Compression and Hp guess on my build

67440chrg

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I am mainly wondering about how much comp my 440 will have. If anyone has a good guess on Hp thats ok too.
1974 440 .030 over bore.
stock stroke
L2266 TRW .030 pistons around .091 down
84cc Edelbrock 60929 rpm heads out of the box
Lunati Voodoo 276/284 adv 234/242 @.50 Duration 513/533 lift LSA/ISL 110/106
Torker II intake
750 Double pumper
17/8 primary 3' collector headers 2.5 H pipe with turn downs at mufflers
MSD 6a ignition & Dist
727 rev pat man shift 2800 stall
355 sure grip
3800 lb b body

My car had about 4000 miles on its previous build and had a couple lifters making noise so I figured I would remove the 516 heads and up size the cam. I know porting and a duel plain intake will help but I have spent all I can for now and have what I have listed. Will it make much difference to go with a steal shim Mopar head gasket over the Felpro 8519 pt1s I already have.
Thanks in advance.
 

Mopars & Missiles

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I think you are going to be disappointed with this combination. Quick calculation shows you will be around 8.5 to 8.8/1 at best. With aluminum heads, you want around 10.5/1 to run 93 octane pump gas on the street.

The big problem is the 0.091 pistons down in the hole.

Using the 0.019" steel shim head gasket instead of the 0.039" Felpro's will give you about 3/10ths more compression. (8.8 to 9.1/1) Still not enough.
 

Meep-Meep

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If all you can get out of that is about 9:1 CR then I'd go smaller on the cam and use one ground on a 112-114 LSA.
 

IQ52

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It'll run great just like you have it. 400-420 HP and it'll pound you back into the seat. I wouldn't change a thing right now!
 

Banzaiii67

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Using the 0.019" steel shim head gasket instead of the 0.039" Felpro's will give you about 3/10ths more compression. (8.8 to 9.1/1) Still not enough.

Two like metals creates Galvanic Corrosion. Someone probably has ran steel shim gaskets on aluminum heads, but if it were up to me I wouldn't do it especially for that small of increase in compression.
 

67440chrg

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Thanks for the replies. I guess the 516s I had on it had more work no them than I first thought. I do know it would have a little preignition knock with 87 oct gas before.they had stainless valves, double springs & the intake had the bolt holes longated and it was a real pain to start all the bolts. I may down size the cam if summit will let me exchange it.I guess getting at least close to 500 hp aint going to happen with only 9:1 comp. I do have harland sharp roller rockers to switch over to the aluminum heads. Thanks again have a good christmas.
 

Cranky

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Two like metals creates Galvanic Corrosion. Someone probably has ran steel shim gaskets on aluminum heads, but if it were up to me I wouldn't do it especially for that small of increase in compression.
The main problem with using steel shim gaskets with aluminum heads is they alloy head expand at a different rate than the cast iron block does and the steel gaskets will etch into the aluminum over time.

- - - Updated - - -

Thanks for the replies. I guess the 516s I had on it had more work no them than I first thought. I do know it would have a little preignition knock with 87 oct gas before.they had stainless valves, double springs & the intake had the bolt holes longated and it was a real pain to start all the bolts. I may down size the cam if summit will let me exchange it.I guess getting at least close to 500 hp aint going to happen with only 9:1 comp. I do have harland sharp roller rockers to switch over to the aluminum heads. Thanks again have a good christmas.
The main reason low compression engines ping is because of the lazy flame front....and the fact there's none to very little squish/quench to help gets things moving. There's a lot of info on the web that addresses what's going on when you have a good quench distance. Low compression engines can and do run good if you cam them right and build a good combination but an engine with good a quench distance always run better. I also posted a thread some time back called 'quench explained' if you want to search for it. It's one of the few articles that helps explain it where most of us could more easily understand what's happening inside the combustion chamber.
 

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