My 15-1 572 uses a stock starter. Header tube nearly touches at the front of the starter. I run 2 batteries and they need a decent charge in them. It starts with 32 degrees, ignition on. It cranks way easier with the ignition off but with the track record of the 440-25 intake exploding thats a no no. I've found the batteries to be more of an issue than the starter itself. Just disassembled the starter for a look see after over 400 passes. Except for some arcing on the solenoid washer and contacts it looked like new.
Doug