good choice on the 3.73's if your sure your gonna do the T-5 swap eventually. Thats what I was debating when I bought my gears, because I knew that I wanted to do the swap but wasnt sure when or if it was within my price range.
Your right the PI converter is very expensive, but if you want to be competitive then you have to buy quality parts. Do you think Billy Glidden buy's parts for his Pro 5.0 car at autozone?
I ended up doing the whole T5 swap for CHEAPER than just the PI converter. Much cheaper when you factor in the money that I got for selling the AOD. I spent about $600 for parts (found a good cheap used T5) and sold the AOD for $425 so I made out pretty well. By far the best $175 i've ever spent
Actually I think you would be very competitive with the T-5 cars with a converter and some gears. I was ripping up 5-speed cars with mine with the stock converter. My stock headed/stock cammed/stock intaked/stock weight/ AOD went a best of
13.99@101.xx, not too shabby for a car that you will NEVER miss a shift in (nice when your street racing too

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good idea on waiting and doing it right. It sucks to have to do things twice. Good luck