I posted in the tranny forum and recieved no response, so....Aside from the Trans-go kit, whta can I do to firm up my shifts....my shifts just feel way too long and "slushy" and I feel like I lose a lot of acceleration time.

 

Without doing a TransGo kit it will take some research. By drilling out a few holes in the spacer plate, installing a larger servo (553) and a larger boost valve, the transmission will shift quicker & firmer. Getting a 553 servo should be easy as many V8 folks remove them to upgrade to the 093 (Vette) servo (offer ten bucks for one).

For a larger boost valve get the GM B-body fix kit that also includes a new 3-4 upshift valve & sleeve. This valve will allow the trans to hold OD at WOT. GM #8673948. Includes spacer plate gaskets and a pan gasket too.

For which holes to drill out and to what size there are several posts on the tranny board that cover just this. Some additional info can be found with a Web Google search.

Most folks on the trans board would have just said to use a TransGo kit. Without that option I can see why the response rate was low.

I installed a custom TransGo reprogramming kit along with the GM b-body 3-4 valve. It is sweet, shifts great, less filling, and holds 4th at WOT (along with any gear I choose).

RBob.

 

Start by adjusting the TV cable. A loose TV cable will translate into sloppy soft early and late shifts. https://www.thirdgen.org/newdesign/tech/detent.shtml

If that doesnt do it then you need to make some internal adjustments. You can use parts of a B&M kit $30 to firm up shifts if your not into reprograming your entire valve body but be warned you may do damage to your transmission if you install the Street/Strip setup, the heavy duity isnt bad but it doesent fix problems like the transgo kit does.

 

I'll try the TV cable, but I was hoping there'd be other things I could do without actually going into the tranny, oh well.

 

The B&M Shift Improver kit is nice, it has really nice shifts. It comes with springs and stuff. I dont know how it works, but it does. And at a very cheap price.

 

well, i was kinda forced into getting mine rebuilt when it died after havign a new engine put in. I asked the shop to put in the vette servo and upgraded boost valve, and they did both, plus an old transgo kit they had for free...The vette servo was actually very cheap, not sure on the boost valve, can't remember the price...but the whole rebuild was a little more than 700 dollars, and it shifts like a champ. a neck breakin, tire chirpin, champ.

 

That's the problem; it does it for cheap... supposedly it winds up being more harsh on the trans. I've got the B&M Shift Improver kit; I put it in myself; but after I rebuild this trans, I'll be putting in the TransGo one- it's the one the pro's use. Skip the B&M kit altogether.

All you need is the skinny ATSG service manual for your 700r4 (or the http://www.helminc.com book, the trans section is what the ATSG manual is) and you're all set to dive into the trans. Just keep everything clean, and don't rush, and read the directions twice, and you'll be fine.

If you don't have the GM/Helm Service Manual (and I can't imagine why you wouldn't??) then buy the ATSG book from here: http://www.atsg.biz/ Or buy it from http://www.northernautoparts.com for a buck or two cheaper.

 

Hey Tom, which setup did you install, S/S or heavy duity?


Anyway for anyone cosidering the B&M kit.

Dont install the S/S setup HD only. Only use one spacer in each accumulator unless you want your transmission to have reduced life and holes in the seperator plate. (Ive seen 5 with holes from B&M accumulator spacers) Use the blue in the 3-4 accumulator and the red in the 1-2. With the pressure regulator assembly you need make sure to install correctly, if you feel intimitaded leave it alone. It doesent increase the pressure that much according to my trans guy I use when I need help. Never install the line bias blocker rod and make sure to re-assemble the parts correctly. Ive done a few transmissions with this configuration and the way B&M tells you to. My way is less harsh with firm fairly equal shifts, B&M's way gives you a harsh 1-2 shift that get annoying after a week.

 

Ah, see, yeah, I installed the street/strip version, with the accumulator shimmed all the way up (I had to actually file the spacers down because they were about 1/8th too high!), and the blocker rod. And getting that snap ring out was a pain... barely reached it with the snap ring pliers I have.

How did the holes wind up in the separator plate? B/c of all the pressure concentrated on the small "footprint" of the spacers? I can't remember if the spacers pressed against the separator plate, or if the pistons did.

This 3rd trans wasn't rebuilt too well; I've been bitching about it for years now. It slips in 2nd under light throttle, I think the 2-4 apply piston is too short; I bet the guy didn't measure it with that depth tool. It won't slip it if I have the stick in 2nd- and as you know, that almost doubles the line pressure inside the trans- and I think that Slams the 2/4 apply piston further. Lately it's been slipping in 4th, too.

Hopefully I've got a line on an old car for cheap that runs great; it's always been a pain doing things to my car b/c it's my only car to get around in. But if I get that other car, I can actually start on my lonnnng list- one item is rebuilding the trans. I figure I can't do much worse than the other two morons did- And I intend to do better!

I'll probably rebuild this '86, because I've heard stories about people not being able to downshift their 700r4's... as in, they don't have full control. I have full control of mine; so I wonder if the 87-up trannies had an extra mechanism (possibly the auxiliary valve body?) to prevent downshifts. Either that or everyone I've heard from has tried to drop the motor into 1st when they're doing 70 on the highway in 4th?

 

Ahh the neck snapper kit.


Actually its the springs that wear into the plate from the increased pressure of the spacers, not fun stuff finding an exact replacment plate.

Ive heard about people not gaining full controll over shifts but havent figured it out as of yet. Usually removal of the MTV spring allows full controll but people on this board still say after removal it still manully shifted to second. Its funny because they all had different year transmissions some 88+ some older. I know removal of the spring solved the problem with the 82 caprice tranny I had in my car. Ive been digging around for a VB fluid diaghram but apperently its top secret CIA, FBI, HLS, NSA eyes only information. It would be nice to have this info to talor shifts to personal prefrences.

 

As long as I'm easy on the throttle, I don't notice the harsh 1-2 shift- besides, that's what the headrest is for!

The springs wear thru the plate? I don't have any springs left in my accumulator... it's just spacers in there now. The accumulator was meant to cushion the 1-2 shift, right? (Extra delay for clutches to engage, since the accumulator had to fill with fluid to compress the spring and move the piston?)