4L60E Pinless 3-4 accumulator
The reason is that GM copied much of the 200-4r ideas into the 700
Another reason is because grandma in her buick might have noticed 4th gear...ever felt a stock as they come 700? Damn thing is almost a CVT how it slides between gears.
the 3-2 downshift timing valves were great on paper and bad in practice on the 2004r and the 700r4
the 1-2 accum I 100% agree KFX...needs to be functional and needs to protect the internals.
But the 3-4 accum I disagree...not needed for protection there. You'll be hard pressed to make 4th too firm...especially too firm to hurt something.
And IDK anyone that needs 4th gear WOT shifts...60e I built for a foxbody with 4.30's and a 26" tire might make a 3-4 WOT in the 1/4...but that would be at 120mph+
anybody with 3.73's or less likely won't need a 3-4 shift at WOT
Another reason is because grandma in her buick might have noticed 4th gear...ever felt a stock as they come 700? Damn thing is almost a CVT how it slides between gears.
the 3-2 downshift timing valves were great on paper and bad in practice on the 2004r and the 700r4
the 1-2 accum I 100% agree KFX...needs to be functional and needs to protect the internals.
But the 3-4 accum I disagree...not needed for protection there. You'll be hard pressed to make 4th too firm...especially too firm to hurt something.
And IDK anyone that needs 4th gear WOT shifts...60e I built for a foxbody with 4.30's and a 26" tire might make a 3-4 WOT in the 1/4...but that would be at 120mph+
anybody with 3.73's or less likely won't need a 3-4 shift at WOT
If it works...let it keep working!!
p.s. @Kfxguy head back over to your thread and toss everybody an update. would be cool to keep that thread alive and towards the top so more people can see it
p.s. @Kfxguy head back over to your thread and toss everybody an update. would be cool to keep that thread alive and towards the top so more people can see it
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3-4 accumulator block Don't cop an attitude...your question has been answered. Look at post #7. It says how it would affect the 3-4 shift.
look at how the oil flows...it flows in from the top of the bore. pushing the piston towards the separator plate...sooo...if you flip that setup over and install the spring into the case first...that will stroke the accumulator faster...meaning the shift will be softer.
You DO NOT want a softer 3-4 shift. Even with accumulator blocked the shift is usually never ever too firm.
Eliminating the accumulator altogether makes a shift as firm as it can get (excluding feed hole size, clutch count/clearance, etc)
Jays...when you block the accum, you omit the piston to ensure the rear geartrain still gets lube. You can see the orifice in the end of the bore...little cup plug with a hole in it. That orifice normally sees 4th gear oil and it sprays into the case.
When you block 4th accum...that orifice no longer sees any oil UNLESS you leave the piston out. Then the orifice sees accumulator oil in all gear ranges. Better lube.
look at how the oil flows...it flows in from the top of the bore. pushing the piston towards the separator plate...sooo...if you flip that setup over and install the spring into the case first...that will stroke the accumulator faster...meaning the shift will be softer.
You DO NOT want a softer 3-4 shift. Even with accumulator blocked the shift is usually never ever too firm.
Eliminating the accumulator altogether makes a shift as firm as it can get (excluding feed hole size, clutch count/clearance, etc)
Jays...when you block the accum, you omit the piston to ensure the rear geartrain still gets lube. You can see the orifice in the end of the bore...little cup plug with a hole in it. That orifice normally sees 4th gear oil and it sprays into the case.
When you block 4th accum...that orifice no longer sees any oil UNLESS you leave the piston out. Then the orifice sees accumulator oil in all gear ranges. Better lube.
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From: Iowa
In practice? No
In my mind...Yea. I always block from the outside of the bore. That way the high pressure 4th gear oil will only try to drive the ball deeper instead of spitting it out.
Really, the best thing to do would be to tap the hole for a 5/16 set screw and use a dab of loctite. that way it will never come out from pressure...but you can un-do it later on down the road if desired.
Driving the ball into the case is tough if not nearly impossible to undo
In my mind...Yea. I always block from the outside of the bore. That way the high pressure 4th gear oil will only try to drive the ball deeper instead of spitting it out.
Really, the best thing to do would be to tap the hole for a 5/16 set screw and use a dab of loctite. that way it will never come out from pressure...but you can un-do it later on down the road if desired.
Driving the ball into the case is tough if not nearly impossible to undo
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From: Nitro Alley
Yup as usual, Maroon Monster just gave you perfect advice.
I personally do not ever use a check-ball or cup-plug to block passages.
I prefer using a set-screw or threaded plug (but this comes from experience with cup-plugs blowing-out inside engines).
I personally do not ever use a check-ball or cup-plug to block passages.
I prefer using a set-screw or threaded plug (but this comes from experience with cup-plugs blowing-out inside engines).
Have any of you blocked the 3/4 accumulator and then stacked the pistons in the bore?
The tip of taping the hole with and using a set screw is a GREAT tip. I always cringe when I hear or see someone using a check ball. Which works, but you cant usually go back.
The tip of taping the hole with and using a set screw is a GREAT tip. I always cringe when I hear or see someone using a check ball. Which works, but you cant usually go back.
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From: Nitro Alley
But doing so, will block off additional lube oil to the Low-Reverse clutch... and it is better to avoid doing so.
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From: Nitro Alley
Unless using a very high stall speed torque-converter... this is usually a bad idea; and can be harmful to the transmission.
There are several ways to easily have a firm or super-firm shift into 2nd gear without blocking the 2nd accumulator.
There are several ways to easily have a firm or super-firm shift into 2nd gear without blocking the 2nd accumulator.
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From: Iowa
Do not stack pistons in the 3/4
And for the love of god do not block the 1-2
The 1-2 shift is VERY easy to make firm (even TOO firm) with a functional accumulator.
This isn't 1987 where uncle jimmy's cutlass can jump a coke can at a stoplight and give you a 1-2 scratch every time. Even at 5mph
Hard shifts=/=good shifts
And for the love of god do not block the 1-2
The 1-2 shift is VERY easy to make firm (even TOO firm) with a functional accumulator.
This isn't 1987 where uncle jimmy's cutlass can jump a coke can at a stoplight and give you a 1-2 scratch every time. Even at 5mph
Hard shifts=/=good shifts
Do not stack pistons in the 3/4
And for the love of god do not block the 1-2
The 1-2 shift is VERY easy to make firm (even TOO firm) with a functional accumulator.
This isn't 1987 where uncle jimmy's cutlass can jump a coke can at a stoplight and give you a 1-2 scratch every time. Even at 5mph
Hard shifts=/=good shifts
And for the love of god do not block the 1-2
The 1-2 shift is VERY easy to make firm (even TOO firm) with a functional accumulator.
This isn't 1987 where uncle jimmy's cutlass can jump a coke can at a stoplight and give you a 1-2 scratch every time. Even at 5mph
Hard shifts=/=good shifts
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From: Iowa
blocking the 3/4 accumulator with a setscrew will be more effective than stacking the pistons.
When you stack the pistons and block the hole...you kill lube to the rear planet.
If you look in the bottom of the bore of the 3/4 accum you will see a small copper cup plug with a .030 ish hole
That hole is spray lube for the rear geartrain
If you block the hole and stack pistons, no oil gets to that lube hole.
stock form with functional accumulator, you'll have lube to that hole only in 4th gear
Modified form (plug hole with setscrew and throw piston away) you'll have accumulator bias oil feeding that orifice at all times. So all gears get added lube to the rear geartrain
When you stack the pistons and block the hole...you kill lube to the rear planet.
If you look in the bottom of the bore of the 3/4 accum you will see a small copper cup plug with a .030 ish hole
That hole is spray lube for the rear geartrain
If you block the hole and stack pistons, no oil gets to that lube hole.
stock form with functional accumulator, you'll have lube to that hole only in 4th gear
Modified form (plug hole with setscrew and throw piston away) you'll have accumulator bias oil feeding that orifice at all times. So all gears get added lube to the rear geartrain
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From: Nitro Alley
-There is a lube oil orifice in the bottom of the bore for the 4th accumulator piston.
-This is lube oil for the Low-Reverse clutch.
-If you stack pistons here... you will lose the additional lube oil to the Low-Reverse clutch.
-Use a 5/16" tap and set-screw to block the 4th oil feed into the 4th accumulator bore.
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From: Texas
Is this the correct hole to block? Because to me, it seems like this would keep the cup-plug from getting lube.
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From: Nitro Alley
When the bore is left empty...
Fluid will enter the bore from the passage at the top of the bore (at 4:30 in your image) this fluid is 4th accumulator fluid/ orificed accumulator fluid (and will allow oil to pass through the orifice at the bottom of the bore).