QJ8F- We've been asking for some pics to help you determine if you're into a feasible project, or a total rolling crematorium. You keep telling is that it's strong, heavy, or "nearly solid steel".Don't take offence, you're new at this- so, you're probably the last person that can make a determination as to the feasibilty of this project. We're not trying to pee out your campfire, it's just that death sucks. While that may sound funny, I assure you that it isn't.
The structural integrity of the frame is indeed important. Not just the material thickness, but the diameter, the design, the geometry, the welds- he//, even the type of steel used. And that's just the frame! Now, you have to consider-
Hardware- Crappy ungraded hardware store stuff? Or worse, Chinese hardware?Do you really want a critical fastener failing at 60 (or more) MPH with all that weight and inertia behind you?
Brakes- I can't believe I still have to explain this to people. Your vehicle MUST be able to stop at least as well as it can go. If not, you're dead. Simple. Kart like that? Settle for nothing less than 4-wheel hydraulic discs. And not cheapo pitbike crap either. Your life depends on it.
Steering- Not just "does it turn when I turn the wheel?". Steering is a system, not just some components. It is geometry, hardware, and components. Again, no room for compromise here. Either it's engineered properly, or tell Darwin I said "Hello".
Bearings- Did anybody think of that? Can you just imagine $2 LOW SPEED bearings at 60MPH? Disintegration, followed by catastrophic face failure.
Control linkages/cables. Key word here- "control".
If I can summarize all of this in a tidy little package for you: Think about what you're doing, and be honest with yourself. Are you competent enough to properly evaluate and tackle this project? Is this chassis REALLY up to snuff? Think about it. These may well not be the words you want to hear, but then again, too bad. I'm not going to encourage you to try out for a Darwin award. Sorry.
So take the fellas' advice here. Either make dang good and sure you've got a legit, quality race chassis and skills, OR toss that engine in a good buggy, OR sell that engine and put something more appropriate in your kart. Just my 45,238,852 cents...