5HP Briggs Intek on Meth.

[Ray J Neal]

I purchased a stock 5hp briggs i/c intek ohv for my boy-- we are going to build him a kart. Funny to come here and ask these questions as I am a Master Toyota technician.
Hes ordered the 92ss cam, comp springs w/ retainers, arc billet con rod, ebay race head, and a little header pipe. I have made up my mind it absolutely must run on methanol.
I'd imagine the butterfly style carb will not work due to the rubber within the unit.
HERE IS MY QUESTION:
To run meth I need to get a slide carb. Is there any meth carbs available (link please).
Do I need to replace the Main, pilot jets, jet nozzle and nozzle diameter? Can I get a ready-to-fly alky carb?
I imagine I will need a fuel pump to deliver double the flow/minute of said fuel?

Bottom line here is, based on what he is ordering, and what I have asked, will this cover it for the alky setup? Fill me in with your guys knowledge/experiences.


Ray

 

[Kaptain Krunch]

Normally im not the one to suggest a billet flywheel, but if your doing that much, its really a must.

As for running meth, i have no clue.

 

[frederic]

Straight methonal (and alcohol) requires a 20% jet size increase over what you'd use for gasoline for the same hardware.

You also need to replace all of the fuel line hoses with alcohol-compatible hoses and I believe (but not sure) that a plastic gas tank would dissolve over time, though slowly.

 

[newrider3]

I hate to tell you, but it sounds like you've been ordering parts for a Briggs 13 series Flathead, when you have a newer OHV engine.

 

[Ray J Neal]

OUCH. He's been ordering. I can always resell what we can not use. I guess lets ask this question, starting from square one.
What has more readily available/cheaper parts and more aftermarket support and capable of more power output..the newer OHV or flathead engines? I can get a killer deal from a buddy at the machine shop on a Raptor that someone never picked up, but seems parts are more and more scarce since being discontinued.
Really, which online suppliers stock the most aftermarket support for the 5hp ohv and/or flatheads?

Ray

 

[Rotore]

why not sell and get a 200cc 4stroke and turbo

 

[EagleTalons]

OUCH. He's been ordering. I can always resell what we can not use. I guess lets ask this question, starting from square one.
What has more readily available/cheaper parts and more aftermarket support and capable of more power output..the newer OHV or flathead engines? I can get a killer deal from a buddy at the machine shop on a Raptor that someone never picked up, but seems parts are more and more scarce since being discontinued.
Really, which online suppliers stock the most aftermarket support for the 5hp ohv and/or flatheads?

Ray

The OHV can put out more power and the parts aren't being discontinued. Also Rotore is right. Get some sort of MC or Sled engine if you want some serious power without having to worry about rebuilds.

 

[brendonv]

But rebuilding is fun plus it will teach the young block about mechanics. Sucks ya ordered the wrong parts but u will be able to sell em on ebay for the same price u got em for. U may loose some money on shipping but o well. U wont do that again haha. Sometimes u gotta learn the hard and expensive way. I have done a few times. The flat heads have more aftermarket parts but OHV is more powerful. Hrmm not sure. Well happy modding. XD

 

[anderkart]

To run meth I need to get a slide carb. Is there any meth carbs available (link please).

Tillotson and Walbro have serveral Meth carb models: http://www.eccarburetors.com/ (you can also check out/post at they're carb forum)

You'll also find a wealth of motor/carb info at these forums:
http://karting.4cycle.com/forumdisplay.php?f=1
http://karting.4cycle.com/forumdisplay.php?f=71

 

[Kaptain Krunch]

Get some sort of MC or Sled engine

Now your learning.

 

[slideways]

Not sure why you want to run methanol for a yard kart. Much more maitenance and tuning for not that much more power.

What you are basically building is a Briggs Animal. You are starting with a cheaper motor to begin with in that it probably has an aluminum bore vs a cast iron sleeve. It also has a different head, bushing flywheel vs a roller bearing block, and a different rod and carburetor. What you can do it hit the karting forums and look for stock animal takeoffs from guys upgrading and build from there. Get an ARC flywheel, billet rod, animal head and valvetrain and a Mikuni PZ22 carb (jetted for gas or meth whatever you decide). At that point you almost have a stock animal which produces between 8-10hp. The motors cost about $500-600 new.. so theoretically you can get there for $350 or so.. but you wont have the cast iron sleeve, the upgraded ignition and the DU Bearing in the block..

 

[Kaptain Krunch]

For 350 you could buy a nice sled or bike engine with at least 50hp.

 

[Rotore]

or go to the junk yard and get two big as$ v twins 18hp or so then weld then together to get a v4 or get 6 flat heads and weld them together to get an inline 6. Jk

but a 20hp v-twin and a mc gearbox would work and there you have a learning experience

or save the time and money and get an mc engine like 125 2-stroke or 250 4-stroke

 

[Ray J Neal]

If I found a kart chassis set up for/with a 5hp briggs on it, would the 125cc lifan swap be pretty straight forward? Mounting would not be an issue as far as fabrication.
And I continuously hear claims of ~60mph with modded briggs animals in these little karts. Does that sound about right? After riding my buddies sons (err, yea..more like my buddies) kart which has a raptor modded to hell I can believe that 60 is reasonable. I don't think my boy would need to go any faster (and I could still have a blast!).

 

[brendonv]

Well with a stock briggs 5hp ur lookin at like 30-35mph depending on ur gearing. Thats plenty fast for u and ur kid.

 

[Rotore]

If I found a kart chassis set up for/with a 5hp briggs on it, would the 125cc lifan swap be pretty straight forward? Mounting would not be an issue as far as fabrication.
And I continuously hear claims of ~60mph with modded briggs animals in these little karts. Does that sound about right? After riding my buddies sons (err, yea..more like my buddies) kart which has a raptor modded to hell I can believe that 60 is reasonable. I don't think my boy would need to go any faster (and I could still have a blast!).

is the lifan a 2 stroke or 4 stroke? does it have a gearbox or not?

we need info dude but yes it is a straight forward swap.

 

[Ray J Neal]

Scratch the Lifan.
I finally found somewhere to get a hold of wiseco pistons for the Animal.
Does anyone have experience running the 9.6:1 comp piston on meth? It's odd to not see higher static compression engines. My 68 Camaro with blown BBC is on methanol and comp is 14.1:1.
I imagine a lot of you race and are limited to what the rules allow. However, me and my buddies are just going to play in a parking lot and I want the baddest 5 horse Briggs!
My boys setup will need to follow regulations, however. But this post is about MY desired setup.

Ray

EDIT: I found a kart I want to look at this weekend. It has a stock animal on it. Would it be compatible if I added an aggressive cam, dual springs, the wiseco 9.6:1 piston and jetted the carb for methanol?

 

[jr dragster T]

9.6:1 isnt that high of compression for gas let alone alcohol.

 

[Rotore]

why scratch the lifan?

 

[Ray J Neal]

9.6:1 isnt that high of compression for gas let alone alcohol.

No it is not at all. The blown BBC in my Camaro is on Methanol and static is 14.7:1.

I am picking up a a kart this Saturday. It's a Margay chassis, stock Animal motor, electronics included, 16 gearsets, has a hastman (SP?) clutch, and three sets of slicks for $800.

Now, 9.6:1 with the Wiseco dome is not high at all. Are there shorter pushrods available if I mill the head? Say .030"-.050" machined off. Depending if it is set to zero lash I would need respectively shorted pushrods otherwise amount of material removed, minus lash, would be the length needed. Or would I be able to mill and reuse the stock length pushrods? Seems the geometry of the rocker arm angle would be a bit off.
You must remember I am thinking in terms of 800+ whp blown alcohol not 10+ horse single cyl engines!

EDIT: Obviously no one can tell me exact amount that can be safely removed from the head. Best course would be to install the higher lift cam, torque cyl head with old head gasket, remove valve springs and check piston-to-valve clearance with a dial indicator, subtract thickness of headgasket, allow .030-.040" clearance for rod stretch and then mill the head that much.
Obviously it would be pointless to run alcohol until a higher compression ratio is achieved. What I am asking is the most logical way to achieve it.

Thanks for the help y'all.