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line pressure on 4l80e

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Old 10-21-2012, 09:34 AM
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Default line pressure on 4l80e

Just wondering what line pressure should be on a 80e with a hd2? I put my stock stall in to make sure it was my converter that went bad, all seems to work good other then the 2-3 wot shift drags a little, when the shift starts the rpm don't hardly drop for a split sec then it locks in solid, IM running 80psi at idle then anywere in boost or wot it's at 150 psi. Is this normal? Or should it be higher?
Old 10-21-2012, 09:41 AM
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Jake I like to see about 30-50 psi more at wot when I dyno a trans or adjust one in the vehicle. You can adjust the force motor to achieve this. But be careful when doing this. A 1/4 turn on the screw is all I would do at one time. The 2-3 shift is a little lazy on these units from when the command takes place to when it actually happens. I have used the dh2 kit for many builds on these units and that is something that I noticed while dyno testing these units. So I would say that this is normal. HTH Vince
Old 10-21-2012, 01:05 PM
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Thanks Vince, I'll look into this and try getting it adjusted a little closer to 200.
Old 10-21-2012, 01:55 PM
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My builder wants 180 minimum at WOT, between 190-200 is what he wants to see.
Old 10-23-2012, 07:26 PM
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okay so I drop the pan tonight and adjusted the force motor a quarter turn like said, now I have a 125 PSI idle and it pretty much stay there the whole time, wot flickers between 125 and 150. I guess this is all the pressure it can make, do I have a hydraulic leak somewhere? or is there something else that's a limiting my pressure?
Old 10-23-2012, 10:51 PM
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That's too high at idle, and too low at WOT. Something isn't right, but I am not the right guy to tell you where to look. Have you talked to the builder yet?
Old 10-24-2012, 08:25 AM
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The builder is me lol. I've been running it for 6 months this way I just never noticed the laggy shift till I put the stock converter in it, the 9.5in converter was to loose to tell what it was really doing. Every thing works fine the only reason I intalled the gauge was cause of the converter problem.. I just wana make sure everything is right before installing a 1200 dollar converter.
Old 10-24-2012, 12:21 PM
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anyone have any ideas what else I could try or do when I take the pan back off?
Old 10-24-2012, 07:36 PM
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Adjust in your tune. Lower your base pressure table by increasing the numbers 15 percent or so, then raise shift pressures 10 percent at a time.
Old 10-25-2012, 10:14 PM
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I would pull the main harness connecter with a pressure gauge on the trans to verify max wot pressure. This will tell you if its trans or tune related. Might have to bring the idle up some to get an accurate reading. Just an idea.


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