Flathead cam help

Mrgofast said:
It is a cheromed piston, that was one of my first challenges. Ive built a couple flatheads and messed around with them but more clome stuff to be honest, im familiar with having to clearance cranks and cams. I figured the cam would be on the small side, i just wondered why they would make such a small grind on am adjustable billet core. The engine rule is 213cc maximum 4 stroke only, no gearboxes. Theres not much for competition in the open class at the moment, as hardly anyone has a true "open" kart ready. The class has been filled with predator motors with basic upgrades running on turf tires so i figured a well-built flathead in limited or super stock trim would outrun a "stage 1" predator no sweat. Brian is your price to sleeve a block $150? I remember reading that somewhere on here.
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As far as I know -- it's been that price for 20 years or more. Now, I do know the cost of the sleeves went up, so contact Sarah in the office for a definite/current price.

The cam may have been originally used in a "cheater" stock engine or even in a class where .233" lift was the only tech on cam and valve lift.

The exhaust reducer can help, sure.

Installing big valves, seats, and guides is not a DIY job. These need to be machined concentric. Any misalignment at all and it's junk.
 
Just for kicks, I built a Stroked flathead.
126 cam , .150 Lunati stroked crank, Tillotson I think a 348 And it will haul the mail. Only raced it once in open and got handed my ssa by a stroked animal. So I built a stoker animal 110 cam tillotson 30 overbore, Arc rod, wiseco, Big valves ported. And it will definitely get the job done. More hp than I can drive .
 
At this point its just for the fun and cool factor, and unless you have deep pockets i doubt most peoples goal on a flatty is to make the maximum power possible. At this point just want to have a durable little bullet that i can upgrade down the road, but not be a roadblock to the ohv guys as i sit now. The rule packet hasnt changed in years but guys used to build crazier engines for the class but either got into stock cars or got injured and quit lol. Since they left the open class has just been filled in by people running the predator class just to get some extra laps each night. You can physially hear that theyre only turning 5000 ish rpm, their engines arent that hot as they sit. Things are a lot different in south texas, anything thats not an open kart has to run any turf tires, and any engine with a cam or flywheel other than stock is considered open.
 

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Chipg56 said:
I can see building an open flatty for fun but it will put you at a disadvantage against practically any OHV engine. All those that are running what seem to be pretty stock China motors can react quickly and cheaply when you start blowing them away.
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6.5hp @ 3600 RPMs for OHV engine.
5 hp @ 3600 from abt same cc Briggs flathead. Even Briggs 20hp V twin 656cc is more powerful than 16hp 656cc opposed, both at 3600. Better flow thru OHV. Just a casual observation from the 2 briggs 656cc engines, V n Oppy, i rebuilt
 
No problem. Have grinder... Can grind. I like to smooth crankshaft rough cast anyway. Less windage in oil m8st... N its a passstime
 
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