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1971 Corvette LS5 heads/intake

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Old Dec 4, 2017 | 07:25 AM
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Default 1971 Corvette LS5 heads/intake

What heads were on 1971 LS5 corvette, oval or square port?

Ted
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Old Dec 4, 2017 | 07:37 AM
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Hi Ted,
LS-5.
3993820= 1971, oval port, open chamber, 113cc chamber.
Regards,
Alan

Last edited by Alan 71; Dec 4, 2017 at 11:17 AM.
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Old Dec 4, 2017 | 07:53 AM
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Default 1971 Corvette LS5

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good morning
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Old Dec 4, 2017 | 10:40 AM
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Originally Posted by Alan 71
Hi Ted,
3993820= 1971, oval port, open chamber, 113cc chamber.
Regards,
Alan

I have always heard the LS5 with its 425 hp rating got the rectangular ports and the LS6 with its 365 hp rating got the oval ports. Am I confused?
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Old Dec 4, 2017 | 10:52 AM
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Backwards. Funny thing, 365 mercruiser is basically a 71 LS-6 with a marine cam.
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Old Dec 4, 2017 | 05:19 PM
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Default 454 LS5 or LS6

Originally Posted by NeverTooOld
I have always heard the LS5 with its 425 hp rating got the rectangular ports and the LS6 with its 365 hp rating got the oval ports. Am I confused?
LS6 425 hp
LS5 365 hp

Ted
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Old Dec 4, 2017 | 06:16 PM
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Those heads are "oval's" and they work really well when done correctly!

If you're planning on building your LS-5 you can get above 500 HP @ 5500, and 550# Torque @ 3900/4000 with 9.5:1, with ALL the factory external components, including the Q-jet carb!

Thanks, Gary in N.Y.

P.S. On the heads we use SBC (11/32") intake valves and Mopar (11/32") exhaust valves. Fully rollered (retro-hyd) platform and 100% stock-appearing, down to the "single-thick" valve cover gaskets!
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