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-   -   what rpms should i run??? 540ci NA..... (https://www.offshoreonly.com/forums/general-q/243781-what-rpms-should-i-run-540ci-na.html)

baja27 12-09-2010 10:37 AM

302 sport , what you can do is get the heads milled down to increase the comp, you can flat mill them down to 113cc chamber, this will a lot with power and efficiency.

302Sport 12-09-2010 10:46 AM

Was actually just checking that out Haha.....looks like .040 will give me a half point

Rookie 12-09-2010 11:04 AM


Originally Posted by 302Sport (Post 3270453)
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.

302Sport 12-09-2010 11:13 AM

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....

baja27 12-09-2010 11:25 AM

DART intake are the best

302Sport 12-09-2010 11:30 AM

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

Rookie 12-09-2010 12:04 PM


Originally Posted by 302Sport (Post 3270574)
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.

kreed 12-09-2010 12:08 PM


Originally Posted by 302Sport (Post 3270574)
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.

Griff 12-09-2010 12:09 PM

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.

302Sport 12-09-2010 12:32 PM


Originally Posted by Griff (Post 3270609)
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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