I replaced my TB on my 4.3 with a modded one. I think that hootus is there for emissions purposes & I think I read that it's supposed to help low speed torque or something but I can't swear to that. I didn't notice any ill effects after I replaced it. Actually my throttle would hang a bit before I replaced it(I think because of that hootus). It was quite a bit more responsive off idle afterwards but my 1/8 mile times didn't improve much at all.

I'll sell you mine if you want it. It has been polished,hootus removed, & throttle shafts halved all for improved flow. PM me if your interested and I'll send you some pics.