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Repower 3112v

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I'm going to be blowing snow this year and want all the power I can get. We average about 120" a winter, and will be coming off a truck with a plow. I know it will be a huge step down but I'm tired of fixing the lawn every spring.


I have a functional 300000 Briggs but will need a starter/generator.

Option two. bore the cyl and rebuild it to a 320000. Is the crank and all other dimensions the same so that seals and such are interchangeable?

Option three. Plant an 18hp Vanguard on the end of the driveshaft. Has anybody done this? I'm sure the muffler will be a problem to deal with.




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There is no doubt that throwing snow requires the most hp out of these garden tractors, more than any other attachment.  The more the better, that being said, you have a variable so you should not have any problems with managing the forward motion (stuffing the thrower)  to the capabilities of the engine.  I had an engine that was bored from a 30ci Briggs (old style external balancing gears like you probably have in your 3112) to the dia needed for a 16hp (32ci) piston.  That was all it needed, was bore it, new piston, rings  and rod.  Nothing else was changed and it ran great!

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the 12hp 30cid was governed at 3400rpm i have no idea what briggs was thinking since cranking it to to 3600rpm will tweek it to 13 - 15hp and advancing the timing a tad bit replacing the points with a nova 2 ignition module will help also.


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Same valves. Same crank. Same head.


I have the original literature that came with it. There is a 6 page insert for the Briggs engine that looks like it was printed by Briggs & Stratton. 300410 to 300424.  Max torque 21.2 @ 2600 rpm. Horsepower is as follows. 6.68@1800rpm 9.65@2400 11.63@3000  12@3300  11.80@3600.


I did some porting of the intake on the last one I built (320000). Maybe it helps the high rpm operation. I just know it's plenty strong. If I make this in to a 320000, I'll have a look @ the flow around the valves. Perhaps massage the head too, then have it milled to make up for any material removed. It kind of looks like I'm going to be diving into this engine. 


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