Drive or OD when at the track? I have been using 'D' at the track and I just seen the Colonels recommendation to keep it in OD, anyone doing this and what would be the differnece? TIA.

BTW, everyonce in a while, spraying or not, my 2-3 shift seems to take a little too long, not that snappy like the 1-2 which is the basis for this '?'.

Charlie.

 

Your shift takes longer probably cause of torque management. I put mine in D alot of people say OD so you dont hit the rev limiter but i have HPP3 so i dont hit it.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by sited12:
<strong> Your shift takes longer probably cause of torque management. I put mine in D alot of people say OD so you dont hit the rev limiter but i have HPP3 so i dont hit it. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Ditto ! <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> <img border="0" title="" alt="[Cool]" src="gr_images/icons/cool.gif" /> <img border="0" alt="[burn out]" title="" src="graemlins/gr_burnout.gif" /> <img border="0" alt="[driving]" title="" src="graemlins/gr_driving3.gif" />

 

From what I can tell, the shifts are a bit quicker in OD rather than D. I think this is why so many people (myself included) have noted hitting the rev limiter on the 2-3 shift in D but never hitting it in OD. This happens when the shift points are fairly close to the rev limiter. The shift takes just a grunt longer (possibly more slippage due to less pressure at the clutches?) and thus, the limiter is hit.

Try it both ways. I think you'll find the shifts to be a little quicker on the 2-3 shift with it in OD.

 

Now I wait in lay for Fried-day to test this out. Thanks for input guys.

Charlie.

 

If you are bracket racing you want 'D'. If you need to let off it will shift to 4th if you are in 'OD'.

 

When I am racing my A4 I have had better times when starting in #1 and I shift @ 5500 and the car shift itself @ 5900 and never hit the rev limiter in 2nd or 3rd. However, when I would take off in overdrive or drive the car shifts out too soon or bog out.

 

I have a Speed Inc 4L60E. I was told by the builder of this trans that it is better (for the trans) to be raced in 3rd than OD. I have noticed that the car shifts (upshift and downshift) much better in 3rd with my particular trans...

Colonel...what's your take on that? I've actually heard in more than one place (including my trans builder) that 3rd is prefered for racing as it's better for the trans. Do you feel differently? I'd like to get your thoughts on this...

I've also found that my TC clutch lock-up seems to be stronger in 3rd than OD with this trans. Any thoughts on that? Thanks for any insight you can give... <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

PS. My trans is vacuum modulated if that makes any difference...

 

I have heard the tranny is weaker in OD than in drive. Just cant remember exactly what part of the tranny it is. So when i beat on my car i stick it in D.

 

I like the way my car feels when it is in D, like it was said earlier though when in D I hit the limiter. So when I am lined up I put it in OD. But yes I do agree it feels much stronger in D. The rev limiter is the determaning factor in my case. I suggest you use D if your car doesn't hit the limiter. That's just my take.

 

"Colonel...what's your take on that? I've actually heard in more than one place (including my trans builder) that 3rd is prefered for racing as it's better for the trans. Do you feel differently? I'd like to get your thoughts on this..."

I don't know about the vacume modulated stuff so let's stick to what most of us have.

As we all know, you're more likely to hit the rev limiter in D than in OD, right?....RIGHT! Why is that? Is the PCM initiating the shift earlier with the selector in OD? I think the programming is set just as it is no matter if the selector is in OD or D. It's set by RPM and MPH. I wouldn't think these values change by selector position. So then, what could be the explanation? More clutch slippage and/or a slower shift. I think the pressure the clutches see might be lower in D and/or the speed at which the releasing and applying takes place is slower in D. In either case, clutch life will be shortened with a longer, sloppier shift.

You folks finding quicker times with the selector in D don't have your shift points set high enough for the 2-3 shift to time out right with it in OD.

I've heard since I was a kid from every Joe Bob and Billy Ray that D was the "racin' gear!" <img border="0" alt="[jester]" title="" src="graemlins/gr_jest.gif" /> Maybe for some trannys but for the 4L60-E I say <img border="0" alt="[bullshit]" title="" src="graemlins/gr_bs.gif" />

I just talked to my tranny builder and he said that he can't see of any physical reason that the 2-3 shift should be any different in D than in OD (he didn't sound real sure so the posibility still remains.) He said if there's any difference, he thinks it would have to be in the programming.

And the fact still remains that MANY of us note higher RPMS during the 2-3 shift if it's in D. I wouldn't think it's PCM controlled line pressure because that is set to %100 at WOT and I would assume that this goes for D and OD...but then again, who knows?

To sum up my thoughts...

The 2-3 shift reaches higher RPMs with the selector in D. I don't think the PCM initiates the 2-3 shift earlier with the selector in OD so that leaves only the posibility of a shift with more slippage with the selector in D (sure seems that way in my car.) This I don't want so mine will be raced in OD. <img border="0" alt="[burn out]" title="" src="graemlins/gr_burnout.gif" />

 

Like Colonel said I used to hit the rev limiter a lot in my car with it in D, but rarely hit it when it's in O/D. That's from my experience.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Colonel:
<strong> "Colonel...what's your take on that? I've actually heard in more than one place (including my trans builder) that 3rd is prefered for racing as it's better for the trans. Do you feel differently? I'd like to get your thoughts on this..."

I don't know about the vacume modulated stuff so let's stick to what most of us have.

As we all know, you're more likely to hit the rev limiter in D than in OD, right?....RIGHT! Why is that? Is the PCM initiating the shift earlier with the selector in OD? I think the programming is set just as it is no matter if the selector is in OD or D. It's set by RPM and MPH. I wouldn't think these values change by selector position. So then, what could be the explanation? More clutch slippage and/or a slower shift. I think the pressure the clutches see might be lower in D and/or the speed at which the releasing and applying takes place is slower in D. In either case, clutch life will be shortened with a longer, sloppier shift.

You folks finding quicker times with the selector in D don't have your shift points set high enough for the 2-3 shift to time out right with it in OD.

I've heard since I was a kid from every Joe Bob and Billy Ray that D was the "racin' gear!" <img border="0" alt="[jester]" title="" src="graemlins/gr_jest.gif" /> Maybe for some trannys but for the 4L60-E I say <img border="0" alt="[bullshit]" title="" src="graemlins/gr_bs.gif" />

I just talked to my tranny builder and he said that he can't see of any physical reason that the 2-3 shift should be any different in D than in OD (he didn't sound real sure so the posibility still remains.) He said if there's any difference, he thinks it would have to be in the programming.

And the fact still remains that MANY of us note higher RPMS during the 2-3 shift if it's in D. I wouldn't think it's PCM controlled line pressure because that is set to %100 at WOT and I would assume that this goes for D and OD...but then again, who knows?

To sum up my thoughts...

The 2-3 shift reaches higher RPMs with the selector in D. I don't think the PCM initiates the 2-3 shift earlier with the selector in OD so that leaves only the posibility of a shift with more slippage with the selector in D (sure seems that way in my car.) This I don't want so mine will be raced in OD. <img border="0" alt="[burn out]" title="" src="graemlins/gr_burnout.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Somoe good info here... <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

I still wonder why I was told to keep it in 3rd. Maybe the rules change when you go to vacuum modulation. Honestly, the upshifts, downshifts, and TC lock-up all feel better/stronger in 3rd with my trans. Really odd that there would be any difference really. They should be the same... <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />

 

I'm still fairly new at this also and have problems hitting the rev limiter in third. I have an HPP3. Where should I be setting the shift points and rev limiter at? Thanks

 

Oh by the way I'm going to try what the Col. says next time at the track.

 

I wonder if this hitting the limiter on the 2-3 shift in 3rd is an '01 and up issue? Neither my '99 Z or my '00 WS6 ever had any issues with hitting the limiter on the 2-3 in 3rd; from when they were totally stock up to mods and a built trans <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" /> Wonder if it is a PCM issue??

I think the biggest benifit I see to using 3rd is that I get quicker downshifts. Seems that when I floor it in OD to get a downshift to 1st, it'll go back to third first, then downshift to 1st. If I just floor it in 3rd it'll go right back to 1st real quick. There is some lag time waiting for a downshift to 1st in OD with my trans...

Also, I've noticed that I get an earlier TC lock-up in 3rd. Usually 31mph or so vs 36 or so in OD. Very odd...

 

This is a dumb question but what is OD ?
I only have 1,2,3,D,N,R,P in my trans ? <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Fierce-LS1:
<strong> This is a dumb question but what is OD ?
I only have 1,2,3,D,N,R,P in my trans ? <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">OD = Over Drive. In the case of 1-2-3-D, the "D" actually = OD.

 

My car is a 98 so it's not a 01-up problem. I wonder myself if it's not a PCM issue. I don't see what the tranny thinks the difference is between 3 and O/D so in my opinion it would be a PCM issue.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Snake Skinner:
<strong> My car is a 98 so it's not a 01-up problem. I wonder myself if it's not a PCM issue. I don't see what the tranny thinks the difference is between 3 and O/D so in my opinion it would be a PCM issue. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I agree with this. Just like some PCMs freak out applying massive torque management after a big TC install and other's just don't, I think this is a similar tyoe of issue. Some PCMs do it and some don't. I personally have seen no difference between 3rd and OD WOT shift rpms on the 2-3 shift. Biggest difference I've seen is that 3rd seems to downshift quicker (very noticeable) to 1st and TC lock-up is quicker and stronger in 3rd. My car might not be the best comparison though as I have both custom tuning and a vacuum modulated trans. Still though, I don't think it's an internal trans issue.