Torqueshift
Elder User
Joined: Nov 2003
Posts: 987
Likes: 3
From: Bass Lake, CA
Originally Posted by PSD 60L Fx4
That's the job of the VFS soleniods. The lines going to the clutch drums are large; the VFS varies its orfice size according to the incoming duty cycle to the solenoid.
When tuning these things, there are two variables to play with. You have the actual pressure, and the rate of opening of the valve. Both play a part in high performance shifting- to make it faster, you have to raise the DC on the solenoid. To make it harder (and correspondingly more holding force) you have to raise the pressure tables.
And yes, in any modern tranny where the shift is commanded is not neccesarily where it will occur due to the time it requires to fill the clutch. There are PCM calculations dealing with this...I had to make some modifications to mine when I changed to the Suncoast clutches.
When tuning these things, there are two variables to play with. You have the actual pressure, and the rate of opening of the valve. Both play a part in high performance shifting- to make it faster, you have to raise the DC on the solenoid. To make it harder (and correspondingly more holding force) you have to raise the pressure tables.
And yes, in any modern tranny where the shift is commanded is not neccesarily where it will occur due to the time it requires to fill the clutch. There are PCM calculations dealing with this...I had to make some modifications to mine when I changed to the Suncoast clutches.
maybe the orifice feed hole in the shafts are larger, and the solenoids themselves are where the variable diameter orifice lies?
Former Vendor
Joined: Mar 2004
Posts: 4,362
Likes: 3
From: Hendersonville, NC
Originally Posted by mattsf250
ahhhhhh, rock on. thats a sweat deal..... im still stuck in the mindset of the old fmx style trannies (fmx, aod, aode, 4r70w) and the c4/c6 units...... being the 5r110w is a derivitive of the c6 (in a way) i ASSumed they operated in much the same way. variable orifices onside of an input, or output shaft is quite perplexing, prolly still not gettin it 100%.
maybe the orifice feed hole in the shafts are larger, and the solenoids themselves are where the variable diameter orifice lies?
maybe the orifice feed hole in the shafts are larger, and the solenoids themselves are where the variable diameter orifice lies?
The whole purpose of such is to transfer more of the operation of the transmission to the PCM and away from moving mechanical parts. May not be much for reliability at this point in the life of the idea, but down the road I would imagine it will be a good thing.
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