[mopar4u]

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.

 

[tommyj3]

There rated at 3600 rpm's

 

[bugman]

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...

 

[oscaryu1]

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)

 

[tommyj3]

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.

 

[bugman]

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..

 

[bugman]

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.

 

[oscaryu1]

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