by knowing the type of heads, pistons,and thickness of gasket? I am trying to get an idea if I can run pump gas 94 Oct. When I purchased the car it ran best on 110 Oct. without knocking.
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No- it will all be a guess. After 33 years and heaven-knows-how-many overhauls, all the components that determine compression ratio in a given engine may be changed, worn or remachined. You'll have to physically measure the ratio to be sure. Keep in mind, the engine doesn't know or care about the ratio; it only responds to compression pressure. So an engine at 11:1 with a radical cam may actually have a lower pumping pressure at startup than a 10:1 engine with a mild cam. Incidently, a compression gauge is not dependable for this type of test but pressures of 180-and-up psi during a compression test means there are seriously non-street-type parts in there. 110- octane racing fuel will make about any musclecar engine run good but most of us can't afford $6.25 a gallon on a regular basis.....
Cab-
This might give you a baseline.
I have run 4V, big-valve/big-port closed-chambered 'quench' heads measureing out at 62.4 cc with flat-topped pistons which 'the book' says will give +- 10.50 to 11.00. And running on our 95 octane pumpgas here with a mild Hyd. cam have encountered no problems at all. The 'quench' closed-chambered hds. do allow higher compression due to the cooling of the mixture as the flame front gets "quenched" travelling across the chamber & due to the more efficent burn of these heads. They are the way to go if u are looking for middle to top end use. But if u are looking at relatively 'normal' stoplite dragging, useing more bottom-end torque, then the smaller ports / valves of the 2V hds., with their higher velocity thru the narrower, smaller ports are the way to go I feel. IMHO.
This might give you a baseline.
I have run 4V, big-valve/big-port closed-chambered 'quench' heads measureing out at 62.4 cc with flat-topped pistons which 'the book' says will give +- 10.50 to 11.00. And running on our 95 octane pumpgas here with a mild Hyd. cam have encountered no problems at all. The 'quench' closed-chambered hds. do allow higher compression due to the cooling of the mixture as the flame front gets "quenched" travelling across the chamber & due to the more efficent burn of these heads. They are the way to go if u are looking for middle to top end use. But if u are looking at relatively 'normal' stoplite dragging, useing more bottom-end torque, then the smaller ports / valves of the 2V hds., with their higher velocity thru the narrower, smaller ports are the way to go I feel. IMHO.
CAB.
For more info. on compression, see post of KORINA's on page 3 under COMPRESSION RATIO.
For more info. on compression, see post of KORINA's on page 3 under COMPRESSION RATIO.