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looking for some advice

William Carter
I love my Chevy Chevette!
Posts: 4
Joined: 03/14
Posted: 03/12/14 03:21 PM

I am building a 1980 Chevy 350 4 bolt main  have it bored out 60 over and turned the crank to a 10/10 and running a 288/298 cam with a set of 882 heads was wondering what my compression should be and aproxamitly how much HP it should make as the is the first motor I've built this big  

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V-6 Camaros rule!
Posts: 90
Joined: 11/13
Posted: 03/12/14 05:02 PM

compression ratio depends on piston dome or dish shape???

since you are running stock sized combustion chambers.. the only variables will be if you decked the block.. how much was surfaced off the heads..  piston selection and head gasket thickness..

here is a compression ratio calculator..

as i recall the 882 heads are 76 cc..

you are probably going to be far better off with a pair of Vortec heads that have been modified for the increased valve lift that won't smash the seals..

here is an article on them and the mods needed...

do me a favor.. please use some hylomar on the head gaskets..  a proper 192F thermostat.. a cooling system bypass so there is a constant flow from behind the thermostat back into either the water pump or into the same side of the radiator tank where the lower hose hooks to.. so there is constant coolant circulation around the cylinders up thru the back of the heads.. forward thru the head again and again until the thermostat opens.. this allows the engine cooling system to operate as designed.. and will reduce the chances of overheating the engine at +060 bores.. you may also want to spend the extra funds for a sonic test of the cylinder walls at that bore size.. so you don't end up putting parts in against paper thin cylinders..

does not matter that this article is on a mopar.. cast iron is cast iron..  

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