As for the gears, 3.35 is the most you're gonna want. I'm N/A with a decent amount of power and my 1st get very little use I guess you can say. I'm in and out of it before you can say anything that comes to mind. My 2nd gear pulls like a bat outta hell, so the gearing is optimal. As for strength, anything is stronger than the stock 94-98 t-5's but the 99+ T-5D's are pretty stout.
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60' ~ 2.1, 1/8 ~ 9.61 @ 73.4mph
Living one day at a time!