OK ... I've taken the 422 Iron block out, moved the the 4.125 crank over to the LS7, purchased Diamond Pistions, three-angle valve job LS7 Heads with stainless steel valves, etc, etc ... and just got an LS7 intake. Upgrading the injectors to 80# (from the Siemens 55#'ers) and now I'm at the decision-making time on throttle body and MAF.

For centrifugal FI, does it matter a lot beteen the 90mm and 100mm MAF? Particularly since the stock intake and throttlebody are 90mm?

Also, since my tune is for the 75 mm MAF that came with my Trans Am (actually, an 80mm MAF on it right now), are there any tunes I can start from or import MAF for if I cnage from my stock MAF? Are there still huge hurdles to jump for a 1998 computer when changing to a larger MAF?

I've been out of the loop for quite a while and would appreciate any help, including .tun's to look at.

Thanks!