700R4 Shift Points

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custodian

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I adjusted my TV cable and after test driving I noticed the shift point for 1-2 is around 10-15mph, 2-3 is around 25-30 mph, 3-4 is around 45-50,and this is driving with a light acceleration. The kick down (passing) worked and it did downshift. Doing a more moderate acceleration the shift points were 15-20mph, 25-30mph and 40-45mph. I'm not sure how accurate the speedometer is.

The rear end is a 3.08 and running 15" tires.

Do these shift points sound right or close to where it should be?
 

Vbb199

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I guess the most obvious question is, with truck off, throttle blades at WOT, is the TV cable TIGHT?

I would say,
Light acceleration 1st-2nd is like, 15-20, WOT would shift at 30-35 mph 1st-2nd
 

custodian

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I guess the most obvious question is, with truck off, throttle blades at WOT, is the TV cable TIGHT?

I would say,
Light acceleration 1st-2nd is like, 15-20, WOT would shift at 30-35 mph 1st-2nd

Cable is tight. I haven't done WOT acceleration yet.
 

Vbb199

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Cable is tight. I haven't done WOT acceleration yet.

From your previously recorded data, you seem like youre on the right track as is.

Theres also line pressures you can tune the TV cable to for a 700r4 with a gauge.
 

Matt69olds

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It important to make sure the carb goes to WOT with the gas pedal. Make sure the floor mat, linkage flex,etc is keeping the carb from opening all the way.

Btw, the shift points are pretty close to textbook specs.
 

custodian

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It important to make sure the carb goes to WOT with the gas pedal. Make sure the floor mat, linkage flex,etc is keeping the carb from opening all the way.

Btw, the shift points are pretty close to textbook specs.

I might just leave it as it is or do another TV cable setup to see if it changes. This trans was rebuilt with the Red Eagle disc and steels. The truck now has 15 miles on the build.
 

Ricko1966

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I no longer trust the is the cable tight method, too many other variables, is the geometry right etc.You've got serious coin wrapped up in this and no miles yet. Get some gauges and check your pressures.
 
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Matt69olds

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A line pressure check is always better than guessing.

Have a helper sit in the seat, mash the throttle to the floor. Does the carb also go to WOT? If not, bend the throttle linkage back until it does. Then make sure the TV cable adjustment is correct.

Line pressure in drive should be around 90psi at idle. It should also instantly increase with the slightest throttle movement. Maximum line pressure will depend a lot on what boost valve is in the pump, what pressure regulator spring is installed, pump condition, etc but I would expect a minimum of around 240 at max TV.
 

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