This is for the experienced guys (Leo, Pro Built, Jay, and others). I don't want you guys to give away any trade secrets here , but I'd like to get some hints and maybe some tricks you guys do when installing the kit. Should I do it strictly in accordance with the instructions and movie?

I just got a super awesome deal on eBay for the full reprogramming kit ($26) and I'm ecstatic and psyched! I have installed one of these before on my wife's '88 Blazer a few years back. It was a full rebuild with Transgo kit installation I got from JC Whitney. Problem was that after I did the install, it shifted really hard and had some vibration. I don't want the same thing on this tranny. I want firm shifts, not neck snapping shifts. Right now the Berlie shifts great when cold but the 1-2 and 2-3 shifts when warm are a little squishy. Fluid was just changed and nothing but a little sludge in the pan. I also have a Corvette servo I'm going to install while I'm doing the kit. That "should" clean up the 1-2 shift, eh?

Thanks guys,

 

I'm installing the TransGo SK 700-G shift kit, in a 1987 aux. valve body, and here are some comments from the total novice point of view:

The instruction is written for a professional who knows how the trans work in detail, but as a newcomer in the field I would have preferred the instructions to tell not only what to do, but why you do it.
What function each mod have on trans performance. That would make room for better understanding and less confusion.

I'll make a list of my questions:

Servo mod: Kit doesn't include the cover o-ring which you will have to cut during disassembly.
(It didn't include thimble filters either although they are specified on the packing list)
It tells you to discard the 2.piston snap ring (doesn't say why). This reduced the slack and caused my band to bind. I got it verified that it's ok to use the snap ring.

Kit gives a range for each hole diameter when drilling the spacer plate holes, but doesn't tell the purpose of each hole, nor how using low-high end of the range will affect trans operation.
(Except hole B (2. feed), when it you can choose comfort, normal or short)

I was really confused by the 3-4 accumulator mod, since it reverse the piston and put a new spring on the other side. (Doesn't explicitly tell what to do with the original spring, assume it should be left out.)
After looking into this I realized that what this mod does is eliminating the accumulator.

I had the checkball 10 (TV exhaust), but this is not shown in the kit instructions. (Assume it should be left out, I also just found a reference to this in the ATSG manual)

 

I'm also a novice, so I can't provide any complete answers, but these links can perhaps be of some interest.

Here is a picture showing at least the holes for the shift valves:
http://www.transonline.com/electroPu...fm?pageID=2437

The larger these holes are, the shorter (harder) the shifts will be. It is generally recommended to be very conservative regarding the hole size. You can always enlarge the holes later, if you want even harder shifts, but it is more difficult to go the other way... Larger boost valves, Corvette servo, blocked accumulators or stiffer accumulator springs will also give harder shifts.

Here is a picture showing the check ball locations:
http://www.transonline.com/electroPu...fm?pageID=1484

 

GregN, give me a call at 800 7763288 and I will explain to you on what is happening & why?. And give you the necessary modifications to do this right, without the harsh 1-2 part throttle shifts or other side effects.

 

Dana at PB,

Thanks for talking with me on the phone today. I was able to find the code on the tranny and, yes, it is in fact an '84. Code is 4YP069A. I'll give you a call again when I get the kit in and we'll talk trannies.

Thanks,

 

Thanks JPiroc87, that site was really good!

And greetings from Norway. We have had a very mild winter and my car has been on the road most of the time. But now it's snowing so I wont be able to test the TransGo installation for a while....

 

We have had an on-off winter here this year. One week raining and the next -20C. I am about to install the High Performance TransGo kit, along with the boost valves, servo and accumulator setup, but not for another month or so. I need to move the car to another garage, which is some 30 miles away, partly along icy roads and I only have the summer tires (I don't drive the car in winter).

Did you block the 3-4 accumulator by the way? I am not sure what to do with that since I also intend to install the WOT 3-4 upshift valve (GM) and I still have the stock 12" converter. The TransGo 700-2&3 kit instruction tells me to block the hole in the case, but I think I will keep the hole open and install shims under the piston to start with. I can then block the hole later, or install the piston against the separator plate, if I want firmer 3-4 shifts. The 700-2&3 instruction recommends 0.156 - 0.200 for the 4th feed hole, while the SK 700-Jr instruction recommends 0.110. I plan to go with the larger hole size (not the largest) and that should firm up the shift as well.

 

Apparently they use different ways of eliminating the 3-4 accumulator, why I don't know.
In my SK700-G Shift kit it's done by reversing the piston/spring and use a heavy spring supplied with the kit. See image.
I haven't installed the 3-4 WOT option.

As far as the 4th feed hole my kit doesn't specify any changes. The holes altered are:
07 Lo 1. feed
14 2. clutch
43 3. feed
44 3-2 high speed
45 2. speed
46 3. clutch exhaust

I tried to locate the no.47 4. feed hole in the ATSG spacer plate drawing, but it's not there, maybe a misprint?
Are you installing the large 4th piston also?

 

The installation of the High Performance kit includes quite a lot of drilling and plugging. If you are interested, I can send you the installation instruction (scanned 1.2 Mb PDF-file).

Unfortunately I have no information about how each change affects different things and for that reason I will have to follow the instructions to the letter. Maybe GregN has some more input after talking to Dana? I think I will deviate from the instruction on one point though: I will not eliminate the 3-4 accumulator right away. I will test how the shift feels with a stiff spring, a couple of fender washers under the piston and a 4.5 mm feed hole. For all other holes I will use the minimum recommended diameter (if I can find exactly matching drill bits from somewhere). The recommended hole diameters are comparably large with the High Performance kit anyway, except for the 1-2 hole.

Didn’t the Corvettes have the WOT 3-4 upshift feature as standard? Or was it just no 4-3 downshift above 75-85 mph?
I will keep the standard 4th servo piston.

 

Yes, thanks, it would be interesting to see the instructions.
I have scanned the Transgo 700-G also if you are interested.

The figures I gave for the holes are the ATSG reference number, not the diameter.

 

Can anyone help on a sk279 shift kit. Installed but wont go into any gear.