port and polish

[totegote530rider]

hey guys im new here.but have questions how hard is it to port and polish i have a brigss and stratton 5 horse if any one has pics or could explain it that ewould be great thats

 

[Jblankster]

it can be hard and not hard, depends wat you want to port and polish. you can allways have a shop do it for you that works on any other kind of engines (like car engines n ****)

 

[jr dragster T]

i wouldn't recomend it if your a begineer but if its a old engine you could always buy the apropriate tools and give it a shot.

 

[2or3wheels]

Ive never done it and dont know what you need to do that.

 

[Russ2251]

Produces little bang for the buck. Polishing can actually work against you. Look at increasing compression ratio first. Much easier and cheaper (assuming it is an L head).

 

[totegote530rider]

well i no how to do it and its not like i dont no what the hell im doing i have done it on cars just not a briggsand stratton if anyone could help that b great

 

[crazycart]

If its the older style flathead its very easy,just take off the head and take out the valves,get a dremel tool and grind off the casting crap in the intake & exhaust port,then polish the intake port smooth.

 

[totegote530rider]

yeah itsoff a1969 tote gote lol but i will try that thanks

 

[2or3wheels]

well maybe try and rebuild (rings maybe pistion) i have a rebuiuld 5 horse and it easily runs away from any other ive ever used. but that was bored 1 over and has new pistion and rings.

 

[totegote530rider]

yeah its already been done its bored out to almost a 8 horse i think

 

[2or3wheels]

wow u still need more? id sugest if your that hungary go with a torque converter if possile.

 

[hickskateboarder]

how much u guys normally mill your heads?

 

[Jerryburger]

I REALLY WISH I could find the article a go-kart racing team published online about their experiments with a stock B/S 5hp engine. What they did was a step-by-step progression of hop-up mods to the motor, after each step, testing it on a dyno. The biggest increase in HP was putting a 14" header/exhaust pipe on it. I believe the other was converting it to alcohol operation. One odf the cool points they brought up was that within the engines working rpm operating range, the only necessary mod was to replace the rod/slinger with a better arrangement. (The stock slinger was prone to snapping as it struck the oil at high rpm.) What I gathered from the article was that they were pulling almost 7hp at 4400 rpm with just improvements to the exhaust breathing. It was even a bit stronger at 3600 rpm. If I can find this article again, I'll post it or a link to it.
After reading it, I tried running with a 14" pipe, expanding to a 1" pipe fitting at the end, and then screwing on a a large (B/S 8hp low-restriction muffler) onto the end. It was still fairly quiet, and it woke the engine up on the upper rpm range. (This is the grey sickly oil-burner you see in some of pix of the low-rider). I still have the motor, but the HF 6.5 was too tempting to pass up,- the old motor is REALLY tired, mechanically.
Hope this helped.

 

[Jerryburger]

Okay- with much humility and egg on my face, I MUST apologize for brain-memory cells that must've been failing me. I DID find the article I was referring to about the B/S build-up, and although there was a "7" in the HP figure, it was "5.79 hp" when measured with the modification. So that all who wants to can read and digest the information, I'm going to post it under a new thread, "5hp FlatHead B/S Build-up" in the "Engines & Clutches" section. Please keep in mind that this is just a reprint of someone else's hard work; and FULL CREDIT goes to the original author.
...again, sorry about my occasional (?) brain farts.