Aluminum vs cast iron heads
09-03-2010, 05:31 AM
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Aluminum vs cast iron heads
Hey guys, I am considering buying these http://www.summitracing.com/parts/TFS-30300005/
But I have a few questions.. I am running a 78 350, 2 bolt block, with flat-top 4 eyebrow pistons..
When I did my calculations for compression with a 58cc block, I had somewhere along the lines of 12:1 compression..
What I've been reading about the aluminum is that an engine with cast iron heads with 10:1 compression burning 92 octane.. That if you were to switch them to aluminum it would run like it 9:1 compression.. Is this true?
But I have a few questions.. I am running a 78 350, 2 bolt block, with flat-top 4 eyebrow pistons..
When I did my calculations for compression with a 58cc block, I had somewhere along the lines of 12:1 compression..
What I've been reading about the aluminum is that an engine with cast iron heads with 10:1 compression burning 92 octane.. That if you were to switch them to aluminum it would run like it 9:1 compression.. Is this true?
09-03-2010, 06:23 AM
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Re: Aluminum vs cast iron heads
It's the chamber size that affects the calculations.
09-03-2010, 07:18 AM
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Re: Aluminum vs cast iron heads
You can get away with alittle more compression using aluminum heads rather then the Iron heads, for street car running 93 octane i wouldnt go past 11:1.
09-03-2010, 10:08 AM
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Re: Aluminum vs cast iron heads
An aluminum head transfers heat from the combustion chamber more quickly than iron, so you need to build the engine with a little more static compression to keep the output equal.
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