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Old 12-24-2006, 11:00 AM
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Default Re: Cam choice help

Ahh something else to look for. Thanks Donzi502
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Old 12-24-2006, 12:37 PM
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Default Re: Cam choice help

I am talking lobe seperation angle. Not install centerline. That will be 109-111 or maybe 112 in a boat engine. Jas
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Old 12-24-2006, 02:06 PM
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Default Re: Cam choice help

Just found the original spec's for the cam that was in the motor.
Duration @.050; Intake .234* /Exhaust .238*
Lift;Intake .271 / Exhaust .282
With 1.7 rockers isnt that (?) Lift; Intake .461 / Exhaust .479

Last edited by f_inscreenname; 12-24-2006 at 03:44 PM.
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Old 12-24-2006, 05:27 PM
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Default Re: Cam choice help

For nat. asp motor, a 110 LSA is ok in the 218 range. When you get in the 220's a 112, 230's and higher you need a 114.

Now, that statement is very general. The biggest thing to worry about is valve overlap vs water in the exhaust, because LSA and duration directly affect overlap. If water in the exhaust is not an issue, then you run a cam that gives peak performance and that will let you idle at the dock.
So just because you have wet pipes doesnt mean you must have a 114 LSA. Just to give some ridiculous examples; Crane cams 964021 has a 110.5 LSA but both the intake and exhaust valves are closed for 23.5 degrees of crank rotation. How? Duration is only a 192/203.
On the other hand I run a Lunati cam thats a 252/263 114 the valves are open for 29.5 degrees of crank rotation. I wouldn't dare put that in anything but "dry" pipes.

Oh, and just for the record, a 109 intake centerline is very popular. Usually is a good all around install.

DAVE
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Old 12-24-2006, 06:10 PM
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Default Re: Cam choice help

I will have to read this one a few time to understand but I think I get it.
Thanks again
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Old 12-25-2006, 02:07 PM
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Default Re: Cam choice help

I used the 230/544/109(lunati#LUN-00024LK from summit racing $136.88 with lifters) cam in a 454 oval port open chamber flat top cast pistons motor that came from a 1974 car.Very low compression motor,maybe 8.0 to 1.With it I used a weiand single plane xcelerator intake,750 vacume out of the box holly, basset wet headers and new rings and bearings.It pushed a 23 daytona v-drive to exactly 80(75 with old glenwood logs) with 15 pitch prop and 1.14 gears turning 5200 rpm.Don't know if it made any power after 5200 but it did pull nice from idle on up.If it was getting water in the motor I never new it.I have no idea how much power this low performance/low $ set up made(350-400?).It was easy to drive and idled nice and strong with only a mild lope at 600.I,m not a motor man but this cam worked GREAT for me.Of course every boat and motor is different.I think this cam is a good candidate.Hope this helps
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