What would help? 2-3 shift
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From: Carol Stream Il.
What would help? 2-3 shift I only need a few more runs out of the current stock trans. It shifts fine NA but had a hard time going into 3rd while spraying a 125 shot. To help that I lowered the nitrous off point to 6k instead of trying to spray though the 6300 shift point. It shifted much better, but still hesitated a bit. I'm going to lower the nitrous off point by another 100 rpm, but is there anything else that could be done to help? Change the filter and fluid? Would a better servo such as a Sonnax billet help. I know nothing about transmissions and any help would be appreciated. Thanks
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The Sonnax 2nd gear band apply servo will help as it is the 3rd gear accumulator, forcing more oil to the clutches. The "modified" TransGo Performance Shift kit will help also. Make sure you use the OD position and not the D position when drag racing. This will give more oil to the 3-4 clutches on the 2-3 WOT shift. I would not do any more WOT 2-3 shifts with nitrous until you fix this, as this can finish off the 3-4 clutches in a very short time.
You also may want to allow a little more room in tuning between the commanded shift time and actual shift time. For example if you want to shift at 6300 set the comanded shift point at 5800 to 6000, Which willl work depends on the actual condition of your 3-4 clutch set.
__________________
You also may want to allow a little more room in tuning between the commanded shift time and actual shift time. For example if you want to shift at 6300 set the comanded shift point at 5800 to 6000, Which willl work depends on the actual condition of your 3-4 clutch set.
Yeah but yah never know which way it will go when tuning... Maybe to get a 6300 RPM shift you have to command 6500... or it could be that you have to command 6100, or even the 6300 it actually shifts at (though it's rare). I have seen a few built 4l60e's that just shift when they want to, regardless of WHAT you do with the numbers. I know, with shift-noids that doesn't make sense, but I have fought with 3 of them now. First one: (https://ls1tech.com/forums/showthrea...commanded+past)
That shift point may as well be some slider that you just move up or down with no numbers on it until it shifts when you want it to rather than a commanded RPM. Leave plenty of room for your rev limiter above the shift too. That's a table that WILL stick to RPM
If you have a copy of the tune I can take a look at it for ya.
Last edited by Frost; Jan 20, 2008 at 11:20 AM.
To some exstent this is true, But not because the solenoids and trans do not react, They must tun on or off when comanded, However in tuning there are so many variables other than RPM and MPH that cam affect the shift command, The MAF tell the PCM what the load is. The TPS tells the trans throttle position and there are other variables to. So yes at times it can be quite fustrating. Ran into one guy recently who was have the problem of shifting way early only at WOT after a cam heads install, He had to change setting in the PCM for TPS % to correct this. Now bear in mind I am not a tuner but do collect alot of information about it through working with people sloving transmission issues.
Now if you want to verify a trans will shift if commanded . Make or get a shift box like this one from a write up in one of our post, Or find a shop with a device called a schafer shifter. This will allow you to know TRANS or TUNING issue period.
Here at PerformaBuilt we are allways looking for ways we can help our customers, We have and even provide test equipment when needed, The Picture below is of one such device. It has over the past year saved both us and the customer $1000 of dollars in unessesary repairs and returns.
We actually have two of these. I built them they are not the prettiest but very functional. As you can see there are a series of switches. The first two to the left of the picture turn the Shift solenoids A and B or (1-2 and 2-3) shift soleniods off and on.
This box is plugged directly into the transmission.Using these two swicthes you can create any gear and verify that the transmission is capable of shifting reguarless of the PCM comand.
The next switch over is lockup enable. This switch will turn on the converter clutch. This is vey helpfull in determining if a lockup issue is trans/ converter related or tuning/pcm related. The small red push button lower left is for the PCS its a simple test max or min line presure and is used to verify normal shifts in conditions similar to Light throttle or WOT. The small black button is for the 3-2 solenoid and while you really cant feel any change with it its was included to verify function by ear listening to it click.
This box has a long cable and plugs into your lighter socket and the directly to the trans round plug on top. This way you can keep it in the car with you and verify function in all conditions. And it still does even more if either of the 1-2,2-3 or lockup solenoid or circuits is open it will illuminate both the red and green LEDs at the same time. This would instantly tell you there was and open connection to one of these solenoids. Alternatly if theres a short, the orange LED at the lower right will go off as power will be disabled to the box again telling you there was and electrical issue with a shorted internl transmission wire or solenoid.
In normal operation the red LED is on when the solenoid is off and the green LED is on when the solenoid is on. We use this box when a customer seems to have and issue with shifting of some sort that cannot be explained or with lockup.
We send it to the customer so they will not have to spend $ and lots of time chasing there tails over these type issues. Which I know all of you see these Type problems pop up regularly with any vendors trans or converter regularly (no lockup-Wont upshift-Wont downshift etc).
With this our customer can know without guess work where to look for a problem. If the box allows all to work normally then they know to look at the tuning if the box cannot cause normal operation. Then We know the correct direction to head to help get the issue solved. Most of the time the box when it goes out ends up only verifying the trans is in working order.
Now some might say you could duplicate this with a tuner or tuning software and even some scanners and to some extent that is true. However we have see cases for instance where a tuner was used to comand lockup and no lockup occurred and yet with this device it worked normally.
When this happens even though tuning is not part of what we offer we have yet another box I do not have a picture of it as there is only one and it is on loan to one of our dealers presently. The other box has leads on it I call puncture leads. There function is to be directly connected to the cars harness wires one for each solenoid. this may be done under the car or at the PCM. We send diagrams for both but its generally simpler to hook at at harness under car . It has and LED for each solenoid in the trans . The LEDs will light up when the PCM turns on any solenoid. This has in a few cases though its not common proved that just because the tuning software or a scanner says something was comanded or turned on (lockup) (shift solenids) That does not mean that the PCM actually did it.
Anyway I thought you guys might find this interesting its a handy tool That I built. Though you can buy similar tool called breakout boxes or schafter shifters in the after market they cost 1000s dollars and we couldnt risk just sending one of those out so this was a low cost solution to further help our customers in anyway we can.
We are allways committed to helping our customers solve any issue they may have reguardless of the cause or reason.
This is one area where that year of electronics engineering in school comes in handy. Just wish I had done better in english and grammer
We do this because we realize most of our customers are working on there own cars and may not have or have access to specialty test equipment.
Now if you want to verify a trans will shift if commanded . Make or get a shift box like this one from a write up in one of our post, Or find a shop with a device called a schafer shifter. This will allow you to know TRANS or TUNING issue period.
Here at PerformaBuilt we are allways looking for ways we can help our customers, We have and even provide test equipment when needed, The Picture below is of one such device. It has over the past year saved both us and the customer $1000 of dollars in unessesary repairs and returns.
We actually have two of these. I built them they are not the prettiest but very functional. As you can see there are a series of switches. The first two to the left of the picture turn the Shift solenoids A and B or (1-2 and 2-3) shift soleniods off and on.
This box is plugged directly into the transmission.Using these two swicthes you can create any gear and verify that the transmission is capable of shifting reguarless of the PCM comand.
The next switch over is lockup enable. This switch will turn on the converter clutch. This is vey helpfull in determining if a lockup issue is trans/ converter related or tuning/pcm related. The small red push button lower left is for the PCS its a simple test max or min line presure and is used to verify normal shifts in conditions similar to Light throttle or WOT. The small black button is for the 3-2 solenoid and while you really cant feel any change with it its was included to verify function by ear listening to it click.
This box has a long cable and plugs into your lighter socket and the directly to the trans round plug on top. This way you can keep it in the car with you and verify function in all conditions. And it still does even more if either of the 1-2,2-3 or lockup solenoid or circuits is open it will illuminate both the red and green LEDs at the same time. This would instantly tell you there was and open connection to one of these solenoids. Alternatly if theres a short, the orange LED at the lower right will go off as power will be disabled to the box again telling you there was and electrical issue with a shorted internl transmission wire or solenoid.
In normal operation the red LED is on when the solenoid is off and the green LED is on when the solenoid is on. We use this box when a customer seems to have and issue with shifting of some sort that cannot be explained or with lockup.
We send it to the customer so they will not have to spend $ and lots of time chasing there tails over these type issues. Which I know all of you see these Type problems pop up regularly with any vendors trans or converter regularly (no lockup-Wont upshift-Wont downshift etc).
With this our customer can know without guess work where to look for a problem. If the box allows all to work normally then they know to look at the tuning if the box cannot cause normal operation. Then We know the correct direction to head to help get the issue solved. Most of the time the box when it goes out ends up only verifying the trans is in working order.
Now some might say you could duplicate this with a tuner or tuning software and even some scanners and to some extent that is true. However we have see cases for instance where a tuner was used to comand lockup and no lockup occurred and yet with this device it worked normally.
When this happens even though tuning is not part of what we offer we have yet another box I do not have a picture of it as there is only one and it is on loan to one of our dealers presently. The other box has leads on it I call puncture leads. There function is to be directly connected to the cars harness wires one for each solenoid. this may be done under the car or at the PCM. We send diagrams for both but its generally simpler to hook at at harness under car . It has and LED for each solenoid in the trans . The LEDs will light up when the PCM turns on any solenoid. This has in a few cases though its not common proved that just because the tuning software or a scanner says something was comanded or turned on (lockup) (shift solenids) That does not mean that the PCM actually did it.
Anyway I thought you guys might find this interesting its a handy tool That I built. Though you can buy similar tool called breakout boxes or schafter shifters in the after market they cost 1000s dollars and we couldnt risk just sending one of those out so this was a low cost solution to further help our customers in anyway we can.
We are allways committed to helping our customers solve any issue they may have reguardless of the cause or reason.
This is one area where that year of electronics engineering in school comes in handy. Just wish I had done better in english and grammer
We do this because we realize most of our customers are working on there own cars and may not have or have access to specialty test equipment.
__________________
I have an even more crude version... I used a GM weatherpack/metripack connector and long leads and did the switching with my hands; though that was with a different project.
There really aren't that many trans variables/tables, and once you have it in your mind how they all work together, it's not ususally much work to get it to do what you want. I went through an exhaustive list of items and the one that I posted about above just did what it wanted to. 5800-5900 1 to 2, 6100 2 to 3. Could command 7K or 2K, TPS read 100%, MAF perfectly calibrated and working, MPH table moved way up, way down, and even zero'd out to force full RPM-based WOT shifting. It's not just me, I have reports (have that link I posted also posted at HPTuner's forum) that many other tuners have run across a trans or two that just would not do what ya wanted.
That is a nifty device, makes me want to break out that extended pigtail I have and do the same.
There really aren't that many trans variables/tables, and once you have it in your mind how they all work together, it's not ususally much work to get it to do what you want. I went through an exhaustive list of items and the one that I posted about above just did what it wanted to. 5800-5900 1 to 2, 6100 2 to 3. Could command 7K or 2K, TPS read 100%, MAF perfectly calibrated and working, MPH table moved way up, way down, and even zero'd out to force full RPM-based WOT shifting. It's not just me, I have reports (have that link I posted also posted at HPTuner's forum) that many other tuners have run across a trans or two that just would not do what ya wanted.
That is a nifty device, makes me want to break out that extended pigtail I have and do the same.
Well you are correct there are certain issue that can occur with the trans that can cause it to not respond , The obvious would be a slipping clutch of course but I ran into and issue last year with a unit and learned that some builder for a reason I do not understand will enlarge the feed holes to the shift solenoids and this can cause a condition known as solenoid flooding and oddly it can even be intermitant , What happens is the holes are solarge they cannot vent the fluild and the shift valve will fail to move resulting in a no upshift condition, Generally it will only effect the 2-3 shift but I imagine if they were made really to large they could affect the 1-2 also.
Another thing that can affect this I have seen is excessive line presure the levels you would get with a built trans which allready has increased line in the build coupled with raisng the line way up in tuning, Thats why we tell all our customers to leave the line presure setting alone in tuning. I know alotta guys after installing a big stall will try to get back that solid shift feel they had before by doing this not realizing the trans is still shifting as firmly as it ever did its just the converter cushions the affect.
And thanks on the box its proven several times now to be and invaluable tool and saved us and customers 1000s of dollars in unesesary repairs. We have even had non customers and persons who got there trans elsewhere to call and ask to borrow or rent it. We presently have two but have considered building several so we can do just that. Aditionally though I dont have a picture we have another box that taps into the wires feeding all the solenoids by peircing then like a needle would and iy can be used to watch LEDs to see just what the solenoids are really being commanded to do by the PCM its a handy tool also.
Another thing that can affect this I have seen is excessive line presure the levels you would get with a built trans which allready has increased line in the build coupled with raisng the line way up in tuning, Thats why we tell all our customers to leave the line presure setting alone in tuning. I know alotta guys after installing a big stall will try to get back that solid shift feel they had before by doing this not realizing the trans is still shifting as firmly as it ever did its just the converter cushions the affect.
And thanks on the box its proven several times now to be and invaluable tool and saved us and customers 1000s of dollars in unesesary repairs. We have even had non customers and persons who got there trans elsewhere to call and ask to borrow or rent it. We presently have two but have considered building several so we can do just that. Aditionally though I dont have a picture we have another box that taps into the wires feeding all the solenoids by peircing then like a needle would and iy can be used to watch LEDs to see just what the solenoids are really being commanded to do by the PCM its a handy tool also.
__________________
Last edited by performabuilt; Jan 20, 2008 at 12:12 PM.
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FormerVendor
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
SInce day one we have never had an issue with one of our units making a 1-2 shift at any power level, any power adder. Not one unit had an issue. My point there is not to blow our horn, rather the point is these are easy units to get a very consistant 1-2 shift out of.
The 2-3 shift is a completely different animal. Like Dana mentione... A Sonnax servo is a good answer, leaving the shifter in OD is a good idea and obviously a very well built 3/4 clutch pack is paramount. There is no room for error in that stack.
To the OP.... do not spray in 3rd unless you are prespared to replace the unit. If it has slipped more than once it is going to continue doing it. Point is all the tools in the world aren't going to be a substitute for a Professionally Built Racing transmission. And that is what you need. Adjusting and tweaking the power adder and shift tables is only prolonging the inevitable. Your transmission is hurt and it is only a matter of time before it stops shifting into 3rd and 4th.
To Formula98ramair.... your post would get much more attention if it had it's own Thread....
I am in North Richland Hills. Clode enought that you could call me and then bring it by for me to look at. Who built it?
Specifically, what trouble are you referring to?
g
The 2-3 shift is a completely different animal. Like Dana mentione... A Sonnax servo is a good answer, leaving the shifter in OD is a good idea and obviously a very well built 3/4 clutch pack is paramount. There is no room for error in that stack.
To the OP.... do not spray in 3rd unless you are prespared to replace the unit. If it has slipped more than once it is going to continue doing it. Point is all the tools in the world aren't going to be a substitute for a Professionally Built Racing transmission. And that is what you need. Adjusting and tweaking the power adder and shift tables is only prolonging the inevitable. Your transmission is hurt and it is only a matter of time before it stops shifting into 3rd and 4th.
To Formula98ramair.... your post would get much more attention if it had it's own Thread....
I am in North Richland Hills. Clode enought that you could call me and then bring it by for me to look at. Who built it?
Specifically, what trouble are you referring to?
g
Thread Starter
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From: Carol Stream Il.
The Sonnax 2nd gear band apply servo will help as it is the 3rd gear accumulator, forcing more oil to the clutches. The "modified" TransGo Performance Shift kit will help also. Make sure you use the OD position and not the D position when drag racing. This will give more oil to the 3-4 clutches on the 2-3 WOT shift. I would not do any more WOT 2-3 shifts with nitrous until you fix this, as this can finish off the 3-4 clutches in a very short time.
I'm sure you guys know how it is. Gotta do what you gotta do sometimes. I'm not spraying till 4k, so I'll lower that to 3400 to help flash the converter higher. That alone should pick up my 60ft. plus help me cross the line at a better rpm. That might get me that last tenth or so that I need.PBA, I do leave it in drive. So should I leave it in drive to launch and then shift to 4th for the 2-3 shift to be better? Or just leave it in 4th for the whole run? I do have some kind of shift kit, but no idea what was done. I gave the shop that install my old Vig. 2800 a transgo but thay told me they have their own way of doing things, and have no idea what parts they used if any, from the transgo.
So I guess I'll try the Sonnax servo, new filter, lower the nitrous off point another 100 rpm, and put the trans in 4th once I leave the line.
I would like to thank the rest of you too, for your help and ideas. Rick
FormerVendor
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
After looking back through this and reviewing the p.m.'s.
I must say if i was looking to finisha race or make some money.... limit the abuse around the 2/3 upshift and hit it hard!
Sounds to me like you are planning to replace it soon enough anyways.
If you need a Servo I could get one out to you tomorrow. Give me a call if I can be of any help.
g
I must say if i was looking to finisha race or make some money.... limit the abuse around the 2/3 upshift and hit it hard!
Sounds to me like you are planning to replace it soon enough anyways.
If you need a Servo I could get one out to you tomorrow. Give me a call if I can be of any help.
g
Back from the dead.
I was told to leave my stock A4 in D for racing. Is OD better?
Which is harder on these trannies, leaving at 3800rpm on slicks with a vig verter and stock power or the 2-3 shift?
Which position while drag racing (D or OD) will be the best to prolong a tranny's life? I guess while I'm asking, is it ok to slide it into OD (assuming I still run in D after this) after the traps to bring down the rpm?
I was told to leave my stock A4 in D for racing. Is OD better?
Which is harder on these trannies, leaving at 3800rpm on slicks with a vig verter and stock power or the 2-3 shift?
Which position while drag racing (D or OD) will be the best to prolong a tranny's life? I guess while I'm asking, is it ok to slide it into OD (assuming I still run in D after this) after the traps to bring down the rpm?
Personally I think its best to leave the line in D the overun clutch will be on and help support the input sprag. However it is also true its better to be in OD during the 2-3 shift,
So what I have done and tell people launch in D then as soon as the 1-2 shift is complete move the shifter to OD .IMO this works well .
So what I have done and tell people launch in D then as soon as the 1-2 shift is complete move the shifter to OD .IMO this works well .
__________________
bringing this back from the dead but been searching and well i have the opp. effect from above and so does my friend. Me and a guy down here have issues on the 2-3 shift when spraying with the car in od. It hangs up on the rev limiter a few times then shifts. In drive it doesnt happen at all, shifts perfect
I,ve daily driven and made track passes with a pressure guage sticking out between the hood and wipers to monitor the trans pressure. (looked odd but it worked great, I do this every time I refresh the tranny. I monitor for at least a few weeks) I also get a good idea on what effect the tranny temp has on the pressure. I wont pull to the burnout box till the temp is under 150 deg. (if I can avoid it) WOT into 3rd with a hot tranny is NOT good. The 2-3 shift will benifit from leaving it in OD. The pressure drop is much less and the pressure recovery is much quicker. Just backing up whats been already been said.
Mec
Mec
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From: Carol Stream Il.
The trans is still alive, since Iv'e only been to the track twice this year and only 4 nitrous runs. It does seem like it shifts better from 2nd to 3rd when it's in OD. I leave in drive and shift to OD after the 1-2 shift. No high 10s yet but hopefully we'll have the gremlin that popped up figured out in time for the fall air.
