Cam and valvetrain longevity....??? low duration high lift...
09-24-2016, 08:31 AM
#501
Platinum Member
Platinum Member
003 in the hole , .039- .041
0 head gaskets with .0065 wall and they touched hot enough to knock the ring seal out of the tightest one's but not physically damaged the piston but gimmefuel ran .027 head gaskets with a motor close to zero and it beat the Pistons right out of it, this isnt nascar, if they dont hit hot at first they will when they get some carbon, fwiw, Smitty
09-24-2016, 09:48 AM
#502
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I am a few weeks away from my 540's being finished. similar to Tim, Bob M. spec the cams and heads. afr 325 114 cc the cams are 242.2 664 on intake 247.1 656 on exhaust flat top JE pistons, merlin 3 blocks zero deck and the head gasket he set me up with from cometic is .027. I am running Nickerson 4150 on merlin single plane intakes. carbs flow 994 CFM. as soon as the engines are complete they are going to Nickerson for dyno and tune. I will be happy to provide the results here. I can find out from my builder what the final comp. ended up, our target was 9.8 :1. will post more info as I get it.
09-24-2016, 02:09 PM
#503
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Tom,
The compression ratio will increase from 8.52 to 8.69 with the move to a .027” gasket from a .039”. That is an increase of .17 of a point and while that may seem insignificant, any increase is worthwhile at that low of a ratio. A .035” piston to head clearance is ideal in a sub 6000 RPM engine with a steel connecting rod. I would advise you to check the RA of both deck surfaces to verify the finish is compatible with a MLS gasket.
Bob
The compression ratio will increase from 8.52 to 8.69 with the move to a .027” gasket from a .039”. That is an increase of .17 of a point and while that may seem insignificant, any increase is worthwhile at that low of a ratio. A .035” piston to head clearance is ideal in a sub 6000 RPM engine with a steel connecting rod. I would advise you to check the RA of both deck surfaces to verify the finish is compatible with a MLS gasket.
Bob
As stated, this isnt nascar.
Gold Member
09-24-2016, 04:50 PM
#506
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Lets not get off topic just yet. We havent hit 50 pages yet. 
I wonder what the science is, behind the fact, Timmys 540ci engines, with AFR 325 heads, got a 241/246 cam, and the tight quench guy, gets a 242/247 cam, with a little less lift? Both have flat top pistons, 4150 carbs, both heads milled to 114cc... Why the change?
I wonder what the science is, behind the fact, Timmys 540ci engines, with AFR 325 heads, got a 241/246 cam, and the tight quench guy, gets a 242/247 cam, with a little less lift? Both have flat top pistons, 4150 carbs, both heads milled to 114cc... Why the change?
Last edited by getrdunn; 09-24-2016 at 04:52 PM.
09-24-2016, 09:03 PM
#508
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09-24-2016, 09:10 PM
#509
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what kind of power did you make with the dominator? what intake did you use? was intake matched to heads?
