Toploader 4-speed manual transmissions: wide ratio versus close ratio: what does this mean ? Can somebody post a fairly complete explanation of these two terms ? When would you want to have a close ratio transmission and when would you want a wide ratio ?
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With close-ratio units, the gear ratio's for each gear are alittle closer together meaning this keeps the engine closer in its power band after each shift. IIRR, First gear is usually a little taller, 3rd is a little lower. This makes great for a road race application and as a daily street driver I especially like it.
Wide-ratio is great when your engine has a lot of torque (which all the 289's do- around 300lbs IIRR). This is typically better for drag racing type events since 1st gear (IIRR) is a little lower. Works fine for a daily driver also.
In addition to beachkid's excellent response, with the wide ratio, you will have sort of a poor man's overdrive. A wide ratio 4 spd with a 3.25 axle ratio will have about the same over all final srive ratio as a close ratio 4 spd with 3.50 axle ratio in 1st gear but will a more relaxed cruise in 4th, getting slightly better gas milage.
I have a close ratio 4 speed (not a toploader) in my '66 GT & a wide ratio 4 speed (toploader) in my '70 Boss clone. I much prefer the wide ratio 4 speed. With the close ratio you are constantly shifting, downshifting etc.. If you are choosing between the two what you should do is try to drive a couple of cars & get a feel for the difference. Good luck
That's absolutely right! I said over all final drive ratio in 1st. Meaning multiplying 1st gear ratio by axle ratio. A wide ratio box has a 1st gear, IIRC 2.73 and a close box is 2.42 IIRC. Multiply 2.73 X 3.25 = 8.87:1 Multiply 2.42 X 3.50 = 8.47:1
So you can see that by running a wide ratio with a 3.25 axle, you'll have a lower final drive ratio, meaning you'll pull away from a stop a lot easier. Then in 4th, you'll have a 3.25 vs 3.50 or about 11% lower rpms!
I just did a conversion on my toploader from a narrow to a wide ratio. I had a 3.0 rear and changed it to a 3,5 track lock. With my 351w whitch has gobbs of tourque it works great. Before first gear was way to tall. Now it comes out of the hole really well and the street cruise rpm is acceptable. In hind sight (20\20) I should have gone with a 3.25 rear gear. I still have the parts that I took out If anyone wants to reverse the conversion.
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