transmission help

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justme

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i found a friend who has a stort tail od trans, it has a 3.09 first gear and it also has a 5" throw out bearing colar, is that all right for a /6 street car ? is the 3.09 too high of a first gear? can i use that colar on the throw out bearing? will it work in a street car? is it the right one to use?
 
AS long as you get a OD bell for the slanty it will work just fine.
 
Some of the O/D bells have a 4.8" hole. You can use those as well, but you will need to have it machined, or you can get a 4.8" input bearing retainer. They are both on the same bolt pattern and will bolt up.

The short answer is yes. I it will work great for a slant six street car.

All O/D 833 transmissions have a 3.09 first gear. The idea behind the 3.09 first gear and O/D final is to make the 833 more useful in street application.

What the 3.09 gear sucks at, is launching the car from a high RPM. That's why the high performance A-833 transmissions had much taller first gears.

The 3.09 is made for walking speeds. It keeps the operator from having to feather the clutch a lot, in stop and go traffic, so it can make more use of idle and just off idle throttle position torque. Way easier on your feet.

The one thing I would suggest doing is going with a 3.55:1 or higher rear axle ratio. They did outfit them behind 3.21 gears, but I wouldn't go any taller than that. 3.55-3.91 range is ideal.
 
The 3.09 first gear goes nice with a slant 6, what sucks is when you grab second gear, that's when you realize that your only driving a slant 6. Having a 3.55 or 3.21 rear with 25" tall tires and an O.D. trans is nice well balanced combo for a daily driver, the low first gear gives you a good launch and the O.D. keeps the rpm down a 65 mph.
 
FYI........The ratios are; 3.09...1.67...1.00....73ish, I think. The splits are..54%,60%,and 73%..So whatever you shift your slanti at, the RPMs will drop down to those percents. eg; if you you shift out at 3600, then it will drop in at; 54%=1944:60%=2160,and 73%=2628. So your engine better be able to pull these (it can), but acceleration will suffer..... Unless you put a pump on it, in which case these ratios might even be an advantage. Just dont put too much power down in OD, its for cruising only.The OD mainshaft gear is very small( 23 or 24 teeth) and therefore easily overloaded. I broke 2 of them at part throttle with a hot-street 360. Your slant should never break one NA.The fun-factor of this combo depends very much on the correct-for-you rear gear selection.Too high and you run out of gear real quick. Too low and she may not pull OD willingly. For instance;3.09low x 3.91diff = 12.08 starter gear.Sounds great, til you shift at 4000rpm/24mph and are faced with2177rpm in 2nd which now has to pull to 4000rpm/44mph.Thats a long pull for the slanti. Then you shift into 3rd ratio 1.00. Rpm drops to 2400 and has to pull pretty much all the way to cruising speed.Say you take it to 4000rpm again. this would be 73mph.Thats a really long pull. Now you drop it into OD which being 2920rpm, Perhaps a little buzzy. So say you pull 3rd-direct to 65mph. still a long pull but OD is now about 2600. For me, these ratios just dont play well with slants. You may be happy, idk. The numbers move around some with alternate diff ratios but the percents do not. You can trade acceleration in 1st gear for cruising rpm in OD, but you cant do much with the long pulls. well there is one thing; GV(.78) gear splitter. Now yur talkin. The GVod splits these pretty nicely. I know. I have one. I have run it with 4.30s, 3.91s, 3.55s and 4.88s. Do the math;awesome; 7 useable gears 3 thrown shifts.Wide ratios for lazy plodding,tight ratios to keep her on the pipe. And 4.3diffx.73ODx.78GVOD=2.78 cruise gear! It loses its appeal as a splitter somewhat with higher power levels tho.With a hi-po 318 it was awesome. Now, behind my 360, I installed a 3.09-direct 4th 4 spd with the GV and mostly just use it as an OD. Ratios are; 3.09, 1.92, 1.42, 1.00, and.78GVod. Pretty neat.
 
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