I think you are going to be pleasantly surprised. Even with tight converter and full exhaust the only way you're gonna run 11.8 is if you get absolutely no traction. I ran a combo just like yours with full exhaust 3k converter in all steel duster with cage. Only difference is I had a 248@050 solid roller. Eventually got down to 11.0s.@122 and that was with a lusy 1.65 sixty foot.