dogboy,
The 2 speed is noisy, not much fun to drive, and really lacks anything in the line of standing start take offs.
I changed out my 2 speed and put in a TH350. Everything is the same and bolts up with no modifications. Put a shift kit in it and can get the tires to squeel going into second with out much effort.
My engine is putting out about the same HP that you are planning to build. Not sure if you have a column or floor shift, but it makes no difference. You can change the 2 speed shifter on either to a 3 speed with a conversion kit from Shiftworks. Easy to do and works great.
Trust me a 3 speed auto is much more fun and a lot more perfomance than the 2 speed you currently have. If you do put in a 3.55 or steeper you will wish you had the 3 speed.
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