10:5:1 compression?? Race car?? The 306 is reliable, and probably more reliable then the cobra. I have a 306, with 9:5:1 Compression. I have to run super. Does the AOD have a stall? If so is it a lock up or non lock up? With out a lock up you will have no OD, and that means, no with 4.10s you will be limited to around 50 mph. Its annoying as hell. I lost OD in my old AOD GT, and I had 4.10s. I was at close to 3k rpm at 50. It sounds like a nicely set up car though. If it was streetable, and you knew you had a OD, I would say do it. I love my fox. They have always been reliable to me.