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riverjet
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459 Posts
Discussion Starter #1
Four years ago I had my trans rebuilt with all the upgrades (extra clutches,valve body mods,billet converter,ect.) Trans had alight 3-4(slip or flare).Shop said I needed a chip to run the billet tripledisk converter so I got a DP tuner.Bingo flare gone for good.Converter would break the tires loose on lockup, and 3-4 shift was strong.Now four years later and14k miles on the trans,my tuner updated the tunes and the flare is back again.Tuner said to go in the trans and drill the shift plate 3-4 hole bigger.Well I find out the only thing my builder did was put in a .427 mod valve,so I install a Tugger kit and drill the holes to(.125 1-2/.109 2-3/.109 3-4)and install a Sonnex 3-4 shift valve. Trans shifts super nice now and will break the tires loose on the 1-2 shift. 2-3 is nice(I am going to drill the .125)3-4 is real nice,but alittle light under light throttle. Every 1 in 100 shifts will flare about 50 rpm.I am waiting on my .500 mod valve in hopes of a cure.It seems like the more line pressure I run,it seems to help it.The flare occurs under very light throttle only.Why?What should I look for?I hope the .500 valve wil not be too harsh during normal driving.
 

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riverjet
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459 Posts
Discussion Starter #2
Where is Speeddemmon?
 

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Failure to Communicate
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1,133 Posts
the flare is there under light throttle cause the demanded line pressure is the lowest so that shift/lockup is a little slower.

it's a fine line for matching up the speed on the lock and the shift to not have a flare, generally if they crank up the pressure enough in the tune it will compensate.
 

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riverjet
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459 Posts
Discussion Starter #4
the flare is there under light throttle cause the demanded line pressure is the lowest so that shift/lockup is a little slower.

it's a fine line for matching up the speed on the lock and the shift to not have a flare, generally if they crank up the pressure enough in the tune it will compensate.
Most of the time my lockup is well before the shift(36mph),and the 3-4 is at 45.My updated tuning locks up the converter much softer. Is the converter unlocking slightly during the shift (pwm) ? I can not detect it with my lockup light.
 

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Demon Dually
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5,140 Posts
Here I is. The .500 will increase the line pressure and possibly eliminate the flare up from 3-4 but the problem is that I think you have an internal seal leak of some sort that you have had the whole time. By putting the tuned chip in you most likely only increased line pressure which stopped the flare temporarily until you got the new tuning which didn't have the same tune to up the line pressure again. Once the converter locks it should not unlock until you either hit the brakes or get down below 35 mph again. If the converter is unlocking before that then you may have a faulty TCC solenoid or weak spring. My honest opinion is that for you to run what you have in your sig you should consult John Woods or Brian at BTS for a properly set up valve body. You can't beat the price or reliability. They may even be able to cure your flare issue without tuning.
 

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riverjet
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459 Posts
Discussion Starter #6
Thanks guys!Yes,I contacted BTS and he said transgo with some otheir valves is what he uses and stay with my set up but drill the3-4 hole bigger.He said he would gladly sell me his valve body but didn't think it was needed.My converter is staying locked up once it locks and will not unlock till 25 mph.John woods does not use a plate and only a .327 valve.How about my solinoide pack?I have heard about not having the proper flow with aftermarket packs on the3-4 shift.
 

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Demon Dually
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5,140 Posts
The solenoids are either on or off except for the EPC solenoid which is variable and it controls line pressure. If it was acting up though your OD light would be flashing. Sounds like Brian has you moving in the right direction. I wasn't referring to the shift kit giving you and issue. I was referring to the torque converter clutch valve in the pump. Most builders change out the valve and spring assembly in the pump for better clutch lockup but it sounds like yours is already done if you are chirping the tires upon lockup.
 

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riverjet
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459 Posts
Discussion Starter #8
The solenoids are either on or off except for the EPC solenoid which is variable and it controls line pressure. If it was acting up though your OD light would be flashing. Sounds like Brian has you moving in the right direction. I wasn't referring to the shift kit giving you and issue. I was referring to the torque converter clutch valve in the pump. Most builders change out the valve and spring assembly in the pump for better clutch lockup but it sounds like yours is already done if you are chirping the tires upon lockup.
You might be on to something. With my updated tuning,converter lock up is much softer....it will no longer light up on lockup.The new tuning is really watered down when compairing the shifts to the old tuning....car like might be the word. My tuner said the old tunes were" transmission killers".
 
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