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L98 Alum. heads...what headgaskets?

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Old 02-11-2006, 01:28 PM
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L98 Alum. heads...what headgaskets?

I have a pair of aluminum heads off of a corvette and i was wondering if i can use a steel shim for headgaskets or do i have to use the factory head gaskets? and i am wondering what head bolts i can use? can i use my cast iron head bolts or do i have to buy new ones? i know with most alum head applications they recomend you buying new headbolts but i like to know what the story is.
Old 02-12-2006, 01:51 PM
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anyone?
Old 02-12-2006, 01:56 PM
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Not sure about the head gaskets, but you should use new head bolts with the machined flat washers needed for aluminum heads.
Old 02-12-2006, 02:01 PM
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yeah i used arp head bolts w/ washers with my edelbrock rpm heads...... and i used stock headgaskets for a regular cast iron head SBC
Old 02-12-2006, 02:09 PM
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A thin steel shim head gasket can be used with a aluminum head but you may get some galvanatic action ( corrosion) between the head and block because of the electrolitic action of the disssimular metals. It takes a long time for this corrosion to happen. Same as the water port openings will corrode over time on a aluminum manifold and steel heads.
using good antifreeze with corrosion additives or some "Water Wetter" in the cooling system will help a lot too.
If you're going to use a thicker composite gasket get on designed to not "brinnell" the aluminum head surface. (indent the head) (softer preflattened copper fire ring).

Reguardless of which gasket retorque the head bolts after a few warm up cycles. the head bolts will need hardened washers under the heads of each bolt.

Last edited by F-BIRD'88; 02-12-2006 at 02:12 PM.
Old 02-12-2006, 02:14 PM
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Use the stock GM .038 gasket or the performance GM .028 gasket to boost compression.
Old 02-13-2006, 11:11 AM
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aluminum expands more than steel does when it gets hot, but then it cools faster than steel does. You'll be getting a lot of shearing of the gasket. it's best to use a standard OEM style FelPro gasket. You could try your luck with a steel shim gasket but as mentioned about the galvanic action, you might get rust that glues the head to the block
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