Pinto Car Club of America

What gears would be the best in just everyday traveling? I'm thing about rebuilding the 8" rear end from the Mustang I got to put in the pinto.

Tony: For the early cars yes, I agree. For the later ones 2.79 to 3.18 are more common.

Bean: It would depend on what you want to do with the car. If you DON'T care about how fast you can get up to speed, then go 2.79 to 3.0. If you want good take off power AND good mileage, go somewhere in the middle like 3.0 to 3.18. If you want take off power then go 3.40 and up.

Keep in mind your engine (power) and tire size need to be looked at too.


Bill

I think a 3:40 gear would be best ( my opinion ) due to the gas milage factor and you still get good acceleration. Tire size will affect this so if you want a freeway flier then opt for some tall rubber ( i.e. up to 28" ) middle of the road would be about 26" and for better acceleration 24 ". Of course I don't know anything about your car so I am basing this on one of my cars.

Thank got the info I wanted.

I agree that it is very important to factor in the tire size (in addition to engine and trans ratios) when considering rear gears.  When I was crunching numbers for my Turbo Pinto (primarily for street driving) I had to consider that the T/C T-5 trans has a first gear right around 4.00.  So, I figured a rear ratio around 3.25 would be ideal.  The problem is I have been told that that is a rare ratio to be found in an existing 8" rear (I understand that the ratio is available from the aftermarket).

After a 6 month search for an 8" I finally found two in one day and had the option of a 3.55 or a 3.00.  I opted for the 3.00 based on my intended driving (street), the price of gas, the fact the the T/C outweighed the Pinto by half a ton (1,000 lb's) and the tire sizes that I was able to consider with that ratio (short 15" to tall 13").

Just as a reference point the T/C trans 4.00 first gear with 3.00 rear gears has the identical multiplication as a Mustang trans 3.35 first gear with the 3.55 rear gears - in first and second gear (only).  After that the T/C trans with a 3.00 rear does spread out some.

My goal was to spend as little as possible (no aftermarket gears), use the T/C, T-5 trans (again to save money) and fiddle the (factory available) 8" rear ratio and tire size to deal with the stump puller first and the overdrive fifth. If money was no object I would probably change the rear and trans for more ideal ratios. Unfortunately money is a issue and I'm trying to make the most of what is probably too large of a gear spread for the weight of my Pinto.  Before I finalize my tire size I'll test drive different sizes and and have to decide on too low a first, too high a fifth or a compromise on both ends and a more drivable middle.

Anyway, before you go out and get gears you have to consider EVERYTHING involved.  I often laugh when I see guys go out and get drag strip ratios with their street tires.  When guys run drag strip ratios they usually do so with rather tall slicks.   The "effective ratio" of the drag car might well be close to what the street car is already at with the factory ratio and shorter street tires.  Do the math - then decide.
Tom