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Discussion Starter #1
I had recently put a B&M 700R4 shift improvement kit on my 85. Drives great around town. I love the way the it takes longer to shift, really sounds good during mid range with my "stingers". But I have noticed one problem. Under WOT the shift from 1st into 2nd, is barely noticeable at all. Now again, during cruise time, the shifts are nice and firm. But from a launch under WOT, the rpm's get to about 4500 and decides to shift, but you dont feel it at all, and really takes away from the run. I dont think its slipping, its not giving that - rev then hook up - feeling. This tranny shop I took it to had given me one diagnosis. And they think that maybe the Seperator Plate Gaskets (or Valve Body gaskets) could be off set a little bit. Not allowing the amount of oil flow to reach the spots needed under heavy pressure. Does this sound right, or do you think I could have not done something right to the accumulator, or pressure regulator, or something? Can you guys help me out before I go taking everything apart again?
 

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I'm not an auto trans specialist by any means, but I thought the purpose of the B&M Shift Kit was to provide a quicker and harder shift, not a smoother and slower shift.

According to their literature ...

http://www.bmracing.com/media/catalog/9.pdf

That site claims that Stage 1 will give you firm, positive shifts, while Stage 2 will give you the quickest, hardest possible shift.

If your transmission is shifting slower, and it sounds like it is, then I think you're going to have to take it apart again.

Steven
 

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I had one, it would rip your head off from 1 to 2, who every put it in, you are a trans shop. Need to take it back apart and found out if there is some thing wrong. If it is the trans shop take it back and have them fix it like the way you wont it. I am not a trans guy by any means, but I due know if done right it will put a smile on your face. Good luck
 

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I have an 85. You should do the B&M Trans Pak insteaad of just the shift kit. The Trans Pak has a shift kit included, but it also changes some springs and things in the valvebody. It's not the rebuild kit, just a step up from the shift kit and is all performed on the valve body. Also you might think about changing the servos while you are at it . There is one for 1-2, and one for fourth. Run you around 75.00 each in summit for those, but worth it because the 85's were weak in that area. After doing those mods on mine, my car will now jump out sideways when shifting from 1-2 if I'm on it good, and it no longer "slides" into fourth like the 700r4's were notorious for, but shifts into it firm like the other gears.
 

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Discussion Starter #5
See the kit did make the 1 to 2 shift a lot harder during any cruising time. It's just under wide open throttle that it seems to glide into that shift. So i would assume that its something wrong while the tranny is under a lot of pressure.
 

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Discussion Starter #6
And yea I did want to do the TransPak instead, but B&M highly didnt recommend it due to the amount of miles that are on the Transmission. Cuz I have quite a bit. They just recommended the Shift Improver Kit because it won't put that much more stress on the bands and clutch packs. But I'll get those nice shifts.
 

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:crazy: Mine had 98,000 on it when I did it. I did replace the servos though and that will save your bands and clutches because it has a larger foot surface and grabs the bands better for LESS slippage. It will actually make your tranny last longer because it will slip less during shifts. I also run a deeper pan from summit, Trick Shift fluid, and a TCI 2500 stall converter. My motor has had a lot of work done to it and it is holding it just fine.
 

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Discussion Starter #8
Alright cool. Did you notice any difference in running that fluid? Because i haven't heard many things about it.
 

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The only difference the fluid makes is it dissapates heat better than normal trans. fluid so it lowers your transmission's temp. by a couple degrees. It also has a nonfoaming additive in it that keeps the fluid from foaming when it gets hot. Good stuff but expensive. $5.00 a quart here. Hurst also makes some called Quick Shift I think is the name of it. It is supposed to do the same thing, but I've never used it. I've always used Trick Shift which is made by B&M.
 
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