Force lockup best speed
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Times? Quarter mile times? I assume you're referring to the TCC lock up. Does that forced lock up occur at WOT? What trap speeds are you running? If it isn't at least 105+ mph, raising it will have no effect. I have heard that some have experimented with locking up the converter, early, with a manual switch. In any case, I wouldn't expect locking the converter just before or in the traps will do any good. Failing experiments indicating the opposite, I would set the lock up for a speed, higher, than you ever expect to see during a run. When setting it, remember that the trap speed on the ET slip is an average speed over the last 66' of the 1/4, and lower than the exact speed exiting the final set of timers. Leave yourself a little cushion, based on that.
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Last edited by CFI-EFI; Apr 4, 2005 at 02:23 PM.
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Originally Posted by MR.KIDD
On my 85 in the constants table there is a force lockup ajustment parameter it is set at 109mph would it be best to lower this or up it for best times. 
Give it a try and I bet your ETs improve about .075-.1sec in the 1/4. WHen your looking for every ounce you might as well take advantage of it.
As for it being hard on stuff, well, I did it for 2 years with my vigilante, and never saw a problem.
Melting Slicks
Joined: Oct 2002
Posts: 3,193
Likes: 1
From: Cincinnati Oh
My understanding is with Jesse in that the earlier you lock up your converter (won't lock in 1st gear, so the tables are for 2-4th depending) will eliminate the "slip" in the TCC and be somewhat more efficient.
However, you are lowering the RPMs slightly with the lockup and that may hurt you depending on your gears, RPM and powerband. You may want to have the TCC lockup when you're just PAST peak power so the resulting drop in RPMs puts you back in the powerband until you then shift into third (and do the same if applicable).
just my opinion though.
However, you are lowering the RPMs slightly with the lockup and that may hurt you depending on your gears, RPM and powerband. You may want to have the TCC lockup when you're just PAST peak power so the resulting drop in RPMs puts you back in the powerband until you then shift into third (and do the same if applicable).
just my opinion though.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Forced lockup may help or hurt 1/4 mile times depending on shift points and power band. Remember that the A4 shifts from tail shaft input, so it will shift at lower RPM when the TCC is locked. But, since that parameter is speed dependent, it won't help till you hit the speed setpoint.
Before you change the EPROM table parameter I suggest you install a switch across ALDL pins A (upper Rt) & F (upper left). As soon as you hit the 1-2 shift close the switch; when you cross the stripes open the switch. Then you can compare back-to-back time slips to see if there is any benefit in your case.
Thread Starter
Racer
Joined: May 2004
Posts: 270
Likes: 0
From: NORFOLK VA.
Ok the car has 307 gears shifted at 5800 1/8 mile =94mph 1/4 mile =117mph and force lockup is at wot so I guess I will see what mph I am at when the second gear shift happens and set force lockup to that and see what happens.Thanks 
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Originally Posted by MR.KIDD
Ok the car has 307 gears shifted at 5800 1/8 mile =94mph 1/4 mile =117mph and force lockup is at wot so I guess I will see what mph I am at when the second gear shift happens and set force lockup to that and see what happens.Thanks
Kidd.
as said above, jumper the ALDL is the easiest and most consistant way, that is what I used to do in mine. it will feel horrible in the pits (like a standard in the wrong gears cause it will lug the motor way down when moving about.), but its will lock instantly on the 1-2 shift.
Be sure to break down your time slips to make a fair comparison. What you are doing with the lockup, is making the efficiency of the converter much higher, sooner, which should yield better ETs.
It will "feel" slower, and sound slower, but most likely will yield a better ET. My car "sounded" like you were going 100 more MPH with the converter unlocked, but always went slower that way. Locked is the ticket.
Thread Starter
Racer
Joined: May 2004
Posts: 270
Likes: 0
From: NORFOLK VA.
[QUOTE=ski_dwn_it]Kidd.
as said above, jumper the ALDL is the easiest and most consistant way, that is what I used to do in mine. it will feel horrible in the pits (like a standard in the wrong gears cause it will lug the motor way down when moving about.), but its will lock instantly on the 1-2 shift.
Ok if I jumper it will it be locked as long as it is jumped if so that would mean that it is locked in first gear also or will it only lock once it gets to the second shift and stay locked until it gets back to 1st gear.
as said above, jumper the ALDL is the easiest and most consistant way, that is what I used to do in mine. it will feel horrible in the pits (like a standard in the wrong gears cause it will lug the motor way down when moving about.), but its will lock instantly on the 1-2 shift.
Ok if I jumper it will it be locked as long as it is jumped if so that would mean that it is locked in first gear also or will it only lock once it gets to the second shift and stay locked until it gets back to 1st gear.
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