Possible stupid question about Overdrive
01-04-2008, 07:00 PM
#2
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Join Date: Oct 2007
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Posts: 55
RE: Possible stupid question about Overdrive
I am guessing this is an auto.
It should not matter, as your transmission will downshift to whatever the maximum gear it can use without overrevving. In practice, turning overdrive off leaves you in 4th gear. So if you get on it, you have one less ratio to drop before power is applied. So, yes, if you are "racing" (in whatever form that might be), leave overdrive off.
It should not matter, as your transmission will downshift to whatever the maximum gear it can use without overrevving. In practice, turning overdrive off leaves you in 4th gear. So if you get on it, you have one less ratio to drop before power is applied. So, yes, if you are "racing" (in whatever form that might be), leave overdrive off.
01-04-2008, 07:17 PM
#3
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Join Date: Jan 2008
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Posts: 40
RE: Possible stupid question about Overdrive
ORIGINAL: gas_meet_foot
I am guessing this is an auto.
It should not matter, as your transmission will downshift to whatever the maximum gear it can use without overrevving. In practice, turning overdrive off leaves you in 4th gear. So if you get on it, you have one less ratio to drop before power is applied. So, yes, if you are "racing" (in whatever form that might be), leave overdrive off.
I am guessing this is an auto.
It should not matter, as your transmission will downshift to whatever the maximum gear it can use without overrevving. In practice, turning overdrive off leaves you in 4th gear. So if you get on it, you have one less ratio to drop before power is applied. So, yes, if you are "racing" (in whatever form that might be), leave overdrive off.
I have an XCAL 3 on the way though which is supposed to help some of the downfalls of the Automatic. I figured that it would add a little extra lag to transfer out of overdrive when it's on. Thanks
01-04-2008, 07:18 PM
#4
5th Gear Member
Join Date: Mar 2007
Location: Deep in the <3 of Tx
Posts: 3,925
RE: Possible stupid question about Overdrive
I don't think it would be bad to leave it on as I don't think the shift into 5th (OD) is a synchronous shift (I could be wrong). What is more troubling is the shifting from 2nd to 3rd and from 3rd to 4th. The reason is those shifts are synchronous shifts. The problem with that is if you're applying high power levels (like at WOT for example) you can have an rpm flare in the middle of the shift. This flare is a shock to the tranny and could damage it if the power level is high enough (usually if you're blown for sure).
This is the bad thing about the 5R55S in the 05 and up mustangs. The older auto, 4R70W (or 4R75W in 04), only did a sync shift going into 4th (OD), but since with that tranny, you usually turn off OD when racing so a WOT shift into 4 (OD) wouldn't happen.
I'm getting more and more scared of this new Auto the more I read about it. Sure having the extra gear closes the gap in performance vs the manual, but it seems to be weaker than the older Auto. Another reason why it's weaker other than the two sync shift is that it's smaller which could mean it's not as heafty at high HP/TQ ratings (probably why FRPP doesn't have an Auto option for the 500HP Whipple).
People say you can run a lot of HP from a blower in the new Auto if the tune is right, but that scares me. Now I have to have faith in the tuner that he's doing the right thing for the auto. This auto is seeming to me, more trouble than it's worth for high HP. Sure traffic is better with one but so what.
BTW, I got my info from here: http://www.alternativeauto.com/misc/r-and-d-gt.html
This is the bad thing about the 5R55S in the 05 and up mustangs. The older auto, 4R70W (or 4R75W in 04), only did a sync shift going into 4th (OD), but since with that tranny, you usually turn off OD when racing so a WOT shift into 4 (OD) wouldn't happen.
I'm getting more and more scared of this new Auto the more I read about it. Sure having the extra gear closes the gap in performance vs the manual, but it seems to be weaker than the older Auto. Another reason why it's weaker other than the two sync shift is that it's smaller which could mean it's not as heafty at high HP/TQ ratings (probably why FRPP doesn't have an Auto option for the 500HP Whipple).
People say you can run a lot of HP from a blower in the new Auto if the tune is right, but that scares me. Now I have to have faith in the tuner that he's doing the right thing for the auto. This auto is seeming to me, more trouble than it's worth for high HP. Sure traffic is better with one but so what.
BTW, I got my info from here: http://www.alternativeauto.com/misc/r-and-d-gt.html
01-04-2008, 07:55 PM
#7
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RE: Possible stupid question about Overdrive
ORIGINAL: howarmat
take it off....it will shift on you at the track limiting you power i believe.
take it off....it will shift on you at the track limiting you power i believe.
I'm not sure it will assuming you keep it at WOT the whole time. From my experience going WOT from 1st all the way to 5th, it will only shift into 5th when you hit redline (or pretty darn close to it anyway) in 4th which seems like a reasonable thing to do to gain more speed.
01-04-2008, 08:18 PM
#9
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Join Date: Mar 2007
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RE: Possible stupid question about Overdrive
ORIGINAL: killbee
Leave it off, if you have to back pedal any at all it will shift on you killing your top end pull.
Leave it off, if you have to back pedal any at all it will shift on you killing your top end pull.
You know you're totally right. I did not think of that.
Ok so the verdict is in....turn it off.