Question about 0verdrive and Drive....
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Question about 0verdrive and Drive.... I do my normal driving in (OD) and when i want more power - Friday thru Sunday - I put the shifter in (D). And I read here about locked and unlocked torque converters, and I got a question. When Im in (OD) is the torque converter in the locked position and when Im in (D) is the torque converter in unlocked position? Because I've noticed when I put the shifter in (D) the car responds very quickly, and is noticably faster, and Very fun to drive, especially in the freeway. And I'm here learning about torque converters. Help me out, thanks.
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well you have 4 gears i spose you can say, if you keep the motor strung out in 3 you will be in powerband more or less. D aka 3 also engine brakes so when you let off the gas it sorta slows down for ya.
The lockup is programmed in 3/4 by the tune. once you get a 'verter & cooler & shift kit & nitto's you'll probably want a tune done on your car to tweak the driveability.
you don't really get any more power if you use the gas pedal to make the pcm shift for yah
stock converter = boring as hell. throw a 3500 on there and you wont have to dick around with d/OD at all.
The lockup is programmed in 3/4 by the tune. once you get a 'verter & cooler & shift kit & nitto's you'll probably want a tune done on your car to tweak the driveability.
you don't really get any more power if you use the gas pedal to make the pcm shift for yah
stock converter = boring as hell. throw a 3500 on there and you wont have to dick around with d/OD at all.
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Originally Posted by samz28
well you have 4 gears i spose you can say, if you keep the motor strung out in 3 you will be in powerband more or less. D aka 3 also engine brakes so when you let off the gas it sorta slows down for ya.
The lockup is programmed in 3/4 by the tune. once you get a 'verter & cooler & shift kit & nitto's you'll probably want a tune done on your car to tweak the driveability.
you don't really get any more power if you use the gas pedal to make the pcm shift for yah
stock converter = boring as hell. throw a
The car feels faster though, when I force the pcm to shift.3500 on there and you wont have to dick around with d/OD at all.
The lockup is programmed in 3/4 by the tune. once you get a 'verter & cooler & shift kit & nitto's you'll probably want a tune done on your car to tweak the driveability.
you don't really get any more power if you use the gas pedal to make the pcm shift for yah
stock converter = boring as hell. throw a
The car feels faster though, when I force the pcm to shift.3500 on there and you wont have to dick around with d/OD at all.
I'll be saving up for a high stall, torque converter.
driving in 3rd or D will not hurt the transmission at any speed all the way up to the redline of the engine. I drive in third over 120 MPH at the track 
The coverter will lock up in third and fourth gear. If you want to see the coverter lock and unlock, drive on the freeway on level ground at a moderate speed, say 70. watch your tach. Then gently touch the brakes you will see your RPM raise a couple of hundred RPM. This is the clutch disinguaging. It will then lower after you let off the brake. The lockup will disingage off of the same sensor your brake lights and cruise control release works off of. The way a lockup coverter works is similar to the clutch in a manual in theory. when its unlocked at lower gear and speed the hydraulic turbine blades in the converter move the car, but allow for slippage. A high stall converter allows the car to slip into a higher rpm where the car will make more power to the wheels. When it locks up it is a solid connection just the same as a manual transmission
The coverter will lock up in third and fourth gear. If you want to see the coverter lock and unlock, drive on the freeway on level ground at a moderate speed, say 70. watch your tach. Then gently touch the brakes you will see your RPM raise a couple of hundred RPM. This is the clutch disinguaging. It will then lower after you let off the brake. The lockup will disingage off of the same sensor your brake lights and cruise control release works off of. The way a lockup coverter works is similar to the clutch in a manual in theory. when its unlocked at lower gear and speed the hydraulic turbine blades in the converter move the car, but allow for slippage. A high stall converter allows the car to slip into a higher rpm where the car will make more power to the wheels. When it locks up it is a solid connection just the same as a manual transmission
Last edited by koolrayz; Aug 29, 2004 at 07:59 AM.
Originally Posted by koolrayz
Then gently touch the brakes you will see your RPM raise a couple of hundred RPM. This is the clutch disinguaging.
I knew I'd seen what you are discribing, but by the time I'd look down it would steady out. 
Learn something new every day I guess. Thanks. 
You don't have to constantly leave it in D aka 3 or OD. If your cruzing on a friday night going 60 mph, knock it into OD, if some ricer comes along knock it down to 3 to have a little fun. Either way when you go wot the pcm will take care of you.
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From: Wichita KS / Rancho San Diego
I eliminated 3rd gear lock-up with tuning, and that makes the car much more flexible and responsive around town. When I want efficiency or for higher speeds, it's into OD.
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On The Tree
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Originally Posted by RevGTO
I eliminated 3rd gear lock-up with tuning, and that makes the car much more flexible and responsive around town. When I want efficiency or for higher speeds, it's into OD.
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Verdad Gallardo Joined: Nov 2003
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From: Wichita KS / Rancho San Diego
Well, I think it could be true for long periods especially at higher rpms ... I posted about it and several of our resident gurus said they had done it and it wouldn't hurt anything. I mostly use it trafffic below 40 where I'm on and off the throttle a lot, and locking/unlocking and engine bog would make for an unpleasant driving experience. I really like the flexibility and driveability this change made.
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For some reason shifting in OD and D occur at different RPM's. Meaning at WOT in D has netted higher shift points then OD. It has also put me into the limiter because of this. Why I dunno maybe someone can explain.
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All this good inof make me remember, one time I had the car on (D) and on a lonely road, I pressed the car really hard, no cars in front of me and had lots of room to run, then I noticed I could Not get past 120mph and I hit it to the floor and nothing more and so I tried to force downshift and nothing. Then I learn from this website that (D) is actually 3rd gear and the pcm Will Not allow the car to shift in 4th gear when in (D) -aka 3rd gear- and so it hit me, "when I read (D) is actually 3rd gear" and when in (OD) you can use the complete 4 gears and so of course in (D) I wasn't going to go any faster because Im only useing 3 gears and pcm didn't allow me to go to 4th while I was in (D), but I was worried for a while, why I wouldn't advance past 120mph, but now, I know why. Im really glad I came across this site, great site, great knowledgeable people, and Pro Stock John will take the time to liston to any question one may have and Nine Ball, all great people.
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From: SC
Originally Posted by 98LS1rocket
..but I was worried for a while, why I wouldn't advance past 120mph...
You may have been hitting the factory speed limiter.
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I tried to explain -but didn't do a good job-, when I put the a4 shifter into (D) I toped out at 120mph. And I was stumbled, why? But read here that (D) is 3rd gear, and if I want more mph, leave it in (OD), which I have yet to max out, the fasest I've dared to go was 152mph without maxing out.
On The Tree
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From: Texas
Huh???
Originally Posted by 98LS1rocket
I tried to explain -but didn't do a good job-, when I put the a4 shifter into (D) I toped out at 120mph. And I was stumbled, why? But read here that (D) is 3rd gear, and if I want more mph, leave it in (OD), which I have yet to max out, the fasest I've dared to go was 152mph without maxing out.
I agree with the post above, that you're probably just hitting the rev limiter.
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Are you sayin I could go past 120mph in 3rd gear? Because, like I mentioned in 3rd gear, no matter what I did the car would not go past 120mph, but now, I know to shift it into (OD) - 4th gear - to go more mph, at least with my car. Black 2001Vette, Nightmare, no offense taken, thanks.
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I forgot to mention, when this happened, all I looked at was the mph and not the rev limiter, so I was probably hitting the rev limiter, as Grayz mentioned.
ok maybe I've just lost it.. but here's what I recall being the shifter layout
P-R-D-3-2-1 .... Now when you guys say driving with the shifter in " D " it's in 3rd gear ?
Also, where on the shift-board
is " OD " ... I feel so dumb 
P-R-D-3-2-1 .... Now when you guys say driving with the shifter in " D " it's in 3rd gear ?
Also, where on the shift-board
is " OD " ... I feel so dumb