4 HP head 1 tab???reliefs cutthe combustion chamber on the one ARC is considerably smaller. I always liked that one. I have one of the higher compression small chamber Briggs head
There's no doubt that a billet head can transfer more heat from the combustion chamber. I'm guessing that would mean you could run it leaner, with a colder plug and higher CHT readings.
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I'm going to guess that it does add value. How much? That depends, I suppose, on how good a set up man you are. If you know how to tune to take advantage of the head, I can imagine some gains. I'm thinking, if you just bolted it on and don't change your tuning procedure, the gains could be minimal. There's no doubt that a billet head can transfer more heat from the combustion chamber. I'm guessing that would mean you could run it leaner, with a colder plug and higher CHT readings. Not that the CHT tells you much, I prefer the EGT, but whatever.
One thing, it costs money to go faster, but, as the gains become smaller and smaller, the price goes higher and higher for each increment of gain.
UOTE="Lkerley, post: 803128, member: 22706"]
Is there any benefits on a s/a motor adding a Finned billet head or is benefit not worth the price ...stock valves,.060 over,stock lift Dyno cam.if so what cc.
Assuming a perfect casting.Maybe to elaborate just a touch on Al's statement
Two of the most common alloys (A356 for castings, and 6061 for billet) have absolutely identical specific heat capacity, though thermal conductivity is a couple percent better in 6061.
Point being: when it comes to thermal conductivity and capacity, simply saying "billet is better than cast" is not necessarily true -- it depends on a number of other factors like alloy, mass and design/shape.
PM
Actually, in a low compression engine, a low octane fuel will actually produce better horsepower. Octane is only a measure of a fuel's ability to resist detonation. High compression engines produce more horsepower, but they need higher octane fuel to do it.limited on timing.and overall HP with 87
That's what I was thinking it's 1 cylinder not 8The problem is that the CCs of the combustion chamber don't change. You can increase cubic inches, you can increase rod length, piston speed, etc, but you can't decrease the size of the combustion chamber much more without killing all of the airflow. That's a limitation of the flathead design.