cnc d heads
#31
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This is the 4th time I am changing the heads on my boat have some good dyno time. The sr20 the port volume is to big the low end and mid range would be gone or I would of bought them but ended up going with the big duke sweet 16*.
BB2+ boat plenty of power to plane off than I went to a 351 oval port boat would plane off ok. Put the 383HH on it would not plane off on calm water. But the power went up may be 40 or so. Think sr20 is 440cc and the big dukes is 415 but the runner is longer.
Shooting for 1050-1075 but it will be on 100LL aviation gas.
BB2+ boat plenty of power to plane off than I went to a 351 oval port boat would plane off ok. Put the 383HH on it would not plane off on calm water. But the power went up may be 40 or so. Think sr20 is 440cc and the big dukes is 415 but the runner is longer.
Shooting for 1050-1075 but it will be on 100LL aviation gas.
#32
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#33
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#35
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#36
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Not sure of the hours I have put on them. Valve train on old motors had 2.4 stainless valves it would tare up the intake lift ramps on camshaft. New builds are getting Titanium intake valves that have the Crn coating so camshaft will live and going with the .937 lifters and 55MM camshaft. My biggest problem is if you have a leaky header and don't know about it ****s stuff up.
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#38
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Not sure of the hours I have put on them. Valve train on old motors had 2.4 stainless valves it would tare up the intake lift ramps on camshaft. New builds are getting Titanium intake valves that have the Crn coating so camshaft will live and going with the .937 lifters and 55MM camshaft. My biggest problem is if you have a leaky header and don't know about it ****s stuff up.
#39
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Yes the upgrade I am doing is going to fix all problems. I would of run a stainless intake valve but the weight is a killer on that size valve. 2.450 6.700 long.
What kind of valve springs you running and how much lift?
What kind of valve springs you running and how much lift?
#40
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I think Titanium intake is the way to go. Springs will last longer, guides, lifters ect. Ect. The motor will rev a lot faster I'm just guessing at this number but I bet you save around 3lbs going to a titanium valve. That's what I would use with my new setup if I had the xtra money. I still may we will see.