Hi Gang Still working (slowly) on the old Studebaker pickup... Got a question I am sure several of you will know.. I got a 9" ford rear end... Currently it has a 2.75 rear gear in it. I have a 350 Chevy motor, and will have a 700R4 ****** with overdrive. SO heres my question. What would be the proper rear gear to put in. I plan on putting on 16 or 17 inch wheels. I'd like for it to run about like my T-bird runs. That is about 75 mph at about 2000 rpm. SO what do ya think. I know my T-bird don't have 17" wheels... so I'm not sure how that will figure into it. I'm guessing it'll be in the 3.50 or 3.70 range... but I'm just guessing Also how do you figure (or adjust) the speedometer later on to get the right speed and it not be 'off'.
What is also important is the tire size/diameter. 750-16 are like 31" tall, 600-16" are only about 28" tall, so those 3", will make a huge difference as well. You basically need to know the tire diameter and transratio and then you can calculate your gears. I don't know how to calculate this, but someone here will.
OK.. someone will have to educate me... where I'm from.. or who I deal with... they don't speak about tires in a way of "700-16" or "600-16". We we discuss tire it's like 235-60-16.. kinda what I got in mind that or a 17" inch
I hear you, as an example, 700-16" are Bias Ply tires, 235-60-16 are radial tires. All you need to know is what the actual diameter of the tire is, you want to use.
Look at Richmond Gear site, plug in neccesary info into calculator and it should help determine was gears you want to go with. It'll ask for gear ratio, tire height and what trans (overdrive) etc.you have and give you RPM's.
27" tire, 700r4 OD 0.7, 2000 rpm, 76 mph 3.00 rear ratio 28" tire, etc., 77 mph 3.07 rear ratio 29" tire, etc., 76 mph 3.25 rear ratio 30" tire, etc., 75 mph 3.40 rear ratio 31" tire, etc., 76 mph 3.45 rear ratio
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