317 heads
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From: Wilson n.c.
[QUOTE=G Atsma;20169442]Just to expand on the above, you will lose a tiny bit of compression due to 317 chambers being 1cc larger. Other than that no hassles.[/QUOT\
i was gonna get the 317 cnc ported and mill a bit to achieve 11.0-11.3 i also have the l92 head but i think the smaller runner would make better low end power
i was gonna get the 317 cnc ported and mill a bit to achieve 11.0-11.3 i also have the l92 head but i think the smaller runner would make better low end power
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From: Central Cal.
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There is some good info on porting the 317s with some flow numbers. Various stages etc, from a few minutes per port to full work. I was thinking 317 with the bigger ports, for a 4.00" stroker. My issue with the 317s is more with the chamber design rather than the volume. They are a great head, and the exhaust port flows really well.
I'm looking into using an L92 head with a good long tube intake to help with velocity.
The cathedrals may be better low end, but how much, and is it worth it? I'm leaning towards L92 at the moment, but I would still say in the fence for my application. 24ft 5000lb offshore boat. So cruise at 3500 rpm, and peak at 5800. BSFC is important to me, more than just raw power, and I can't just add rpm to the drives.
Cathedrals have good velocity for stock displacement. 408ci may maintain airspeed enough. Worth looking into.
I'm looking into using an L92 head with a good long tube intake to help with velocity.
The cathedrals may be better low end, but how much, and is it worth it? I'm leaning towards L92 at the moment, but I would still say in the fence for my application. 24ft 5000lb offshore boat. So cruise at 3500 rpm, and peak at 5800. BSFC is important to me, more than just raw power, and I can't just add rpm to the drives.
Cathedrals have good velocity for stock displacement. 408ci may maintain airspeed enough. Worth looking into.
