so as iv posted before im building a 1984 460 and i am planning on using early c9ve heads and a performer plus cam and stock pistons. Can anyone first tell me what kind of compression ratio i would be looking at if i went with a .048 head gasket?

Also someone told me i should deck the block if im gonna run this setup because of dentonation issues. Can anyone explain what all this means? i know your shaving so much off the top of the block but wouldn't that increase compression?

i need this thing to run off pump gas so im trying to keep the CR as low as possible without sacrificing power

I have torn apart engines before but never built one up so your help is very much appreciated!!!

 

460ford.com

 

No matter what pistons they should be close to or zero decked & yes it does increase compression but it must be done if detonation is to be avoided. It is checked by mocking up the crank, rod and pistons in the block. You should check 2 on each bank, front and rear. Check the difference between the top of the piston and the top of the blocks deck with a dial gauge then mill the block accordingly. You will need to get your blocks align bore checked and the cylinders bored and honed first because you have to have your piston in the cylinder to check it's deck height, this is means another trip to the machine shop after you figure out how much needs to be removed. Stock 460 pistons can be as much as .040 in the hole if not more and that is a bad thing for any motor.
When you say "run off pump gas" do you mean cheep crap 87, or premium pump gas ?

 

Im talkin premium

 

I wouldn't want to go anymore than 9.5 to one with an iron headed motor on premium pump gas. You need to decide on how you want to get there. High comp head & low comp piston or low comp head & high comp piston. How you get there is always debatable.

 

the 460 forum here or 460ford.com if you aren't able to find what you need here

 

I'm running C9VE heads on on D1VE block. I'm running stock style replacement .030 pistons and had the blocked sqare decked from 10.322 (1971 and up spec) down to 10.300 (1968-1970 spec). This gets the pistons up to ZERO deck. Through the calculators I ran I came up with right at 10 to 1 compression, maybe slightly under like 9.9:1. My cam is .545 lift with 220 & 228 duration at .050. I've also got a Edelbrock Performer RPM air gap and other supporting parts. Runs great, no detonation.