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How to shift a Auto for Drag?????

Old Jul 8, 2007 | 10:37 PM
  #21  
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Originally Posted by BlackHawk T/A
FLT told me my level 4 would handle that just fine.
but the person i was talking to doesn't have an FLT level 4...and it's still not a good idea, regardless.

Originally Posted by BlackHawk T/A
Unless you really go over 125mph I wouldn't worry about going into 4th gear. For me OD will downshift a lot faster - going from 3rd gear gets me a big delay. Therefore the car stays in OD always. Plus it just feels a lot more solid. When I go WOT from 3rd gear, not only do I get a big delay, but something just doesn't feel right.
the thread is about drag racing...

but if you're gonna roll race, i would stomp it in OD and when it downshifts, throw it into 3/D. i prefer to put it into 3/D when i'm cruising locked up. it's not great to go from locked-up fourth gear into 2nd...at least i would assume that's true.

Originally Posted by BlackHawk T/A
Actually, there are manual valve bodies that do not take away the transmissions ability to still shift itself when left in drive. And a vacuum modulator only deals with line pressure - it removes the PCM's control of line pressure and leaves it up to vacuum pressure only. It does nothing to the shifts.
so delete the electronic solenoid that tells your trans went to shift. when people do that, they pair it with a vacuum modulator from what i've seen.
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Old Jul 9, 2007 | 08:48 AM
  #22  
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When racing from a roll I noticed a big dif. having the car in 1st gear from 30mph than having it in D and just stepping on the gas, because it doesn't take any time to downshift it's already there and it move's out hard, but I had no idea it was that bad for the tranny...now I know I appreciate the advice here, I wish I had read this sooner because I have been manually shifting a lot lately anytime I find a race from a roll, I'd bring down the gears and putting it into first at around 30mph never feels to good, it catch's really hard, now I'm worried I've been putting such a hurting on the tranny all this time.


Would a torque converter fix this and make it much easier and faster to shift without needing to start in 1st gear from a roll race from around 30mph.
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Old Jul 9, 2007 | 10:01 AM
  #23  
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Originally Posted by jimmy169
Would a torque converter fix this and make it much easier and faster to shift without needing to start in 1st gear from a roll race from around 30mph.
No it won't. But get one anyway

A higher stall will make you faster from a roll by flashing you to a rpm that makes more power then the stock 1800 converter. It'll also give you a higher shift extension to help keep you in the powerband. It'll even greatly reduce the dreaded "dead spot".

But unfortunately the transmission will still take that split second delay between flooring the gas and pinning you back in your seat. And it is VERY bad for the 4L60E to downshift manually. If you want to shift yourself then either get a M6 or TH400 with MVB. Otherwise the smartest thing is just to leave it in OD and let the transmission shift for you.

You can still roll race you just need to remember a few things. One is stay out of the dead spot. If I were to roll race with 3.23 gears then I would insist on a 20-30 mph start OR a 55-65 mph start. 31-50ish is the dead spot. Second is to time your launch. If you go on three honks then anticipate the third honk so that you hit the gas just before it. Then by the time the third honk happens the delay is over and you are hitting the WOT with perfect timing. It's the same idea as leaving on the third yellow light at the track instead of on green.
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Old Jul 9, 2007 | 10:13 AM
  #24  
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thanks a lot for the heads up, aspecially the deadspot i didn't know it was 31-50, that does make a lot of sense. I won't be manually shifting the car again it's not worth the risk.
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Old Jul 9, 2007 | 07:19 PM
  #25  
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Originally Posted by ChocoTaco369
so delete the electronic solenoid that tells your trans went to shift. when people do that, they pair it with a vacuum modulator from what i've seen.
From what you've seen? Who is building a MVB and manually shifting a 4L60E instead of a TH350-400?
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Old Jan 27, 2008 | 12:29 PM
  #26  
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Originally Posted by darrensls1
Second is to time your launch. If you go on three honks then anticipate the third honk so that you hit the gas just before it. Then by the time the third honk happens the delay is over and you are hitting the WOT with perfect timing. It's the same idea as leaving on the third yellow light at the track instead of on green.
i do that, i was racing a blown foxbody and obviously he knew my tricks, he took off as soon as he heard my exhaust get louder, about .3-.5 seconds later the car downshifts, i take off...and lose...
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Old Jan 27, 2008 | 01:15 PM
  #27  
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Someone should sticky this with the number of times this question comes up: let it shift itself. Its called the 4L60*E* for a reason, not TH400. You guys have some crappy running transmissions if it takes forever for it to downshift, my slipping unit with 120k miles on it snapped off the 3-2 or the 2-1 in like 2/10th of a second. Try this; when you're lining up, give the gas a little jab to like 50% or so and it will downshift to the proper gear without really moving you much, then honk off and go. The PCM will hold a low gear for a certain amount of time after you do this because it senses power demand. This > than timing the honks.
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