c6 coast downshift

I have a 1980 f100 flareside with mild build 466, c6,ati streetmaster converter, 3.50 9" 28" tire, street driven toy. The trans was rebuilt(69 ltd core) , trans go kit, purple stripe modulator. I like everything about the way the trans shift except when I slow to make a turn it dont drop back to second or first as soon as I would like.(under low to mild acceleration) That causes the convert to slip. It appears to drop back to second about 10 mph and low at near 0. It always takes off in low as it should. I did just today swap the governor with one from a 79 150 4x4 truck thinking it should be on the opposite end of spectrum from the LTD. No notable difference with that change even though the valves and spring where different between them.
Any ideas?
thanjs, johnny

I would check the kickdown lever on the Carb. adjustment and set it where it has a cunt hair of slack at full throttle with some one actually pushing the gas pedal to the floor. Also make sure the carb. is opening all the way when you do it.

Where is the modulator set at . Try turning it in 1 turn at a time can make it more sensitive

Gregaust wrote:Where is the modulator set at . Try turning it in 1 turn at a time can make it more sensitive

You can fine tune that way but, be careful because it affects TV pressure.

supervel45 wrote:I would check the kickdown lever on the Carb. adjustment and set it where it has a cunt hair of slack at full throttle with some one actually pushing the gas pedal to the floor. Also make sure the carb. is opening all the way when you do it.

The kickdown lever is adjusted correctly and double checked. Where my problem is the kickdown isn't in play yet.

OK now that you have that checked out or eliminated kickdown lever adjustment and the governor in good working order try the modulator adjustment. The next thing might be a problem in the valve body. Make sure your vacuum line is not cracked and clear. Make sure your modulator diaphram is holding vacuum. Make sure the modulator pin is the correct lenght and that the modulator valve behind it is not sticking. The old trick was to grind a couple of flats in a certain place on the modulator valve so it would not hang up also.

supervel45 wrote:

Gregaust wrote:Where is the modulator set at . Try turning it in 1 turn at a time can make it more sensitive

You can fine tune that way but, be careful because it affects TV pressure.

I realise that . That is the reason I asked where it is set at . Usually most guys fit a new modulator which comes not adjusted and the screw is way out .

supervel45 wrote:
The old trick was to grind a couple of flats in a certain place on the modulator valve so it would not hang up also.

The MOD is not grind flats , It is to put a slight bevel on each end of the spools on the modulator valve . What that does if there is any wear marks or ridge , even very slight in the case . The bevel stops the square edge of the spool catching and sticking

Gregaust wrote:

supervel45 wrote:

Gregaust wrote:Where is the modulator set at . Try turning it in 1 turn at a time can make it more sensitive

You can fine tune that way but, be careful because it affects TV pressure.

I realise that . That is the reason I asked where it is set at . Usually most guys fit a new modulator which comes not adjusted and the screw is way out .

supervel45 wrote:
The old trick was to grind a couple of flats in a certain place on the modulator valve so it would not hang up also.

The MOD is not grind flats , It is to put a slight bevel on each end of the spools on the modulator valve . What that does if there is any wear marks or ridge , even very slight in the case . The bevel stops the square edge of the spool catching and sticking

I may try to post a picture from the Transgo instructions latter but, yes you are correct word is  bevel, I misspoke.