Supercharged 540 Camshaft
#1
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I need some help from you who know this stuff. I searched and know I would probably just go with a 741 cam for a naturally aspirated 540, but I couldn't find much for a blown engine.
so here is what I am working on. I just bought a 22 Eliminator Daytona, only took the boat out once before weather changed, It has a bravo one and 136 gears. The guy I bought it from said it turns a 30 Bravo 1 prop at 5300 rpm. I had a 24 Bravo one on it when I took it out. It planed out so easy and would stay on plane at 2200 rpm. I found out the new engine had problems, cylinder bottoms were left sharp and I now have some wonderful scratches in the cylinders bottom to top and leaks down at 15%. I decided to start over. I am building a 540 and using the 420 mega blower it had on the old engine. I have the cast iron Merlin 320 heads. ( I can use different ones if needed). It also has lightning headers. I would like to keep max rpm at 5500. I didn't try the 30 prop, honestly the boat scares me. lol I don't need a 100 mph boat. I am more concerned about blowing fuel out the exhaust. I figure I will be running around 6-6.5 lbs boost. If you guy's can give me your thoughts it would be most appreciated. Thanks
so here is what I am working on. I just bought a 22 Eliminator Daytona, only took the boat out once before weather changed, It has a bravo one and 136 gears. The guy I bought it from said it turns a 30 Bravo 1 prop at 5300 rpm. I had a 24 Bravo one on it when I took it out. It planed out so easy and would stay on plane at 2200 rpm. I found out the new engine had problems, cylinder bottoms were left sharp and I now have some wonderful scratches in the cylinders bottom to top and leaks down at 15%. I decided to start over. I am building a 540 and using the 420 mega blower it had on the old engine. I have the cast iron Merlin 320 heads. ( I can use different ones if needed). It also has lightning headers. I would like to keep max rpm at 5500. I didn't try the 30 prop, honestly the boat scares me. lol I don't need a 100 mph boat. I am more concerned about blowing fuel out the exhaust. I figure I will be running around 6-6.5 lbs boost. If you guy's can give me your thoughts it would be most appreciated. Thanks
Last edited by powermizer; 12-20-2016 at 08:51 PM.
#2
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One more question. If I run a 30 Bravo one do yo think it will need more rpm to stay on plane. I never had a boat that would stay on plane comfortably below 2800 rpm, but they had larger props. I never had a reason to go smaller.
#4
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I was looking at the 771 and thought it may have a little more overlap than I would want being this boat can have such a low cruising rpm. I do agree with you that the 651 would be awesome for power. Maybe I am thinking to small. I don't know what to think anymore, my mind is jumbled.
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#9
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From: yorkville,il
the crane 651 is what i would[and did ] use for a blown 540.it is a proven cam that works and is not a valve train killer.end of discussion!
i had a twin engine american offshore cat with xr drives with 1.35 gear ratio and bravo 4 blades 34 pitch,could spin them to 6300 rpm.will make power well above 5500 rpm
i had a twin engine american offshore cat with xr drives with 1.35 gear ratio and bravo 4 blades 34 pitch,could spin them to 6300 rpm.will make power well above 5500 rpm
#10
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From: Cape coral, FL



