I used a 100" at first, after a couple of months the belt had stretched to
limit of the tensioner - I switched to a 99.5" Gatorback, # 4060995 -
it was tight going on, but good now
I would use a shorter belt. On my 96 the belt has stretched to max on tensioner. I have my home made TM set at about 12 peak, and I have not coded yet. It will run about 10 on hard acceleration, and 4-5 down the road.