in my VW I got a gel cell, it is real light weight but has 450cranking amps. they make higher cranking amp lithium one's that weigh even less mine is under 6lbs, might be something to look into for weight reduction?
how about making a pure alcohol racer ? this stock block i4 run 6´ https://www.youtube.com/watch?v=Atjfrrpuwz8 using a vw engine. some of those vw engines is also compatible with hyabusa heads for insane revs.
This is going to come off as a stupid question but… You need a sequential transmission for the sequential shifter correct? I can't seem to remember when you replaced the tranny on this thing.