4th accumlator piston
#2
Moderator
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You basically already asked this question last week in this thread:
https://ls1tech.com/forums/automatic...questions.html
PBA, a pro builder with 30 years experience gave you a very good and detailed answer of how to absolutely maximize the shift stiffness. Personally I wouldn't want to go that stiff, but you asked and PBA told you.
Blocking the feed hole to any accumulator is a good way to break the trans. Years ago kids with 175HP V6 would install shift kits with disabled accumulators (e.g. B&W) so that they could chirp the tires during shifts. If you try that with a 400+ HP engine you will quickly break the trans internals or the U-joints.
https://ls1tech.com/forums/automatic...questions.html
PBA, a pro builder with 30 years experience gave you a very good and detailed answer of how to absolutely maximize the shift stiffness. Personally I wouldn't want to go that stiff, but you asked and PBA told you.
Blocking the feed hole to any accumulator is a good way to break the trans. Years ago kids with 175HP V6 would install shift kits with disabled accumulators (e.g. B&W) so that they could chirp the tires during shifts. If you try that with a 400+ HP engine you will quickly break the trans internals or the U-joints.
#3
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actually i didn't ask this question in the orther post, in that post i was asking about the servo's not the 4th accumlator, are we limited on questions? i also just seen PBA responce to my questions, i guess i missed the reply. i will go with his suggestions thanks for all your help to both of you.
You basically already asked this question last week in this thread:
https://ls1tech.com/forums/automatic...questions.html
PBA, a pro builder with 30 years experience gave you a very good and detailed answer of how to absolutely maximize the shift stiffness. Personally I wouldn't want to go that stiff, but you asked and PBA told you.
Blocking the feed hole to any accumulator is a good way to break the trans. Years ago kids with 175HP V6 would install shift kits with disabled accumulators (e.g. B&W) so that they could chirp the tires during shifts. If you try that with a 400+ HP engine you will quickly break the trans internals or the U-joints.
https://ls1tech.com/forums/automatic...questions.html
PBA, a pro builder with 30 years experience gave you a very good and detailed answer of how to absolutely maximize the shift stiffness. Personally I wouldn't want to go that stiff, but you asked and PBA told you.
Blocking the feed hole to any accumulator is a good way to break the trans. Years ago kids with 175HP V6 would install shift kits with disabled accumulators (e.g. B&W) so that they could chirp the tires during shifts. If you try that with a 400+ HP engine you will quickly break the trans internals or the U-joints.
Last edited by 84c10; 10-30-2013 at 07:36 AM. Reason: add msg
#4
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actually i didn't ask this question in the orther post, in that post i was asking about the servo's not the 4th accumlator, are we limited on questions? i also just seen PBA responce to my questions, i guess i missed the reply. i will go with his suggestions thanks for all your help to both of you.
![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
But as you noticed (a bit late), PBA gave a detailed answer, including drilling the 4th feed hole in the separator plate.
You can/should subscribe to the threads with your posts (although I thought that was the default). Optionally you can receive an immediate, daily or weekly emails notifying you are additions to your subscribed threads.
#5
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Hey what do you like your 3-4 clutch pak set up at? Raybestos gpz frictions.
You are not limited on questions. ![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
But as you noticed (a bit late), PBA gave a detailed answer, including drilling the 4th feed hole in the separator plate.
You can/should subscribe to the threads with your posts (although I thought that was the default). Optionally you can receive an immediate, daily or weekly emails notifying you are additions to your subscribed threads.
![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
But as you noticed (a bit late), PBA gave a detailed answer, including drilling the 4th feed hole in the separator plate.
You can/should subscribe to the threads with your posts (although I thought that was the default). Optionally you can receive an immediate, daily or weekly emails notifying you are additions to your subscribed threads.
#6
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https://ls1tech.com/forums/automatic...some-info.html
Note that to build a 8 friction clutch, you should purchase 8x .067 frictions and 2x .080 frictions of the same type.
(e.g. get 8x GPZ105 and 2x GPZ100)
Then if your clearance with the thin frictions is more than desired, you use one or two thicker frictions to reduce it to the desired amount.
A brand new .215 or .223 apply plate is highly recommended to reduce the chance of coning.
Some builders prefer thicker frictions and thinner steels and then use one or two thicker steels to reach the desired clearance.
Be sure the 3rd accumulator check ball in the case by the servo is not leaking or brand new. Be sure to air test the assembled input drum, first by itself and then installed into the pump. Knowing how much leakage to expect (and where) during these tests takes some experience.
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#8
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And next question, I installed a transducer today and see that I have very poor line psi. Less than 100 at wot and 20-30 at idle. I can adjust psi with my controller but of course I have an issue somewhere. What are some things that can cause this? I took the pump apart and the vanes looked good. Thanks
My suggestions that a bunch of
members have followed are here:
https://ls1tech.com/forums/automatic...some-info.html
Note that to build a 8 friction clutch, you should purchase 8x .067 frictions and 2x .080 frictions of the same type.
(e.g. get 8x GPZ105 and 2x GPZ100)
Then if your clearance with the thin frictions is more than desired, you use one or two thicker frictions to reduce it to the desired amount.
A brand new .215 or .223 apply plate is highly recommended to reduce the chance of coning.
Some builders prefer thicker frictions and thinner steels and then use one or two thicker steels to reach the desired clearance.
Be sure the 3rd accumulator check ball in the case by the servo is not leaking or brand new. Be sure to air test the assembled input drum, first by itself and then installed into the pump. Knowing how much leakage to expect (and where) during these tests takes some experience.
members have followed are here:
https://ls1tech.com/forums/automatic...some-info.html
Note that to build a 8 friction clutch, you should purchase 8x .067 frictions and 2x .080 frictions of the same type.
(e.g. get 8x GPZ105 and 2x GPZ100)
Then if your clearance with the thin frictions is more than desired, you use one or two thicker frictions to reduce it to the desired amount.
A brand new .215 or .223 apply plate is highly recommended to reduce the chance of coning.
Some builders prefer thicker frictions and thinner steels and then use one or two thicker steels to reach the desired clearance.
Be sure the 3rd accumulator check ball in the case by the servo is not leaking or brand new. Be sure to air test the assembled input drum, first by itself and then installed into the pump. Knowing how much leakage to expect (and where) during these tests takes some experience.
#9
Moderator
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Glad you put a pressure gauge on the trans!
As you know the EPC (pressure control solenoid) controls the pressure according to how much current the PCM sends through it. With Zero current (also with trans connector unplugged) it sets the max pressure, which is typically 175psi with a stock boost valve and 225psi with a Sonnax or Transgo boost valve. With a high current (1.25 amps?) it sets the lowest pressure which is typically 50 psi with a stock boost valve.
So obviously you are way too low and your clutches are at risk of slipping.
I would make sure the boost valve and the pressure control valve are properly assembled.
What year is the trans?
Was a shift kit installed?
The Transgo boost valve includes a thick spacer which must be installed up to year 2005. Without it pressure will be low, but perhaps not this low.
When you assembled the pump, did you:
1. Remember to install the filter on the side of the pump?
Without it pressure will be very low.
2. Remember the o-ring under the oil seal? (Parts #201 and #202 in the GM diagrams.)
As you know the EPC (pressure control solenoid) controls the pressure according to how much current the PCM sends through it. With Zero current (also with trans connector unplugged) it sets the max pressure, which is typically 175psi with a stock boost valve and 225psi with a Sonnax or Transgo boost valve. With a high current (1.25 amps?) it sets the lowest pressure which is typically 50 psi with a stock boost valve.
So obviously you are way too low and your clutches are at risk of slipping.
I would make sure the boost valve and the pressure control valve are properly assembled.
What year is the trans?
Was a shift kit installed?
The Transgo boost valve includes a thick spacer which must be installed up to year 2005. Without it pressure will be low, but perhaps not this low.
When you assembled the pump, did you:
1. Remember to install the filter on the side of the pump?
Without it pressure will be very low.
2. Remember the o-ring under the oil seal? (Parts #201 and #202 in the GM diagrams.)
#10
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We'll tell me something else, I'm hoping I'm wrong here but I installed a 1600psi transducer in the cooler line. Is the cooler line the same psi or differ than the port on the drivers side? The reason I still believe I have issues is the way I'm having to run line pressure in all gears. I control with Holley EFI and it goes by duty cycle. So right now in all gears I have 0% duty cycle above 40% tps in all gears and not impressed with the 2-3 and 3-4 shift at all. I just but a stock 60e that has much better shifts with stock line pressure in all gears. Thanks for your help.
Glad you put a pressure gauge on the trans!
As you know the EPC (pressure control solenoid) controls the pressure according to how much current the PCM sends through it. With Zero current (also with trans connector unplugged) it sets the max pressure, which is typically 175psi with a stock boost valve and 225psi with a Sonnax or Transgo boost valve. With a high current (1.25 amps?) it sets the lowest pressure which is typically 50 psi with a stock boost valve.
So obviously you are way too low and your clutches are at risk of slipping.
I would make sure the boost valve and the pressure control valve are properly assembled.
What year is the trans?
Was a shift kit installed?
The Transgo boost valve includes a thick spacer which must be installed up to year 2005. Without it pressure will be low, but perhaps not this low.
When you assembled the pump, did you:
1. Remember to install the filter on the side of the pump?
Without it pressure will be very low.
2. Remember the o-ring under the oil seal? (Parts #201 and #202 in the GM diagrams.)
As you know the EPC (pressure control solenoid) controls the pressure according to how much current the PCM sends through it. With Zero current (also with trans connector unplugged) it sets the max pressure, which is typically 175psi with a stock boost valve and 225psi with a Sonnax or Transgo boost valve. With a high current (1.25 amps?) it sets the lowest pressure which is typically 50 psi with a stock boost valve.
So obviously you are way too low and your clutches are at risk of slipping.
I would make sure the boost valve and the pressure control valve are properly assembled.
What year is the trans?
Was a shift kit installed?
The Transgo boost valve includes a thick spacer which must be installed up to year 2005. Without it pressure will be low, but perhaps not this low.
When you assembled the pump, did you:
1. Remember to install the filter on the side of the pump?
Without it pressure will be very low.
2. Remember the o-ring under the oil seal? (Parts #201 and #202 in the GM diagrams.)
#13
Moderator
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OK, that confirms that the cooler lines are not at line pressure.
First, what stall converter do you have?
High stall converters soften shifts.
Give us details of what mods were made, what parts were used, what your 3/4 clearance is, and to what sizes the feed holes in the separator plate were drilled?
What parts/springs do you have in the 1-2 accumulator?
Also, did you eliminate torque management in the tune?
Also, I wonder about your expectations, especially if you have a high stall converter. I build my trans very firm, but use a modest tune. In easy driving the shifts are very fast but barely felt with my 3600 stall. In contrast the same setup with a 2400 stall chirped the tires on nearly every 1-2 shift (annoying) until I tuned for minimum pressure during easy shifts.
With WOT on the strip my shifts are very firm, right at 7000 rpm with no flare.
In summary, I suspect you have a high stall and/or have not fully disabled torque management in the tune.
First, what stall converter do you have?
High stall converters soften shifts.
Give us details of what mods were made, what parts were used, what your 3/4 clearance is, and to what sizes the feed holes in the separator plate were drilled?
What parts/springs do you have in the 1-2 accumulator?
Also, did you eliminate torque management in the tune?
Also, I wonder about your expectations, especially if you have a high stall converter. I build my trans very firm, but use a modest tune. In easy driving the shifts are very fast but barely felt with my 3600 stall. In contrast the same setup with a 2400 stall chirped the tires on nearly every 1-2 shift (annoying) until I tuned for minimum pressure during easy shifts.
With WOT on the strip my shifts are very firm, right at 7000 rpm with no flare.
In summary, I suspect you have a high stall and/or have not fully disabled torque management in the tune.
#14
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60e
Blue plate forward and over run. In gm spec
Raybestos gpz 105 3-4 at .045 wet
Trans go hd2 kit
All pinless pistons
1-2 pinless with purple and pink spring
4th with spring against case
Corvette 2nd servo with pink spring and cushion
Sonnax super 4th at .085
2500 converter on LS making 400hp or less
Beast sun shell
Sonnax servo release valve
New 3rd capsule
Holley dominator controlling engine and trans. No tq management and fully tunable
All forward gears running at 165psi or above at all times. Reverse around 200psi
Now to what I found, I remembered dropping the Vette servo so I pulled it out and found a hump around the sealing ring so I replaced it with a tci billet 2nd that I have. Measured out at .125. Shifts are great now except 2-3. I'm very picky and most might let this go. 1-2 is snappy and very firm, 4th is snappy and firm enough. 2-3 is firm but has a small delay before hitting. Will setting my band clearance closer help this? Or should I get another Vette servo?
Blue plate forward and over run. In gm spec
Raybestos gpz 105 3-4 at .045 wet
Trans go hd2 kit
All pinless pistons
1-2 pinless with purple and pink spring
4th with spring against case
Corvette 2nd servo with pink spring and cushion
Sonnax super 4th at .085
2500 converter on LS making 400hp or less
Beast sun shell
Sonnax servo release valve
New 3rd capsule
Holley dominator controlling engine and trans. No tq management and fully tunable
All forward gears running at 165psi or above at all times. Reverse around 200psi
Now to what I found, I remembered dropping the Vette servo so I pulled it out and found a hump around the sealing ring so I replaced it with a tci billet 2nd that I have. Measured out at .125. Shifts are great now except 2-3. I'm very picky and most might let this go. 1-2 is snappy and very firm, 4th is snappy and firm enough. 2-3 is firm but has a small delay before hitting. Will setting my band clearance closer help this? Or should I get another Vette servo?
#15
Moderator
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I don't have time right now for a detailed reply, but the Pinless 1-2 piston will not work properly withe the HD2 springs. Next time you have the pan off, put an aluminum piston back in. Pinless works great everywhere else, or in the 1-2 with the stock springs or a very special Sonnax springs.
Update - Sorry, I missed that you are using stock-style springs in the 1-2. That will work fine with the Pinless piston.
Update - Sorry, I missed that you are using stock-style springs in the 1-2. That will work fine with the Pinless piston.
Last edited by mrvedit; 11-02-2013 at 07:46 PM.
#17
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The 2-3 is always the softest shift in the 4L60E; first the large 3rd accumulator area has to fill, then the 3rd clutch has to activate, moving a significant number of parts. In contrast, the 1-2 and 3-4 shifts only need to fill a very small accumulator, then move the servo to bind the band.
The large 3rd accumulator area pretty much dooms any really quick 2-3 shift. As I understand it, installing the Vette or even bigger Billet servo will further slow down the 2-3 shift by a bit.
Since you have the Sonnax servo release valve installed, I assume you drilled the 3rd feed hole to .120/.125. And you drilled the valve to .120 too?
Therefore, it might be close to as good as it gets. The only improvement I see would be a tighter 3/4 clutch clearance. With brown frictions I generally aim for .035 to .040 wet, which comes out to .027 to .032 wet. Since you mention the GPZ105 frictions which are .067, next time install one GPZ100 which is .080 to reduce the clearance
Also did you install the Transgo spring kit? IMHO, installing the full set of springs is too stiff unless you shift at 8000+ rpm. I use half stock and half Transgo springs in each cage.
many things that have to happen:
1. Move servo back to disengage band.
2. Feed fluid
The large 3rd accumulator area pretty much dooms any really quick 2-3 shift. As I understand it, installing the Vette or even bigger Billet servo will further slow down the 2-3 shift by a bit.
Since you have the Sonnax servo release valve installed, I assume you drilled the 3rd feed hole to .120/.125. And you drilled the valve to .120 too?
Therefore, it might be close to as good as it gets. The only improvement I see would be a tighter 3/4 clutch clearance. With brown frictions I generally aim for .035 to .040 wet, which comes out to .027 to .032 wet. Since you mention the GPZ105 frictions which are .067, next time install one GPZ100 which is .080 to reduce the clearance
Also did you install the Transgo spring kit? IMHO, installing the full set of springs is too stiff unless you shift at 8000+ rpm. I use half stock and half Transgo springs in each cage.
many things that have to happen:
1. Move servo back to disengage band.
2. Feed fluid
#18
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3rd feed to .115 and the valve to .120 per instructions
I did not install the springs from the kit. I was advised not too
With the servo set up as I have it now the clearance is .125. If I use one of transgo spacers to get this tighter will that help? I'll try to explain the complaint better. 2-3 is the only problem, it's firm just seems there's a delay before engagement. Is this a flare? Not sure myself.
I did not install the springs from the kit. I was advised not too
With the servo set up as I have it now the clearance is .125. If I use one of transgo spacers to get this tighter will that help? I'll try to explain the complaint better. 2-3 is the only problem, it's firm just seems there's a delay before engagement. Is this a flare? Not sure myself.
#19
Moderator
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You have really built the trans well. Congrats!
Your question is beyond my experience/knowledge level.
One of the experienced builder will have to answer this.
Your question is beyond my experience/knowledge level.
One of the experienced builder will have to answer this.