On a separator plate on a 4l60e what happens if you drill the holes to the specified sizes on the Transgo SK4L60E paperwork but don't use any of the supplied springs etc.

Does it throw off the timing of the shifts and cause all sorts of issues or just allow more oil to travel to the accumulators and make for hard shifts.

 

A pro builder should probably answer your question, but let me take a shot at it. Since I don't know the SK4L60E instructions, let me answer for the HD2.
in my opinion(!)
The conservative drilling for the 1-2 shift, 2-3 shift should not need any springs.
Drilling the 2-3 shift (3rd feed hole) to .101 should be fine. However, if you go much bigger you probably should install extra servo springs and use the Vette servo. Else you might get a flare or bind during the 2->3 shift. IIRC Dana (PBA) also suggested drilling the servo return hole a bit bigger when using a big feed hole.

Of course, the real question is why are you asking? Is it because the servo is hard to remove in your car? Unless you really want to test my "opinion" and risk the lost time or parts, it is best to install all the parts according to the directions.

 

I was asking out of pure curiosity. The hole size thing interests me and the effects of the springs on the accumation pistons. I would like to have more time and money to mess with it. But questions are cheap. ;-)

 

The Hole size will increase the rate fluid travels to the respective device being applied Quicker clutch application or as mentioned disengagement , Upshift will feel firmer. The springs etc. let you change the accumulation effect making for even quicker firmer shifts. No drilling the holes without the spring would not cause any adverse effects generally just not as much of an effect.
All of these thing together along with line pressure can be used to tailor each shift to your need or desire.

 

Thanks for the great responses. I know there's not as many hours in the days as we would like and your time is valuable so to all that chimed in i appreciate it

I thought of another question. Does using a wide band, let's say a red one, warrant any change in hole size due to more friction material contacting the drum? Normally with a wide band and a sk4l60e kit I just follow the preferred hole sizes anyway amd it seems finebut didn't know if anyone suggests doing anything goes different. 4x4 Trailer hauling is the application