Well, I've no experience with pullstarts tbh, it was the very first thing to 'go' on my Hyper 7, way back when...however, I would suggest that the fact that most good engines are rear exhaust, means that there is space behind the engine meant for the manifold/header, meaning that there is also enough room for a pullstart. Further thinking that you can fit ANY big block engine into most buggies, I would say that you shouldn't have a problem to put as big an engine as you want, with or without pullstart. Like I say, the header will take up space back there anyway...why? What specifically are you thinking?