At one point i thought about doing this in a SC8. But found out real fast its allot of work with just one truck. Post some video when its done, sounds like a fun project.

Only reason I'm using this instead of one of my Jammin X1's is this one already had body mounts for some cheesy ford truck that didn't cover the tires. Plus, it's just a little narrower than a jammin and a Slash body fits almost perfectly.

I'm debating on putting the slash/SC bumpers on it yet. Probably do a rear for looks, but not the front.

The buggy is an OFNA clone and all old ofna parts fit...Saves me from ordering from Singapore.

I'm figuring a final gear ratio of ~ 2.5-1 should allow me to get the speed I'm looking for and still use the torque of the 4stroke to pull me out of the hole. I'm not going to be racing this at all, just something to wow my friends with LOL.

I WILL say, using the OS .40 made for a car was much easier than having to modify an engine to work. Flywheel and crank all accept standard 1/8 parts...and flywheel is HEAVY.

Storydude1 - if You are making a 4 stroke, You have got to post a video on Youtube.. Needs to be on a track..

Oh, I will

Not a formal track, just my backyard 100X80 track the real track is an hour drive from here.

Hey, did you get the $$$ for that starterbox yet?

Cool. I see you have some room then..

Nice. Want to see torque in action..

IT LIVES!

Had to reset cam timing, a few adjustments and its a runner. Had to shim the hell outta the clutchbell(built for a 2speed pinion) bend the crap out of the clutch springs to make them light enough and lean the crap outta it.

It fires right up, no exhaust pressure needed for fuel draw, revs to what sounds like mid 20K's and blows up tires right off idle

Tomorrow evening gets it it's first taste of dirt.

if it only revs to 20k do you have it geared higher? Like 25 tooth CB??

I made it all the way to 22t bell, but the clutch shoes start wearing very fast at this point. And it puts a hugh load on the engine, temps then rise very fast.

Ok, you got to get some video also.. I really want to see this run.

I have to see this!..

22T bell, 46tooth spur. IIRC, it's a 2.3:1 ratio...A little high, but I can work down. optimum should be ~2.0:1 or slightly less.

I'm using some hard shoes with added weight and .9 clutchsprings bent to be really light.. No wear as of yet, but I haven't had it on the dirt yet...I can see wear being an issue though....
soon. Very soon

Ok, tests a few min ago proved I do not need a fuel pressure line. So, without needing a line, I can eliminate the pipe. Vertical stack out of the SC truck bed, or route to side and exit low in front of rear wheel? I know routing to in front of rear wheel will look more realistic, but a big honking stack out of the bed has it's merits

A pipe isn;t needed to make power and actually I think it's hurting performance...Seems to get dead spots in the throttle curve. I'm assuming from a 2 stroke pipe's tuning screwing with the 4 stroke exhaust pulses.

On a side note, anyone have a beater SC body laying around? I'm painting a nice one for show, but to test I want nothing even near nice...just solid. Also, I'm thinking a fan of some type might be in order. Temps are 325-335 on the bench, with little load. It's not smoking or smelling burnt, but again, no load.

From experience, No fuel pump or pressure line will cause lean conditions while running. I think thats why your getting the dead spots while driving. Though i dont know your carb, fuel tank position. So if your fuel feed is higher than the carb you should be ok. As for the temps at idle, they are very high. Had the same issue until i added the fuel pump. They then would be around 200-220 idling, and go up to 350 while racing. And thats with a fan setup running off of flywheel, so fan is slower at idle-faster while on the gas. I also tried an electric fan setup, no go, not enough air flow.

And i tried using crankcase pressure to fuel tank. That works but varies with speed of engine. So you get inconsistent performance. Now if you could fit a pressure regulator in there it may work, have not gotten that far yet. And if anyone could recommend one ill give it a try.
As i think the regulator setup would work awesome. The fuel pump is still kinda iffy when it gets dirty.

DPbuggyboy, who I bought my OS 4-stroke from, recommended the Perry VP30 pump:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXDG59

It should be a little fragile though, so it is important that it is mounted in a way so it doesn't take to many bumps. And the closer to the carb it is placed, the better.

There's also RCV:
http://www.rcvengines.com/rcv58cd.htm