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For fun driving on roads with low traffic volume, which transmission do you prefer?

  • Manual

    Votes: 30 83.3%
  • Automatic

    Votes: 6 16.7%
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I like it how it safes fuel and evey thing runs quieter in an OD. But since you are pissed off by shifting one more gear perhaps an automatic might be a good thing for you.
"row, row, row the boat..." if you get off shifting through all those gears all the time, go for it.... not everyone runs a road course or a drag race every time they drive.

ok then, why did i swap to a 5spd? because i thought it would be cool... well the "cool" wore off real quick in everyday driving. just another one of those things i've learned the hard way...

and, yeh, my Solstice is an automatic (as is my Enclave, Sebring, Smart, Caravan, Sierra, and motorhome). i drove a stick solstice before buying the automatic and my apparently improper grip on the shifter knob made it possible to inadvertently tune the radio when shifting to 3rd and 5th.

Bill
 

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How am I going to text and drive at the same time if I have to manually shift gears?
 

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Discussion Starter #63
In the old days an OD ratio was typically around 0.8, or a little longer. The MGs ran a dual ratio OD - it would only shift in when you were in 3rd or 4th, and the Triumphs even allowed it to operate in second. They were Laycock de Normanville OD units with isolator switches to prevent engagement in reverse, which would have damaged the one way clutch arrangements inside. It was much nice to be able to shift between 3rd and 3rd OD by extending a finger to flick a nearby switch than to have to pull a normal shift, but it was arguably heavier and certainly more complicated.

The loooong ratios of some American cars came about (as I was told) so that they could quote better fuel numbers on the prescribed circuits they had to run for EPA reasons - down around 0.6 was typical but it made a large step between top gear and OD.

I ran an OD in my race cars, but only so that I could enhance acceleration by using a lower diff ratio while retaining top speed by using the OD.
 

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Some seem to think that they have to defend their choice. Buy what you like, drive what you like and enjoy your ride. You aren't going to change anybody's opinion by telling them why you do what you do.
 
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In the old days an OD ratio was typically around 0.8, or a little longer. The MGs ran a dual ratio OD - it would only shift in when you were in 3rd or 4th, and the Triumphs even allowed it to operate in second. They were Laycock de Normanville OD units with isolator switches to prevent engagement in reverse, which would have damaged the one way clutch arrangements inside. It was much nice to be able to shift between 3rd and 3rd OD by extending a finger to flick a nearby switch than to have to pull a normal shift, but it was arguably heavier and certainly more complicated.

The loooong ratios of some American cars came about (as I was told) so that they could quote better fuel numbers on the prescribed circuits they had to run for EPA reasons - down around 0.6 was typical but it made a large step between top gear and OD.

I ran an OD in my race cars, but only so that I could enhance acceleration by using a lower diff ratio while retaining top speed by using the OD.
way back.... in the 50's and earlier, Borg Warner made a 3spd overdrive transmission that was actuated by a electric solenoid. if you used a switch to energize the solenoid you could have OD in all 3 gear; makes it a 6 spd... except you momentarily had to let up on the accelerator in order for the solenoid to do it's thing. kinda fun as a teenager, but it's practical use was simply as OD.

Bill
 

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I havent turned off the raido in a good while while shifting but....it does get muted a few times a month. if I had the $$ I wood go buy a auto gxp, either yeller or the same as what I have now a cold sliver..then try to find a steel sandy interior to go into it.
 

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Discussion Starter #68
If you want to avoid hitting the radio, but a DDM short shifter kit - it improves feel quite a bit and I don't think you'd still hit the radio.
 

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OD was named that because it was a secondary gear box attached to the output shaft on the transmission. It could be turned on and off either by a mechanical lever or via a button. Think of a 2 speed rear axle on a dump truck or semi truck. It functioned much in the same manner.

Over Drive means one thing. it takes less then one revolution of the input shaft to create 1 revolution of the output shaft. Under drive is the opposite of that. 4th gear in the Solstice is 1:1 both automatic and standard alike. 5th gear is an overgrive gear.

The ratios on the 6 speed (gear) manual GM T56 transmission are
2.66:1
1.78:1
1.30:1
1.00:1
0.80:1
0.63:1

and with the ford 10 speed automatic
4.696:1
2.985:1
2.146:1
1.769:1
1.520:1
1.275:1
1.000:1
0.854:1
0.689:1
0.636:1


The final gear in both transmissions is really close to one another and if the final drive was the same and the max RPM of the engine was the same both would achieve a really close top speed.
Now I would not want to to have to shift through 10 manual gears. in a race you would lose because of how many times power is being disconnected when driving a manual.

With performance is the thing you are looking for the ratios should be set so the RPM drop of the engine when shifting does does not drop the RPM's out of the power band when shifting near red line. When you have 2 transmissions like above where one has more gears then the other but the final ratio is the same the RPM's have to be looked at.


If you have a V8 with a red line of 5500 RPM's the power band is typically going to start at 4250 RPM's. This is 1250 RPM's total.

If you paired the stock manual transmission up to a V8 that has a red line of 5500 RPMs this would be what the RPM's are after a shift at 5500 RPMs

3315
3334
4015
4015
every single one is outside of the engines power band. This is not an ideal pairing of transmission to engine.


if you pair the same V8 to a T56 transmission which is a 6 speed.
3680
4017
4213
4400
4331

It is a much better pairing.

now pair that V8 to the ford 10 speed
3496
3954
4534
4726
4613
4314
4697
4437
5077

The benefits of a 10 speed transmission is the starting gear ratio. The vehicle is going to be able to move faster and easier out of the gate because of the ratio. The engine is not going to have to work as hard to move the same weight allowing the RPM's to get into the power band faster. More gears are better for vehicles that need to move weight because of the starting ratios. The most fuel efficient transmissions are CVT transmissions which do not have gears. CVT transmissions do not operate in a vehicles power band and can only get into the power band at high speeds. These are the worst transmissions for performance.
 
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