ok i called holley today and the answer i got was that we can use it for controlling fuel but we would have to have some other way of controlling spark/timing (msd DIS, etc)...so i guess ill be passing on this one....i was looking into the MS but here is my only problem...i asked a couple guys around where i live if they have ever tuned it and none of them have plus its so cheap in cost and it seems hard to believe that something that is supposed to work so good is so cheap...any input on that at all