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what rpms should i run??? 540ci NA.....

Old 12-09-2010, 10:46 AM
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Was actually just checking that out Haha.....looks like .040 will give me a half point
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Old 12-09-2010, 11:04 AM
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Originally Posted by 302Sport
Heads aren't an option this winter. So I'm stuck with them for now.
IMO I would put the best cam in for now and let the heads and carb be the limiting factor.
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Old 12-09-2010, 11:13 AM
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thats what i was thinking........i was going to go with new intakes this year too. what would my best choice be?? it had victor jr's with 850's and spacers before....
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Old 12-09-2010, 11:25 AM
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DART intake are the best
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Old 12-09-2010, 11:30 AM
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does anybody have any real HP numbers for different intakes?? I heard that all of the single plane 4150's are pretty close out of the box
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Old 12-09-2010, 12:04 PM
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Originally Posted by 302Sport
does anybody have any real HP numbers for different intakes?? I heard that all of the single plane 4150's are pretty close out of the box
Go with the Dart single plane now. JimV (Valako race heads) is working with Dart right now to cast his hand ported cylinder heads. The new casted heads will mirror his hand ported heads, with runner volume, raised intake floors and air flow velocity. This should make it cost effective to have hand ported heads within the price of CNC'd heads. He had the first 7 sets casted about 3 weeks ago. This would be a good combo for you.
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Old 12-09-2010, 12:08 PM
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Originally Posted by 302Sport
does anybody have any real HP numbers for different intakes?? I heard that all of the single plane 4150's are pretty close out of the box
Agreed out the box about the same. If your gonna do any porting then have him port match the intake. Not too expensive, and every little bit helps! If your not dynoing, no way to tell which one works better with your combo. Sometimes, a 1" or a 2" spacer under the carb makes a pretty good difference too. But, your not dynoing so doesnt matter.
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Old 12-09-2010, 12:09 PM
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That cam is pretty mild for a 540. The cam in my 454ci/525SC had about the same lift.
I'd guess that both the cam and carb both start falling off fast around 5300rpms.
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Old 12-09-2010, 12:32 PM
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Originally Posted by Griff
That cam is pretty mild for a 540. The cam in my 454ci/525SC had about the same lift.
I'd guess that both the cam and carb both start falling off fast around 5300rpms.
you think on a 540, about 5300 is max rpm for a 850 holley??
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Old 12-09-2010, 05:24 PM
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The 850 Holley will be adequate for a 540. Mill the choke horn off and radius it if you can similar to the HP Series carb bodies. The used cams listed earlier would be a great choice. I agree most all single plane manifolds are the same at up to 5500 rpm, but use it for better fuel distribution. If your in salt water, get the brass insert version for the water jacket area. I have dynoed 540 N/A engines with single plane manifolds, 4150 series carburetors, and have tried 1/2", 1", and 2" HVH supersucker spacers, they all hurt the torque and power output. At best the spacers did nothing. I feel the plenum volume is already big for 5500 rpm.
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