turntable leads HO scale

Okay for you guys out there with large locos such as challengers and bigboys
what are your typical roundhouse lead track lengths.

I would think the length would be just longer than the longest engine,this would work for me[:)][:)][:D]
JIM

Lead tracks on mine are 24" and 36" Inbound, outbound. Running, big boy, cab forward and Y6b. Need a 130ft turn table to turn them and about 32" min radius on the Big Boy (tender is the problem and looks.)
hope this helps
George P.