Rev Flare into 2nd - 3/4 throttle

[66 Sat]

I know there's a few threads with flaring revs but mine does it only under these circumstances:

3/4 throttle from a stop, there is flare shifting from 1st to 2nd in D.

2nd to 3rd is fine at all times.

Full throttle in D there is no flare at any time.

Manual shifting there is no flare at any time.

Driving "normally" in D there is no flare at any time.

727/318 poly. Transmission was checked and serviced by a shop before it went back into car. It's been like this for over 2 years now - just wondering if it could be causing any damage and if it's an easy diagnosis/fix?

 

[493 Mike]

Excess slippage is never good. Check the KD band adjustment and the throttle pressure linkage first. Then check the pressures. This is all described in the FSM. Good luck!
Mike

 

[66Satellite47]

This needs attention, flare up no good. I suspect the kickdown linkage is slightly out of adjustment.

 

[dvw]

If the kickdown linkage has been modified, the geometry could be wrong. It's possible that there is no throttle pressure increase at part throttle. If its flaring the KD band is more than likely already damaged.
Doug

 

[vance.dykes]

did you check the fluid level ?

 

[66 Sat]

Fluid level is fine so it's not that. Thinking about it last night what I'm experiencing isn't exactly flare, or not what I've had previously when the kickdown wasn't adjusted properly - this feels like an "overshift", it's hard to describe. It's flare but still with acceleration, like clutch slip. I'll take it to the transmission shop and get the guy to come for a drive to show him.

 

[66 Sat]

Well it's definitely a kickdown linkage adjustment issue. I went to see the transmission guy and he said to adjust it carefully and see what happens - with a bit of fiddling I eliminated the 1-2 flare but then had a bit of a woolly 2-3 shift. So I adjusted it again and the 2-3 is fine but 1-2 flared a little on half throttle.
The issue is the geometry and the linkage as said above - the throw on the 4 barrel Holley is probably different to the original 2 barrel carb, plus there's lateral slack in the many joints in the linkage.
At least I know the transmission is ok - just more fine tuning required and some work tightening up the linkage so the throttle opening moves the lever in the right direction at all times.

 

[66Satellite47]

Get rid of the flare up on the 1-2 shift or the front band could quickly be damaged.