Exhaust Port Question

[STreetKArt]

is it fine that i bored out the exhaust port threads on my 5hp or is that going to make it loose power

 

[modelengineer]

It will be fine. It looks like you have a flange mount for the exhaust anyway, so you don't need the threads.

 

[newrider3]

You don't want to make the ports any larger when you're porting a small engine. The stock Briggs threaded exhaust was too big stock to begin with, so yes, you probably dropped a small amount of power.

 

[Kenny_McCormic]

Shave the eyebrows off if you want more power. All the hidden power in a flathead is in the head/deck.

 

[oscaryu1]

WAY too big. Overport IMO.

 

[jr dragster T]

Take some measurement's of your port and let me know. Realy the thread's arent too deep so he didnt remove any more than probably 1/16".

 

[oscaryu1]

Yeah but still, this is just a mildly modified 5HP. He ain't running a stroker crank, or a 4.5" rod and Wiseco piston... it's overkill for a 5HP.