Valve Adjustment Question

GearHead36

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LOL
How many more hp do you get?
I used to build 5hp B&S engines for WKA stock, stock appearing and outlaw classes. I have degreed and plotted many stock and aftermarket cams and put engines on a dyno. If you can tell a power differece of a couple thousands lash on a fairly low compression 3600 RPM governed engine I'd like to see that on a dyno. The old flat head briggs with the "easy spin" bump on the cam it did make a difference. Opening up the lash to defeat the compression release bump would give more low end torque and minimum lash gave more lift and duration and higher hp. All this at the 4000 to 6500 RPM powerband measured on a dyno and the difference is still small.
Where did you race? My dad and I built and raced WKA stock & modified using Briggs 5HP flathead engines. We raced in upstate SC and western NC. I re-set the lash on the modified engine after every race, and we raced weekly. I can tear down a horizontal shaft Briggs flathead in my sleep. I'm sure you can too.
 

Hammermechanicman

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My butt was too fat for me to race LOL. I just built engines for folks in southwest ohio. There was a local guy that quit building 5hp briggs to concentrate on 2 strokes as that was where the money was. I picked up a lot of his 5hp briggs business and i had access to his dyno and engine building books.
You must have been running one of those super fast ramp speed Dyno Cams that beats the hell out of the valves and tappets
 

GearHead36

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My butt was too fat for me to race LOL. I just built engines for folks in southwest ohio. There was a local guy that quit building 5hp briggs to concentrate on 2 strokes as that was where the money was. I picked up a lot of his 5hp briggs business and i had access to his dyno and engine building books.
You must have been running one of those super fast ramp speed Dyno Cams that beats the hell out of the valves and tappets
I was a skinny teenager at the time. "super fast ramp speed Dyno Cams"... Nope. I think my "career" was before those. Late 70's. Most of the aftermarket engine parts were Horstman.
 
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