i just picked up a 1999 31sxt and was wondering if someone could tell me the size of the fuel tanks? Also it has B-1,1.36 with XR internals (lwp and no nose cone) would I see any speed increase with imco std lowers? It has stock HP500 efi's.
I was told it runs 93 with 30s and 98 with 32s labbed.

My buddy picked up a ton of mph on his with imco boxes and -2 lowers. Said it was like a new hull

It has boxes... but read that if you add -2 shorties it needs a tunnel tab to get on plane, which it does not have...that's why I was wondering if adding std length Imco's,the nose cone would add a any mph?

Before buying mine in '03, I test drove another (the all yellow on that Ed Champion has for sale with blowers on it now) with 500s with a high X dimension. It was a ***** to get out of the hole, but ran strong once up and hit 04 with stock 500s on the inner coastal off LA...so I would think shorties would help your top end. You asked this question on the Warlock Facebook page didn't you?