A forum for discussing applications and implementations of the MegaShift transmission controller code
for the GPIO from B&G. This can control up to 8-speeds and 6 shift solenoids (plus a 16x9 table for controlling a PWM line pressure valve). It has manual and fully automatic modes (16x9 load x speed table), with under and over rev-limit protection, and full data logging of all inputs and outputs (among many other abilities). A TransStim
to test your completed board is also available.
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- Joined: Sun Sep 21, 2014 11:28 am
Anyone got any input on 4L80E line pressures? Infact anyone know what the rise rate should be with throttle position?
I know the standard controller uses TPS for load, and my installation does too (the axis label is wrong). So I'm just interested to know what the standard rise rate is, is it linear with throttle position, or is 100% line pressure achieved at say 50% throttle and it's linear to there. Or does it rise exponentially with throttle position?
I set my lowest row based on the standard line pressure with a closed throttle. So I have about 75psi at 50% duty and 180psi at 100% duty (at idle speed)
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- Joined: Thu Apr 17, 2008 5:19 am
I would just start with full line pressure across the board, and back it off until the shifts each your desired level of softness.
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- Joined: Tue Mar 15, 2011 8:37 am
Mine is set very similar and has been successfully driving well for the past two years. I even did some doodling with pressure values in the low speed and load region to make it feel like a stock cushy box
I've ran it on slicks a few weekends a year and works really well. The "load" should be a function of TPS And RPM if you're using the default table in TunerStudio.
DIY'er with Your help
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- Joined: Fri Aug 15, 2014 7:58 pm