what the best way to race an auto
#4
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How does this work? I've seen people say there's
something different about D/OD shifting, seen it
both ways, but never come across anything in the
tuning tables or observed it myself. What's the
mechanism and what should I look for, by way of
feel or result?
something different about D/OD shifting, seen it
both ways, but never come across anything in the
tuning tables or observed it myself. What's the
mechanism and what should I look for, by way of
feel or result?
#6
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Originally Posted by jimmyblue
How does this work? I've seen people say there's
something different about D/OD shifting, seen it
both ways, but never come across anything in the
tuning tables or observed it myself. What's the
mechanism and what should I look for, by way of
feel or result?
something different about D/OD shifting, seen it
both ways, but never come across anything in the
tuning tables or observed it myself. What's the
mechanism and what should I look for, by way of
feel or result?
Ed
#7
I leave mine in drive(3rd), as I do not want to ever end up in my overdriven 4th gear, not to mention the 1:1 3rd gear helps slow my car down after the lift. I just finished having to rebuild my tranny(for the fourth time), because during a top-end race with a Ferrari, I ran out of cam and was forced into my overdriven 4th gear at 6750 rpms. Almost immediately, my DIC lights came on to warn of *HIGH TRANS TEMPS*. That was at around 135 mph. Well, fortunately, the Ferrari who was finally starting to gain on the top-end until I shifted to 4th, got cold feet and backed off, not knowing I was going to have to get off it anyways due to a tranny temp of 264'.
Even though I immediately went to my tranny shop and had them flush and change the fluids, it was already too late. The 4th gear clutches were gone, and my band was burned enough to replace. This was with a level 4 tranny, and a cooler, and LS1 edit!I can promise you, I will never shift into fourth again, after that expensive lesson, and being in drive, is my insurance!
What was really confusing, is that I had no slippage in the usual 2-3 shift. Only fourth was freewheeling on me. In past rebuilds, I was used to the common 2-3 shift hitting the rev-limiter, cause the 3/4 clutch pak was burned up. Not this time...I wasn't expecting that! Lesson learned.
Even though I immediately went to my tranny shop and had them flush and change the fluids, it was already too late. The 4th gear clutches were gone, and my band was burned enough to replace. This was with a level 4 tranny, and a cooler, and LS1 edit!I can promise you, I will never shift into fourth again, after that expensive lesson, and being in drive, is my insurance!
What was really confusing, is that I had no slippage in the usual 2-3 shift. Only fourth was freewheeling on me. In past rebuilds, I was used to the common 2-3 shift hitting the rev-limiter, cause the 3/4 clutch pak was burned up. Not this time...I wasn't expecting that! Lesson learned.
Last edited by black 2001Vette,Nightmare; 03-07-2006 at 08:05 PM.
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Originally Posted by Pro Built Automatics
If you are going to let it shift automaticly, leave it in overdrive as this will help the 2-3 WOT shift.
Could you elaborate a little? I have been curious about this also. Some of us don't want to go into 4th. Also I have read that from a roll it's better to drop to 3rd first as doing a downshift from 4th (OD) to 2nd is bad for the transmission. So we don't want to go into 4th at WOT, and we don't want to go from 4th -> 2nd, however we get more holding power if the transmission is left in "OD" ("D" for the Pontiacs)?
So what is the best option?
#10
I have a 98SS and I have race in "D" and "OD" and found that the best for is "D" It seems to have better take off and all around power but you will have to just play with it and find out which you like better.
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Originally Posted by BlackHawk T/A
Right but that wasn't my question...
So, bump.
So, bump.
Originally Posted by MRZ28
Is it better to manual shift the 4l60e or to just leave it in drive when racing?
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Well I shift my car manually at 6000(I shift it at 55 or 5600 and it engages at 6000). I've heard its bad, ive heard its ok. I know it is quicker by a good half to a tenth in the quarter(I tried both same day). I'm thinking about bumping up my shift points in the computer and letting it shift itself, but will it make it to 6k?
#14
Put it in overdrive (D)...best thing to do....i was racing a vette once, a grand sport, and did the whole manual thing. Dammm 1st was a good kick, and i had no problem going into 2nd. but when going into 3rd or D, i messed up. The whole race i was winning and excited, i was the underdog, haha, but i was distracted and shifted to late and bounced off the rev limiter. I lost and learned the hard way. Keep it in (D) and youll be fine.
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Originally Posted by Pro Built Automatics
With the 4L60E, and you are going to "drag race" it, leave it in OD. This will prevent the overrun clutch assembly from coming on, especially on the 2-3 shift where you need all the oil going to the 3-4 clutches on a WOT shift, and not to the overrun setup also. Dyno tests have shown this to be the best way of doing this with the least amount of problems. A 2-3 flare at WOT in the "D" position, and the flare is not happening in the OD position is indicative of not enough oil going to the 3-4 clutches. This is only "one" of the good reasons why the 3-4 clutch pack will live longer when you leave it in the OD position when drag racing it.
#16
Originally Posted by ZTwentyAteU
Well I shift my car manually at 6000(I shift it at 55 or 5600 and it engages at 6000). I've heard its bad, ive heard its ok. I know it is quicker by a good half to a tenth in the quarter(I tried both same day). I'm thinking about bumping up my shift points in the computer and letting it shift itself, but will it make it to 6k?
I have my shift points set at a little under 6600... so you can set your shift points north of 6000 and it should be fine.