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joe g
02-08-2007, 09:37 AM
I have installed a 700R4 in my 69 Camaro. I have a ZZ430 (clone) and 3.55 gears, 27" tires.
In drive or OD at full throttle it shifts 1-2 at 5500 rpm (perfect) but 2-3 is at 4800 rpm. TV cable is right; BTO EZ setup. I have verified full throttle and idle positions of cable with the pan off. Downshifts, part throttle upshifts are fine.
I had a Transgo shift kit in it but it shifted too harsh and at too high of rpm at light throttle so I put a stock valve body back on it. Left the sevos in place.
I am thinking of changing the governor, but don't want to overrev for the 1-2 shift.
Any suggestions on how to raise just the 2-3 shift point at WOT?

Thanks
joe

Jayco_Automotive
02-09-2007, 04:11 PM
what transgo shift kit did you have, did you install it yourself, i just need this info to determine approximate psi on line and throttle pressure so to make an intelligent calculated response... also the shift kit should be tailored to shift crisply and not harshly...pm with the info and i can help you fix this problem, i have built literally hundreds of these transmissions. So im sure we can resolve this issue

joe g
02-11-2007, 01:52 AM
Thanks! I have sent you a PM (it's pretty long) :)

joe

joe g
02-11-2007, 02:00 AM
test

joe g
02-28-2007, 08:42 PM
I am still looking for some advice on this.

Some background:
I bought the tranny from a local contact; it was freshly done for his street/strip car. Couldn't turn it down. It has about a 2200 stall.
After I installed it I was having trouble with light throttle shifting being at too high of rpm and too harsh. It would not upshift below about 2300 rpm; even then I had to back off the throttle to let it shift. I thought I would install the Transgo kit so I would know for sure what was in it.
I installed the BTO TV EZ setup and have verified full TV travel with the pan off.
I installed a pressure gauge when I installed the tranny. Here are the readings:

P = 75#
R = 125#
N = 75#
OD = 75# idle - 150# full throttle while driving
D = 75# idle - 150# full throttle while driving
2 = 200# idle - no change with throttle while driving
1 = 200# idle - no change with throttle while driving

I installed the shift kit from Transgo. Followed instructions exactly (good video, too). I drilled and plugged the valve body/separator plate where it said to. I plugged the 4th accumulator also (like the kit said to). I picked the softer version (installed one washer instead of 2) for the 2nd accumulator for a softer shift.

That made the problem worse.

Pressure readings are the same as before but the problem was worse.
Now it wouldn't up shift below 2800 rpm at very light throttle; about 3500 rpm at 1/4 throttle. Full throttle 1-2 still at 5500 rpm. The shift was a bit softer, though.

I had called Transgo before I installed the kit to try and understand what the kit actually did. They were not really very helpful other than saying the kit would not change light throttle shift points. (But it sure did!).

So I installed a bone stock valve body from an 89 3/4 ton pickup. It drives much better. It is still a bit high at light throttle but liveable. Full throttle 1-2 at 5500 rpm; 2-3 at 4800 rpm. Downshifts are good. It will do a 2 gear downshift when needed. Shifts are quite firm, but not as harsh as before.
If I could just get the 2-3 shift point up I think it would be much more satisfying.


Thanks for any thoughts

joe

6'9"Witha69
03-01-2007, 09:34 AM
You changed the spring when you installed the BTO cable setup, right? Have you played with their adjustments on the carb for light throttle pressure? Your OD/D idle numbers look low and the 1/2 idle looks high. Have you called BTO to have them verify your readings?

AndyD
03-01-2007, 01:04 PM
not to hyjack the thread, but I have a question about my 7004 aswell.

I had it built last year, and still works well. The people who put it together for me said they put a billet servo in, wide band and some heavy duty clutch plates and upped the line pressures as much as they could. (Please excuse my ignorance towards transmissions if any shows through).
One thing is tho that it will never downshift into first when in drive. i could mat the peddle as soon as the tranny shifts from 1st to 2nd, and it will stay in 2nd. The TV cable is set up right and shifts at around 5500-5800 when shifting from 1st to 2nd. What could be causeing this?

Jayco_Automotive
03-01-2007, 08:40 PM
not to hyjack the thread, but I have a question about my 7004 aswell.

I had it built last year, and still works well. The people who put it together for me said they put a billet servo in, wide band and some heavy duty clutch plates and upped the line pressures as much as they could. (Please excuse my ignorance towards transmissions if any shows through).
One thing is tho that it will never downshift into first when in drive. i could mat the peddle as soon as the tranny shifts from 1st to 2nd, and it will stay in 2nd. The TV cable is set up right and shifts at around 5500-5800 when shifting from 1st to 2nd. What could be causeing this?

will it go into first when selected manually???

joe g
03-01-2007, 11:50 PM
You changed the spring when you installed the BTO cable setup, right? Have you played with their adjustments on the carb for light throttle pressure? Your OD/D idle numbers look low and the 1/2 idle looks high. Have you called BTO to have them verify your readings?

I did put in the BTO TV spring and have played with the adjusment; doesn't have much, if any, effect. BTO hasn't been much help other than to say it all sounds fine........

joe

AndyD
03-02-2007, 08:17 AM
will it go into first when selected manually???

yeah, it will stay in first when shifted to low gear, and I can downshift it into first from second. it just wont act as "automatic" as it should, and wont downshift from second.

100MPHWHEELSPINNER
03-06-2007, 02:13 PM
Call Bowler 618.943.4856 ask for mark.

Jayco_Automotive
03-06-2007, 03:44 PM
this is going to sound insane BUT if the valve bdy bolts were installed in the the wrong holes since a few of them are different lenghts it could cause it to shift into second and not shift down to first, ill post more later

AndyD
03-07-2007, 03:36 PM
yeah, like i said, i can shift the tranmission into 1st manually, but it will never downshift into first by itself.

joe g
04-07-2007, 06:16 AM
this is going to sound insane BUT if the valve bdy bolts were installed in the the wrong holes since a few of them are different lenghts it could cause it to shift into second and not shift down to first, ill post more later

I didn't find this info in my manual......I don't remember different length bolts, except for acopuple that wouldn't fit any place else.....

joe

fastercar68
05-24-2007, 10:14 PM
Hey Joe,

This all sounds very familiar to me. My main problem was that it didn't shift automatically at WOT - I had to let off a bit in order to pick up the next gear. I kept taking it back to the shop that built it over and over (although they worked with me, the repeated trips for shift quality ceased to be covered under the new transmission policy) Then they went out of business. I found a new shop in Walnut Creek and they took a stab at it. They gave one try at fixing the other shop's valve body and then threw in the towel and installed a new Transgo. That cleared up about 90% of the unwanted symptoms. On occasion it would miss a shift at WOT.

Then last fall after a day at ThunderHill road course, the trans pump failed. I took it back to them and they did a full rebuild. It's now 100% perfect. Manual shifting, auto shifting, WOT, downshifts, 2-gear downshifts - it's all good. Wasn't cheap (same price as having one built) but at least I don't have to keep running it back to the shop for more tweaking.

Sounds like you like to do your own work, let me know if you want any more info.

Ozzie