Cheapish stroker build

thanks jimbo, I completely understand too. I see the light flywheel comes only with 29 degrees timing and would need off set keyways. I do like the fact you can adjust your timing with the other flywheel and tighten down on a steel hub and for my application I don't think either it will make or break a difference in power. what will hopefully make a big difference is stroking it and what factory head is the best with mod's done to it. for my class I do have to use a factory head with no external welding to it or to the block. that would be a big red flag and would be bumped up with the big block mod class where anything go's.
 
Had a stroker...wish I never got rid of it....was FUN!! had a big valve WF head, Alky Tilly 348, and a 3HP small billet flywheel...quick revving rubber burning FUN!!
 
http://www.fastermotors.net/BIGVALVEHEADS.HTML
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when you install that type of head on something with a big bore (model 15 block for example) do you need to fill in the channel along the intake valve side of the head and out to the push rod area with welder and then go back mill the head straight. giving you more head gasket sealing surface to work with. also when you installed larger valves could you safely port the heads enough to flow good with the larger valves without welding more material on the outside of the head. for example around the intake runner,outside around the bowl area's
fwheady.jpg
 
I either use a mod 15 head since it doesn't have that channel in it or i use a billet head.
Event if you weld the oil passage on an Animal or WF head the large bore of the mod 15 gets pretty close to the push rod chamber.
Another alternative is to weld a 1" deck extension to the top of the block.
This is an old picture. The ones i currently have in stock have smaller holes for the push rods so you have more support for a big bore head gasket in that area.
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with running the stroker crank are you limited to what size piston to run before you get into a balance problem. for example: anybody played around with different brands pistons and sizes to see where your limitations are before you need to rebalance the crankshaft weight.
thanks for any input.
 
delray said:
with running the stroker crank are you limited to what size piston to run before you get into a balance problem. for example: anybody played around with different brands pistons and sizes to see where your limitations are before you need to rebalance the crankshaft weight.
thanks for any input.
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Balance on a four stroke is only effective foe small rpm range. What range are you tuning for?
Does this match cam, pipe, intake length?
 
95 shaw said:
Balance on a four stroke is only effective foe small rpm range. What range are you tuning for?
Does this match cam, pipe, intake length?
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so what your saying the size of the piston(doesn't matter how big)only affects a small part of the balance in these small block animals. I guess I never really heard balance a engine to a certain rpm? I would think if a crank,rod and piston is balance correctly it would be good throughout the full rpm's for: example from idle-8000
 
delray said:
so what your saying the size of the piston(doesn't matter how big)only affects a small part of the balance in these small block animals. I guess I never really heard balance a engine to a certain rpm? I would think if a crank,rod and piston is balance correctly it would be good throughout the full rpm's for: example from idle-8000
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Try this.

https://www.brainkart.com/article/Balancing-of-Single-Cylinder-Engine_6254/
A percentage of overbalance can overcome these factors in a short rpm range to help power production. Builders who have done their research guard the info as it fits their build scheme.

It's not like balancing a tire.
 
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Balancing a single cylinder engine is not difficult, but it is limited. It's also not extremely effective (at producing power or reducing wear.)
With a heavy rotating assembly, you can use a counterbalance shaft, but all of the stock applications that I am aware of are designed for low rpm (3600-ish.)
I regularly pull the counterbalance shaft out of our big Hondas, etc. The balance can be moved up or down in rpm to get the vibration to a range that the engine will not spend much time in. That's kind of the goal anyway. Internally balancing the crank is the easiest way to do this with heavy metal (adding more weight, not so much taking it away.)
Also, when doing your balance, consider your clutch weight (and balance.) Not only the rotating assembly, but the flywheel & clutch will need to be balanced with it.
 
thanks guys for info you have gave me. I guess what my concern was based only on the ARC stroker crank for a small block clone. they specify only to use that crank with a 2.680 up to a 2.756 bore anything larger the crank will need rebalancing,but nothing on the animal stroker crank and for me being new to stroker stuff I had some concerns what problems I could encounter with stroker animal with a larger piston. like Carlson had mentioned earlier about type of clutch's flywheels...etc that too can affect the balance. that I have experience before when running a cheap stamp out steel clutch and then going to a machine billet unit. day and night difference.
thanks inputs.
 
One Fast Kat said:
What is the highest you would turn a stock animal PVL flywheel?????
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They'll safely turn into the upper 8's. 8800 all day long with no failures that I am aware of.
BUT, How a flywheel is treated is as much important as how it is made. Prying, beating, impacting, etc are all hard on flywheels. I suspect that they are rated for 10,000+, but in racing there are never any guarantees and one should always take precautions on the side of safety.
 
delray said:
thanks guys for info you have gave me. I guess what my concern was based only on the ARC stroker crank for a small block clone. they specify only to use that crank with a 2.680 up to a 2.756 bore anything larger the crank will need rebalancing,but nothing on the animal stroker crank and for me being new to stroker stuff I had some concerns what problems I could encounter with stroker animal with a larger piston. like Carlson had mentioned earlier about type of clutch's flywheels...etc that too can affect the balance. that I have experience before when running a cheap stamp out steel clutch and then going to a machine billet unit. day and night difference.
thanks inputs.
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The Flathead cranks will need re-balancing when used in most any OHV application. We don't list specific piston sizes on the cranks used in OHV builds because they are all mostly bigger than what the crank was initially balanced to.

***Billet Crankshaft 2.437 Stroke with a .9985 Journal.
This alloy crank features a true 1/8" journal radius for added strength and durability. Crank is balanced to be used as a stock replacement crank for the 5 HP Flathead modified. This crank can also be used as a +.237" stroker crank for the Briggs Animal, World formula and 206 Intek. When used as an OHV stroker crank the Animal stroker timing gear #6534, Raptor style PTO bearing and seal must be used. OHV re-balancing is required

*** Outer 3rd / 4th bearing supports highly recommended ***
 
Static balanced ? The balance factor would be important .
In order too maintain the same balance weight would need to be added or piston lightened .
 
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I'm not saying that balancing the engine doesn't have benefits but unlike the crank, rod, piston, and flywheel that are always locked in the same relative position, how do you successfully balance a kart clutch with multiple discs, floaters and a drum that never lock up or align them selves in the same place each time the clutch hooks up. These same discs etc always have radial play in them so they don't rotate in a true circle. With the clutch off the engine rotate the clutch slowly in your had and watch how elliptically the discs move. The clutch drum also never locks in the same position or relation ship with the crank either.
 
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