3rdGenIrocZ

So i got a new 350 and the stock engine was a 305, and the fastest i can get it to go is around 145-50 and was wondering what the best tranny would be for the most performance? i got a 700r4 the stock tranny

performabuilt

While up grading the trans to a better built version might not be a bad idea,
Another trans wont make you go faster particularly on the top end now the addition of a built trans and a stall converter can do wonders on the bottom endBut 145-150 for your car on the top is perty fast IMO

ATX-Iroc

they sell a kit so you can shift to 4th at wot. or you can get numerically lower rear end gears. or you can swap in a six speed.

AlkyIROC

Depends what your demands are for performance.

For top speed on the highway, something with a couple of overdrives like a T56 plus some highway gears in the diff like 2.77. It'll be a real slug off the line but will have great top speed.

For straight line acceleration, a powerglide is the lightest and uses up the least amount of power but a deep gear in the diff is required to compensate for the high first gear ratio.

The 200-4R is a better choice than the 700R4. It's stronger and has a better gear ratio.

My car is geared for 1/4 mile racing. Using a powerglide, 4.86 gears and a 32" tall tire, I'm maxed out as I cross the finish line and I'm only doing 144 MPH but I've also reached that speed in less than 10 seconds.