Auto tranny upgrades?

[supraman7mgte]

What type of performance upgrades are available for the auto tranny in a 1991 7MGTE? I want to eventually swap out for the 5 speed,but I still need to get a list of parts needed,aside from the obvious.But I still have to contend with the auto.

 

[suprabad]

I was really hoping you would get some answers on this as I also am interested. I suspect no-one really knows much about the a340e. Appearantly we automatic supra owners are persona non grata... :cry:

 

[americanjebus]

YEA our trannies suck we cant do more than 300 rwhp without burning the thing up.

all that i have seen is a huge tranny cooler (which is what i am doing i got a 15 by 7 front mount transmission cooler on it)

and an upgrade to titanium alloy clutches

and a new flex plate (i need this) and torque converter.

in all its more $$ than a 5sp swap.

damn i want a 5sp i always ask my friends if i can drive their cars cus i hate driving auto.

 

[suprabad]

YEA our trannies suck we cant do more than 300 rwhp without burning the thing up.

...i hate driving auto.

BULLSHIT!

I don't know who... but, I guarantee you someone out there knows how to set up an a340e properly. I hear this crap all the time and I don't buy it.

They (Toyota) use this tranny in alot of applications and I don't think Toyota would so universally use this trans if it were a total p.o.s. (which seems to be the universal thought here at Supramania). This is my first supra but I've been around the car scene and building engines for longer than most of you have been on the planet, so trust me when I say that there is a way and I'll find it. (Forgive me for pulling senority.)

As I understand it the a340e is used in light truck applications so maybe the offroad guys are the ones to talk to about beefing this trans up. I dunno but I'll find out.

If anyone has any doubts about the effectiveness of an auto trans then they need to wake up and look at the fastest classes of many types of racing i.e. Drag racing, World Class Sports Car etc.

One last thought; It takes alot of experience and usually an old dog like me to get through the gears quickly and consistantly. If I had a nickle for every young guy I smoked 'cause he couldn't shift worth a damn, I'd have a big pile of nickels!

Keep driving 5 speeds and I'll keep taking your money.

 

[supraman7mgte]

i think i found one place,its called "level 10" in Jersey...

 

[encomiast]

I personally haven't heard many good things about level10 though.....
There is another company, www.importperformancetrans.com that offers tranny upgrades for our A340Es.
I once emailed them to ask what they do to the tranny and that's what they replied (seems to be some copied'n'pasted mail he sent to a 4Runner user before):

As you probably know, the Toyota 340 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 for a performance application.

The problem is that the original calibration is engineered for driver
comfort rather than ultimate strength. The soft, sliding shifts that are
part of the original design are not appropriate for increased horsepower
applications, towing, off road, racing, etc. These calibration inadequacies
quickly manifest themselves as extremely poor shift quality, and more often
than not, severe damage to the gear box is soon to follow.

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 plate and an intricate series of passages- it is the most complex
part of the most complex part of a 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, 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 operation can be drastically altered
and also customized to the application through modifications to this
component. We have been working with these transmissions for many years.
Most of our development work has been done on the Toyota Supra, which uses a
slightly different configuration of this same transmission. Our modified 340
transmissions are out there handling up to about 700 horsepower and the main
reason that this is possible is because of the modifications to the valve
body that we have developed.

When someone with a 4Runner had found us through the Supra community, we
began working on modifications that were more appropriate for Toyota trucks-
especially those that were needing to handle the additional power that
accompanies the installation of a supercharger. The results were very
favorable and we have become the main source of modified valve bodies among
4Runner and Tacoma owners.

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 trans 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 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 needed. The effect of
this is shifts that are not overly uncomfortable at lower throttle openings,
but at heavy throttle, we can accomplish firm shifts with short clutch
application time and increased clamping force.

An additional benefit of this is increased flow through the transmission
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. This is where some customizing can be done for
the given application, and to some degree, to customer preference.

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 upshifting. Their function is to absorb or "accumulate"
some of the hydraulic pressure that is intended to apply a clutch pack. By
limiting the action of what is essentially a "shock absorber" for each
upshift, 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
customers preference regarding the amount of acceptable shift feel. 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.

There also is a sticky somewhere on SF on how to upgrade the valve body yourself by shimming the valves..... HTH.

 

[tlo86]

http://www.importperformancetrans.com/toyotaauto.shtml#main

i just found this and thought of this thread <3

 

[stakie]

I just mine done, by a local guy (Tinton Falls, New Jersey). Very good work. Guy took the whole tranny apart and rebuilt it. He can rebuild it to your liking. I am very pleased!!!

With a well built tranny, and a good rear end, the sky's the limit!!!

 

[SupraJDS]

I am intrested stakie, pm with a price and more info.

 

[Nick M]

Any body that thinks an automatic sucks, sucks themselves.

Yes, this topic has been covered. And on SF of all places. I even posted a link to somebody running the upgraded A340E on his turbo Tundra. 600 lb/ft of torque if I remember right.

 

[tlo86]

Any body that thinks an automatic sucks, sucks themselves.

Yes, this topic has been covered. And on SF of all places. I even posted a link to somebody running the upgraded A340E on his turbo Tundra. 600 lb/ft of torque if I remember right.

i love the autos myself

 

[ATL88Supra]

i love the autos myself

no boost loss FTW

 

[Zazzn]

you guys do know that the mk4 uses the same trans and BL and SP both make tranny upgrades which will take the trans in to 9's?

Any performance trans shop can put on a valve body and trans cooler which will maek the trans handle 400-500 WHP.

The probelm with the stock trans is the length it takes to shift it takes is so long that the clutch packs get burned up.

My 1991 aristo has the same problem my 2jz is currently outputting about 330 WHP and it's painful every time the tran sshifts because it takes so flipping long that I know it's gonna burn it up.

The key is to get something that isn't super rough on the streets..

anyways BL has the lowdown on the trans check them out they are a few grand but it will never break for normal high hp use.

i've heard mixed things about LVL 10.. Sounds like they just charge alot.

 

[tlo86]

do you have a website for them?

strange it takes so long :x do you have an external cooler? i run my 7m's through 2 coolers... i had the prob with long shifts myself but only when the car was cold, added the second cooler and it helped with that though

 

[Zazzn]

well it's not that long but it's not as fast as it shoudl be for a performance trans.
My volvo trans is quick to change almost instant and it's not rough

www.boostlogic.com
I don't have an external cooler i think the stock one runs off the stock rad.

 

[IJ.]

Been beating the snot out of mine since I got it going and it hasn't missed a beat <fingers crossed>

 

[mwracing]

i would love this upgrade locally.

 

[crisp]

...buried somewhere in my garage is my previous (original) A/T that was BUILT BY HKS AT HKS some 15 years ago. It has an Art Carr converter and all the "trick" HKS internal goodies... but my 4.88:1 rear end gears and a "binding" differential "glazed" the plates and who knows what else. It should be good for 400-500HP range, and KICKED ARSE back when it was in the car... now I have an R154 w/Dual Friction Centerforce that is working well... but BIG LOSS on shifting and boost drop...

I venture to say the auto would be "quicker" with 50-100 less HP, perhaps!


Someday, I'll get it rebuilt and be like I.J.:biglaugh:


(Actually, that's just an on-going dream... er... nightmare that I have as I get OLD and GRUMPY... J/K!)


-crisp

 

[3p141592654]

JDUB has the IPT upgrade. On SM there is a writeup on shimming the accumulators for faster shifting.

 

[suprarich]

Holy old thread bump batman...