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RICHARD TILL · 03-01-2016

Roadster, I hope that you have forged pistons with deep valve reliefs. Small dome, flat or dished? I`m guessing cast. At about .570 lift on the cam and you`re in danger of valve to piston interference. On the 3917215 heads you`re your limited to about .550 lift before danger of retainer to guide clearance problems. Mill the guides down and machine them for positive seals. Need at least .060 clearance to be safe. Don`t worry about those heads not being able to breathe. It`s the same closed chamber head that was on the earlier 396`s & 427`s. The 489 i have with the Bullit .709/.709 roller has a set of oval port 781`s with 2.190/1.880 valves. Edelbrock with 1150 Dominator. MSD dist. and 6AL box. It runs 10.20 in the quarter @ 6300 rpm wot. With a three second 150 shot it`ll run a 9.70 @ 6700 rpm wot. A Fel-Pro 4.370 bore gasket compressed to .039 would be a good choice unless you could find a Victor tin metal gasket. In the early 70`s i would spray them with aluminum paint on both sides and apply asap. Hope i haven`t been a bother. Not trying to steal the post. Best of luck in retirement.

03-01-2016	#14
RICHARD TILL Join Date: Aug 2005 Location: Iuka, Mississippi 38852 Posts: 756	Re: The Time is Now...... Roadster, I hope that you have forged pistons with deep valve reliefs. Small dome, flat or dished? I`m guessing cast. At about .570 lift on the cam and you`re in danger of valve to piston interference. On the 3917215 heads you`re your limited to about .550 lift before danger of retainer to guide clearance problems. Mill the guides down and machine them for positive seals. Need at least .060 clearance to be safe. Don`t worry about those heads not being able to breathe. It`s the same closed chamber head that was on the earlier 396`s & 427`s. The 489 i have with the Bullit .709/.709 roller has a set of oval port 781`s with 2.190/1.880 valves. Edelbrock with 1150 Dominator. MSD dist. and 6AL box. It runs 10.20 in the quarter @ 6300 rpm wot. With a three second 150 shot it`ll run a 9.70 @ 6700 rpm wot. A Fel-Pro 4.370 bore gasket compressed to .039 would be a good choice unless you could find a Victor tin metal gasket. In the early 70`s i would spray them with aluminum paint on both sides and apply asap. Hope i haven`t been a bother. Not trying to steal the post. Best of luck in retirement.