Actually there was a Corsair variant specifically meant for ground attack
The F4U-6 was re-designated the AU-1. It used a single stage two speed engine of the "C" series and performance at altitude was well below that of some of the older Corsairs.
If it had 115/145 it looks like an exciting ride at low altitude.
According to this:
http://www.alternatewars.com/SAC/AU-1_Corsair_SAC_-_1_June_1953.pdf
the often quoted 238mph is while it was carrying TWO 1000lb bombs, TEN 260(250?)lb bombs and one 150 gal drop tank. It was slightly faster carrying TWO 150 gal drop tanks, ONE 1000lb bomb and SIX 500lb bombs.
A bit late for this poll being built in 1952.