12hp briggs tips and tricks

[strokerwheelhorse56]

im building a 12hp briggs stock prepared for vo tech any pionters would be really heplful. im thinking of putting a 18hp carb on it flywheel key valve springs and retainers, ported the intake a little and an e3 spark plug

[strokerwheelhorse56]

okay I'm going to clear up some myths here feel free to correct me if I'm wrong. if you retard the cam a degree you risk sucking a valve . there aren't any cams that can be swapped from one motor to yours to get more power. if you want a cam I recommend ec or precision cams (they're cheaper) .

for small builds I recommend a flywheel key #3 or #4 ,shave the head or 11hp head e3 spark plug ,air filter , valve springs and keepers from ec. do some port work all an engine is, is an air pump the more in the more out so you want it to flow smoothly. get a cheap dremel from benneys or walmart .after you take out some material you need sand paper from 100 grit up too around 600 after sanding use a good polish.you may want to remove the govenor depending on your class.  did I miss anything?  feel free to add   

[The Tank]

Wish I could be of more help but I'm not a fathead guy (oops I meant flathead) you plan on doing any mods to the engine I'd definitely upgrade to an ARC billet flywheel. As for the porting on an engine, most think bigger is better but you can actually hurt your engines performance. I'd highly recommend letting someone with a flow bench do the work. You are correct about governor, solely depends on the class but remember, governed classes is a completely stock engine class with an air filter and exhaust upgrade. With that being said, you cant modify the engine at all internally. If you do decide to move to an ungoverned class, you have several cam folks out there. Here is a few, Isky cams, Hitchhiker cams, precision cams, or dyno cams. As for other parts EC is a good source. I'm not sure you may can get a custom cam from them as well. You should do a search about the E3 spark plug, I'd stay away from them. Search the E3 spark plug using the search in the upper left side of the screen. You should find that interesting. Not much of a help but told ya what I know.

[Rooster]

Did I miss something here or did he answer his own question?

[strokerwheelhorse56]

yea I pretty much did ,thanks I only knew about precision cams and ec I'll check them out. there is a machine shop down the road called f@h gonna give them a call tm. any idea of how much I can shave off my head? I'm thinking.040 sounds good I have the machine to do it myself in vo tech. thanks for the help

[Rooster]

If you put any kind of cam in that you do not want to shave the head.

[strokerwheelhorse56]

okay thanks, I have a 18hp carb from a opposed twin. would this be too much fuel for it I'm thinking it would make it run like an ape woth a cam

[cycloneracer]

I doubt it.

[strokerwheelhorse56]

oh okay so id be better off getting a carb from ec?

[royalblu68f100]

Yes.

[strokerwheelhorse56]

alright I'll have to do that when I've got some coin in hand,but for now would it do me any good to put it on? I made an intake manifold already just never tried it out.

[racer17j]

okay thanks, I have a 18hp carb from a opposed twin. would this be too much fuel for it I'm thinking it would make it run like an ape woth a cam

the amount of fuel a motor gets is determined by the jet size the amount of air you can mix with it is where the carb bore size matters. you can adjust any carb to deliver to much fuel by throw'n a huge jet in it . you could also try a autolite 1039x plug it's a racing plug with a long reach and no gap.we run them in our kart motors and they help because they are hotter spark and the take up more room in the chamber so it boosts your compression a bit.i tried on on my cutter jusyt put 4 washers on it just because i didn't have another plug in my box so never messred just how deep you could go with it

[BIG AL 202]

Reseach [with the search botton on the left, works better] mods in history, lots of real good advice. G-team has a good beginner dvd for building the 12hp flatty. Before you spend your hard earned money research and get a plan that fits your class rules!

[strokerwheelhorse56]

thanks everyone ive recently bought a rod .im debating who to buy a nasty cam from ec only runs a .410 lift and precision is boasting a .453 I've yet to contact Don . im looking for a ton of ton of low end with great mid to high rpm range.

[Rooster]

Tim Isky - www.smallenginecams.com