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Old 01-19-2024, 05:29 PM
skinny035 skinny035 is offline
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Default 389 tri-power recipe?

I am building a 389 for my 65 GTO and would like some advice. I have a restored 65 Tri-power I'm using. I will bore .018 over to 4.080. I can use the 068 cam and want it to be between 360-400 HP on pump gas. Please give me recommendations on the heads, etc. It will be a stock crank.

Tom

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Old 01-20-2024, 03:05 PM
steve25's Avatar
steve25 steve25 is offline
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If you want to get to 400 hp with iron heads then build the motor with pistons to work with the 67 and later heads with there 14 degree valve inclination angle.

This opens the door to the aftermarket heads to allow you to top 400 Hp if you care to.

With the 068 cam and stock iron heads heads you will be right in that 360 hp power range with a 9.5 comp.

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