There are some considerations you need to examine. Is the car your daily driver? Actually, that isn't that important if you take it easy with the converter.
I just switched from a c-4 to a t-5. I wanted the fun associated with driving the t-5. I had a built c-4 (have, it's in the garage for when I blow this t-5 up), 2800 stall b&m converter, shift kit, reverse manual valve body, billet one piece input shaft, and aluminum driveshaft. Check my specs below to see my runs with it. I haven't made any runsd yet with the t-5, but it feels faster. 2nd gear feels like 1st in the c-4, third gear is second, and 4th is third. So, you can imagine, with 3.55's, you are reving like 2500 rpm on the highway. That part gets annoying after a while. while with the t-5, you are at like 1500 or so. you know what? find someone with a c-4, and go for a ride, see if you like how it feels. Also decide if you no longer wish to have the conrtrol you had with aq 5 speed. just my .02
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12.54 @ 110.90
1.62 60'
best with old car, will let you know once i finish the transfer to the new to me car
click here to see my car!