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Old 03-08-2013, 12:22 PM
ASE Doc ASE Doc is offline
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That is a very good article. It causes me a little confusion as it seems to counter what I understand about the accumulator valve. I was under the impression that the accumulator valve, in the 700R4 anyway, controls exhaust from the separator plate side of the accumulator. I was given the impression, by someone who's knowledge I place great faith in, that installing a lighter spring allows more accumulator action and therefore produces a milder light throttle shift while producing a firmer full throttle shift. This seems to fit my interpretation of the hydraulic schematic.

The trans had been built with a corvette servo, a stiff accumulator valve spring, and a weird high coil count spring in the 1-2 accumulator that only allowed partial movement. The result was a 1-2 bang shift at light throttle. Above 1/4 throttle, the 1-2 shift was perfect. The 2-3 shift was great at light throttle and full throttle, but was a little soft at mid throttle, thus the stiffer line bias spring to hold line pressure a little better through 3/4 throttle. The trans already had many great upgrades, such as the Sonnax line boost kit with .500 TV boost valve, corvette governor that produced 6,000 rpm full throttle upshifts and allowed me to manual shift at 6,500. The changes I made to the 2nd gear package will, I hope produce a firm but reasonable light throttle 1-2 shift and a rock solid 1-2 shift at any more than 1/3 throttle. For the 2-3 and 3-2 shift I hope for the same thing. I also installed the Transgo high rev springs for the 3-4 clutch to help with high revs in 2nd gear. There are several other upgrades to this new trans that I will list once it's all done and tested. If it doesn't work the way I planned it, I will just have to drop the pan and make changes.

Last edited by ASE Doc; 03-08-2013 at 12:36 PM.
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