HOW TO Raise ATX Line Pressure (firm shifts)

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VortecGT

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First off i'm going to suggest if you are not willing to rebuilt or replace your transmission sooner than later DO NOT TRY THIS! I AM NOT RESPONSIBLE FOR ANY DAMAGE CAUSED!

All I did was disconnect the EPC solenoid from the PCM, which is what controls the line pressure. I ran a switch as you do not want to have this disconnected all the time! (Only turn it on when needed!:naughty:)

First you will want to remove the airbox and rubber intake inlet, there is one bolt on the side of the car and one on the lower part of the airbox. You will also want to disconnect the MAF and the sensor on the lower part of the airbox.

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Next remove the cruise control module, disconnect it and take the 2 nuts off the strut tower and just move it out of the way.

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Now you have access to the main connector on the top of the transmission it is white. Disconnect it and remove the tape around it. You are looking for the white with yellow stripe colored wire. It may look all yellowish if it is old just don't confuse this with the white with red stripe wire.

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Cut the wire and strip it on both sides. Soder one wire to each end and heat shrink them and then tape up and reinstall everything under the hood. Now run the 2 wires inside the car. There is a nice hole on the drivers side below the brake booster. (I ran mine into the center console.) Note the other two wires are for my overdrive switch disregard those.

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Now connent the wires it a switch and mount it somewhere in the car.

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THATS IT!

NOTE On a 1993 ATX with a stock pcm the OD light will not flash. On a 1994 or 1995 the OD light will flash.

ALSO I DO NOT RECOMMEND THIS ON A 1993 AS THE TRANSMISSION IS NOT AS STRONG! (THIS IS WHAT CAUSED MY 1ST TRANS FAILURE DUE TO THE ALUMINUM FORWARD CLUTCH PISTON CRACKING!)

DO NOT RUN YOUR CAR WITH THE EPC DISCONNECTED FOR LONG PERIODS OF TIME (ONLY USE IT WHEN NEEDED!)

AGAIN I AM NOT RESPONSIBLE FOR ANY DAMAGE TO YOUR CAR OR TRANSMISSION! DO AT YOUR OWN RISK!
 

whiteguy3

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That's definitely a way of achieving better shifts I just don't know that I would do it honestly. Get a tweecer. But do you know the benefits or negatives of doing this?

I assume when disconnected it runs at full pressure correct?

Also, You will find out real quick why you need an aftermarket front mount with max line pressures.
 
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VortecGT

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That's definitely a way of achieving better shifts I just don't know that I would do it honestly. Get a tweecer. But do you know the benefits or negatives of doing this?

I assume when disconnected it runs at full pressure correct?

Also, You will find out real quick why you need an aftermarket front mount with max line pressures.

A tweercar would be the right way to do this. As I do not have the funds for it this is just to have fun in the meantime! And yes the transmission will run at full line pressure and i'm sure it's not good for it! I'm going to do a 0-60 test some time soon and see how this affects it.
 
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