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5EAT owners with IPT valve body modification


spacejunkiehsv

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Did you speak with Tye at IPT? I've spoken with him about getting mine done. This was about a month ago. I was told it took 3/4 of a day for the job. If I got there at 8am it should be done by 2ish.

 

Called again about this today. Now they say the car has to be there for 48hours! So it went from a 6 hour job to needing the car for 2 full days.

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i suppose Tye was the one that had this down. :( so i wonder if there are other outfits that might be able to do this? however, i'd think it'd take them some time to figure it out too.... that sucks.
Wiggle wiggle wiggle wiggle wiggle yeah!!!
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Someone really needs to step up and crack the TCU in these things .. I'd be much more comfortable upping line pressure electronically as opposed to these seemingly mixed physical adjustment results.
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  • 1 month later...
Someone really needs to step up and crack the TCU in these things .. I'd be much more comfortable upping line pressure electronically as opposed to these seemingly mixed physical adjustment results.

 

I would have to agree with you...up to a point. For me I would simply like to increase line pressure electronically but for these folks that are putting some good power down it is always best to increase line pressure mechanically.

 

So, can someone please increase line pressure electronically for the rest of us? :)

 

Brian

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  • 3 weeks later...
would stage 2 require a vb upgrade? or should the 5eat be fine?

depends on how in depth your stage 2 set up is. i'm willing to bet, if i had the VB upgrade when i was just stg 2 (up, dp) i'd have more power getting to the ground and much quicker and cleaner shifts. but i don't know....

Wiggle wiggle wiggle wiggle wiggle yeah!!!
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depends on how in depth your stage 2 set up is. i'm willing to bet, if i had the VB upgrade when i was just stg 2 (up, dp) i'd have more power getting to the ground and much quicker and cleaner shifts. but i don't know....

 

 

The moment AKLGT's car rolled out of her garage after we did the STI Swap the car was begging for a stronger transmission. The valve upgrade was the first thing she did and it made all the difference.

 

If you are looking to go stage II or higher I would definitely include the valve upgrade... I was pretty skeptical that it would help but it really delivers the power to the road.

 

... and as she says she expects a lot out of her car.

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Every time you AK guys/gals talk about this, it makes me get more and more interested.

I've got a similar setup as AKLGT's, very happy with the power, and my trans is operating perfectly (no differently than stg 2, same speed of shift, no slips, etc), but if I've learned one thing on this board it's to take statements like "all the difference" from experienced ppl pretty seriously. And especially since my plan includes a bit more power for this car eventually, in one direction or another, this mod is definitely on my short list.

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The moment AKLGT's car rolled out of her garage after we did the STI Swap the car was begging for a stronger transmission. The valve upgrade was the first thing she did and it made all the difference.

 

If you are looking to go stage II or higher I would definitely include the valve upgrade... I was pretty skeptical that it would help but it really delivers the power to the road.

 

... and as she says she expects a lot out of her car.

:lol: :lol:

 

i'm a girl.... we expect a lot from just about everything! :lol:

 

and underpowered, anyone who's been in my car before and after will tell you the same: the VB upgrade hands down made a night and day difference. our local subie techs, AK Wagon, myself, even Jarrad from PDX all made note of how the car has more power and shifts quicker than most 5EATs allowing the power to get to the ground. until you have it done, there's no real way to describe how much different it is.

 

it's not cheap, but think of it this way: everyone who's done this mod has been pleased, happy and say it's worth it.

Wiggle wiggle wiggle wiggle wiggle yeah!!!
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While this was written by IPT concerning the Toyota AT, it gives a good overview of what their valve body upgrades accomplish:

 

Toyota Modified Valve Body

 

-By John Lombardo

 

© John Lombardo- All Rights Reserved

http://www.importperformancetrans.com

 

_____________________________________________________________________________________

_____________________________________________________________________________________

 

 

As many Toyota and Jeep owners know, the AW4 / Toyota 340, A340, and A341E series of transmissions are generally very well made and demonstrate excellent durability in unmodified applications. The framework is present for an extremely strong transmission that is to be used in a high performance or extreme duty application.

 

The problem is that the original calibration is engineered for driver comfort rather than ultimate component strength. The soft, sliding shifts that are part of the original design are not appropriate for increased horsepower applications, towing, off road use, racing, etc.

 

These calibration inadequacies quickly manifest themselves as extremely poor shift quality, and more often than not, severe damage to the gearbox is soon to follow. One of the most common symptoms of this is the engine stuttering or hitting the rev limiter during a full throttle upshift.

 

Without going into too much technical detail, the factory shortcomings can be addressed through modification and recalibration of the control valve assembly, a.k.a. the valve body.

 

The valve body is a component that is comprised of valves, solenoids, an orifice separator plate and an intricate series of passages- it is the most complex component in the most complex part of your vehicle- the automatic transmission.

 

The function of the valve body is to act as the "brain" of the automatic transmission- it directs hydraulic pressure to the appropriate clutches and bands at the right time to initiate upshifts, down shifts, selection of reverse, converter clutch application, etc. As well as controlling shift timing and shift quality, it is also responsible for directing hydraulic pressure to the cooler and the lubrication circuit.

 

As you can imagine, the transmission's operational characteristics can be drastically altered and also customized to the given application through modifications to this component.

 

Because there are no commercially available shift kits for these transmissions, we began working on valve body modifications that were appropriate for Supras, Jeeps with the AW4 transmission, Toyota Tundra, Tacoma and 4Runner, and also Lexus SUV’s and rear drive passenger cars- especially those that needed to handle the additional power that accompanies the installation of a supercharger, turbo or nitrous oxide injection.

 

At the risk of oversimplification, there are a few things that are done in concert to create much more favorable operation of the gearbox.

 

The first thing that needs to be done is to increase the hydraulic operating pressure of the transmission- this pressure is known as "line pressure". All hydraulic functions of the transmission are based on this pressure- what is especially of concern for these purposes is the clamping force which is applied to the clutches and bands to get them to hold against engine torque.

 

In simple terms, increased engine output is complemented by increased line pressure and increased "clamp" on the clutches- this can be likened to a performance clutch with a heavier pressure plate spring in a manual transmission equipped vehicle.

 

The idea is to raise this pressure only slightly at light throttle but increase it by 30-40% at full throttle- where it is really needed. The effects of this are shifts that are not overly uncomfortable at lower throttle openings, while at heavier throttle, firm shifts with much shorter clutch application time and increased clamping force can be achieved.

 

An additional benefit of this is increased flow through the transmission’s cooler and lube system.

 

Secondly, hydraulic pressure is normally routed through an orifice in a metal "separator plate" that resides between the two halves of the valve body before it gets to its intended destination. By altering these orifices, we can increase the volume of hydraulic oil that is used to apply the various clutches and bands.

 

The final part of modification is the alteration of the accumulator circuits. These are hydraulic circuits that are parallel to the components that are used for shifting. Their function is to absorb or "accumulate" some of the hydraulic pressure that is intended to apply a clutch pack or band. By limiting the action of what is essentially a "shock absorber" for each shift, we are able to further reduce clutch lock up time and shift lag at wide open throttle.

 

The end result is that shift time is reduced by 30 to 80%, depending on the amount of acceptable shift feel and the intended application. The clamping force that is required to apply the clutches and bands is increased by 30 to 40% at full throttle. Flow through the cooler and lube circuit is increased and the converter clutch application time is also reduced.

 

Transmission and valve body upgrades are not only for American made vehicles anymore. Increased performance and more efficient shifting is now available for vehicles of almost every manufacturer thanks to the few companies that are willing to do the research and development work required for this rapidly growing segment of the automotive aftermarket. For more information, please follow this link: Toyota Modified Valve Body

 

 

-John Lombardo, IPT Performance Transmissions

 

______________________________________________________________________________________

 

 

Author Bio: John Lombardo, a.k.a. Transdude, is owner of IPT Performance Transmissions and has been in the transmission and high performance industry for over 20 years. Visit his website- http://www.importperformancetrans.com for more drivetrain information articles and a wide selection of high performance items.

IPT tech info, specials and a $25 coupon via email

 

 

**This free reprint article is available for use in ezines,

forums, websites and blogs on the condition that the article

is not altered and the resource box remains intact with all

hyperlinks activated. If this article is reproduced an

email to the author with a link to its location is greatly

appreciated- john@ipttrans.com

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It can be done in less time. I spoke with Anthony (I think I got it right) there who does the job. If you schedule in advance and get there by like 7am and can spend the day there, it can be done. Getting there early allows stuff to cool down for them. They'd rather have 2 days but can do it in less.
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It can be done in less time. I spoke with Anthony (I think I got it right) there who does the job. If you schedule in advance and get there by like 7am and can spend the day there, it can be done. Getting there early allows stuff to cool down for them. They'd rather have 2 days but can do it in less.

i had been talking with John via phone about mine and he understood the necessity to get it back to me. here, there is no such thing as NEXT or SAME DAY delivery, especially to/from East Coast. he got mine done the same day and shipped out later that afternoon. But I sent him the VB and Solenoids only while my car sat in the back of the dealership....i had a week to do it since i could only work on the car after hours in the shop (or i'd have to pay the dealership for labor) on Saturdays. i had to rent a car for a week and got stuck with a lame ass Ford Taurus that didn't even have a CD Player!!!! :( from shipping it out to receiving it back took about 4.5 days by the time i got the part. That was fine because i just wanted to make sure i had it before that saturday to put the car back together. once we did, we (the tech, hubby, and i) took it for a spin. it felt like a whole new car and well.... it was still icy out and he (the tech) got us sideways on the back roads, no slipping gears and the car HAULED ASS. :D

Wiggle wiggle wiggle wiggle wiggle yeah!!!
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