You didn't ask that. You asked if you COULD BUILD A BUGGY FOR 5K. And the general answer is no.
Now if you asked COULD I BUILD A BUGGY FOR 5K ADDITIONAL, I HAVE X, Y, Z.... thats a different question.
Now you also needed/wanted to ask IF YOU WERE GOING TO TRY TO BUILD A BUGGY FOR, SAY 5K, AND YOU HAD THE MAJOR COMPONENTS (egine, tranny, axles), WHAT WOULD YOU DO.
Ask the right questions, get the right answers. Beat around the bush, then get all bent out of shape.
Also, while I agree that the engine, tranny and axles are a big portion, I don't think that for a full, from scratch tube buggy, they are even 1/2 the final cost. Unless you got lots of scrap laying around and like making all your brackets and such (which its just so easy and more cost effective to buy now).
Poop Pipe links, tractor heims, simple (home made) brackets, 1/4-elliptical spring packs, decent cage made at home, scab in a firewall (to get brakes, petals, steering wheel etc), sure, you could probably do it. To bring the sexy and not make it look like a back-yard scabbed together rig. Either a lot of time to make everything super nice, or more $$ for better raw components.
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