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Old Oct 26, 2015 | 09:05 PM
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Default Heads

How much more hp can you get when you switch out ls1 heads for ls7 heads?
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Old Oct 27, 2015 | 12:56 PM
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It only works on 4.8ls swapped into Miatas, then you have to use the stock truck exhaust manifold and no bigger than 2" exhaust.
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Old Oct 27, 2015 | 09:02 PM
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On what shortblock?

Ls7 heads need more bore than the ls1 has.
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Old Oct 27, 2015 | 10:02 PM
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Originally Posted by kresseguie
How much more hp can you get when you switch out ls1 heads for ls7 heads?
About 150 HP to the wheels......give or take.

Give it a shot and get back with us, on that....

KW
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Old Oct 28, 2015 | 09:48 AM
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I think it's more like 150 per side
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Old Oct 28, 2015 | 10:11 AM
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Originally Posted by gnx7
I think it's more like 150 per side
Sorry.....my bad

KW
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Old Oct 29, 2015 | 04:26 AM
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KW, you were right, it's 150hp. You get to 150 hp per side when you use the small bore to large bore adapter plates. LOL
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Old Oct 29, 2015 | 09:37 AM
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The warranty on those adapter plates are only valid if you have those little fans in the cold air intake tube and a fart-can hon-duh exhaust.
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Old Oct 29, 2015 | 11:55 AM
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What if you notched the valves to clear the bore?
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Old Oct 29, 2015 | 03:02 PM
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Honestly, this is a joke. They don't fit. And for the price of ls7 heads, you can get aftermarket heads that actually fit the application. Ls7 heads can barely be made to fit the ls3 bore, and even that requires a smaller exhaust valve most of the time.

Can we please just let this abomination of a thread sink to the bottom and die?
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