In a corner, front steer tends to go into understeer in bump, while rear steer tends to go into oversteer. So most oem's went to front steer because it tends to be more stable, gives more room for exhaust routing, and allows the engine to set lower in the chassis. With the limited suspension travel and lack of corners (hopefully) while land speed racing, I'd just go with whatever you find. Pinto racks are front steer and they are readily available and relatively inexpensive. Most spindles have Ackerman for front steer. It also gives you more room for collapsible steering column in a body car. my 2cents.