What is the rated rpm for the old briggs L head 5hp horizontal motors? I realize there is a racing line of parts and motors but I was wondering if you can run these motors stock any higher rpm and still be safe.

There rated at 3600 rpm's

Yes they are set to run around 3,600 rpm... anything else is asking for it... but I've had them running fine at around 4,000 rpm...

if you want to run more than 4000 RPM what will i need? (i know for sure a milled head... hotter plug, better exhaust, better carburetor.. forged rod, crank, and piston, bore cylcinder and carb... maybe a meth carb, am i missing something?


(i need this info too)

If you were going to spend that much money on a old briggs engine that parts would be hard to get. You should buy one of these new Briggs Racing Engines.

http://www.briggsracing.com/display/router.asp?docid=101243

These engines aren,t cheap, but they are fast. Plus all types of speed parts to make them faster.

No your not missing anything...
But I have.. not saying safely but they have never flown apart... briggs engines at or above 4,000 rpm stock... before I replaced the 12hp engine.... I had that running pretty fast.. I can't tell you how fast exactly as I never checked.... only thing I did to make it do this was tie a string to the governor and hold it all the way back..., so you can guess it did some rpms... but the key was I never held it there for very long... maybe 5 minutes at the most..
Your just asking for anything to happen with a stock engine, making it do over 3,600 rpm... Just telling this to warn you, because there is the possibility of the rod splitting.... blowing through the crankcase essentially creating a fragment grenade..

If you were going to spend that much money on a old briggs engine that parts would be hard to get. You should buy one of these new Briggs Racing Engines.

http://www.briggsracing.com/display/router.asp?docid=101243

These engines aren,t cheap, but they are fast. Plus all types of speed parts to make them faster.
He does make a point... unless you do the work yourself... and the engine was free... parts found cheap, its not really worth making a stock engine do more then what it was made to do..
Usually e bay has parts for these engines cheap.. but they do go fast.

i dont think the raptor 3 is even worth it. its expensive, and expected more HP with it. just get a stock briggs or something , better stuff and that would probably beat the raptor3