Keep in mind that as you raise line pressure in the trans you raise the amount of heat generated and you accerate the wear on the pump.

Gil Youngers shift kits are designed to correct certain areas of a trans operation , not make the trans a slam shifter. He has bumped up the shift firmness in some of his kits due to the demand from people.

Gil made a comment years ago( I may not quote him exactly here) when asked :"what is a good shift?" He responded with " A good shift is one you can really say nothing about. It's not too hard or soft"

 

But isn't the accumualator downstream from the pump? So if you're boosting the pressure within the accumulator valve body, the pump is none the wiser. Now I would agree that using electronics alone (a chip or electronic "clip on" so called shift improver) could cause problems if you tried to boost it too much. I still have my Superchip in and I'm not too concerned about the satndard program.

I'm no tranny expert, just reading and picking up what I can.

By the way, as much of a test as it can be, I dropped the pan when it was fully hot and the fluid was warm to the touch. I've gotten better at dropping it (3 times in as many days) but I still had it on my hands and arms a little. Even the pan was just "warm". Now I was concerned about the crackling cat converter above my head.

 

The accumilators in the trans can only " see" the pressure that the pump generates and the Line Pressure regulator system sends to the trans valve bodies from the pump.

My words of caution was If you add larger boost valves, stiffer pressure regulator spring and alter the programing for "operating line" pressure, the increase will generate more heat and wear on the pump.

Raising the "pressure in the accumilators" is with the use of stronger springs to resist the incoming apply oil pressure. It is the same thing as stiffer valve rates in a shock asborber on the suspension of a vehicle.

The enlarging of the holes in the separator plates will increase the flow to shift valves and clutch packs. When you open a hole up 30% you increase the oil flow by double through that hole if the flow and pressure behind the hole remain constant.

Sometimes the hole that is opened up is an exhausting hole for a clutch pack or band that is "comin off". You must be careful there to follow guidelines of the instructions to avoid a "flare shift' caused by bad shift timing with incorrectly sized holes that must function in harmony to produce a good clean up shift or down shift.

 

Thought I would post a reply now that the Transgo and line valve mods are done on the 4R100 transmission for my L.

Shifts are better than stock, but just noticably so.

But this is what I want to share with you. For those of you who were sweating what hole sizes to drill for the 1-2, 2-3, 3-4 shifts in the accumulator body, I wouldn't worry about it too much. Let me put it this way, in my 2001 L, the holes in the accumulator body were way way bigger than the largest drill bit provided by Transgo. I did not measure them, but they had to be at least 0.25" holes. Obviously I left them alone. Apparently SVT uses different separator plates (with much bigger holes) for the L as compared to all the other trucks that use the 4R100. So I guess my observations back up the observations of Familyride - Increasing the hole size helps, but doesn't dramatically change the shift characteristics.
Hope this helps.
GDG

 

GoDogGo

Thanks for the post, that's interesting. Mine didn't have a seperator plate, just the gasket. I wonder if that's one of the differences?

Noiw that I've been driving mine for a couple of weeks, and got the Amsoil in, I'm loving the shifts! No barking tires but WOW! And towing is just a great. I'm not sure what I was worried about!!

 

Thanks for keeping us informed on your experience. Glad you had positive results with the Transgo kit. Like you, I'll probably keep the chip's standard program and work my way up when I try the Transgo kit soon. Thanks.