HI. Is there anything speciel about the stroke and angle of the TV cable on 1993 4L60 (th700r4) transmission from a Z28 Camaro, one year only LT1 motor and with th700r4 and a TV cable, or is the cable setup just like on all other cars with th700r4?

I have this 1993 4L60 from a Z28 paired to a gen1 small block with a Q-jet carb. Have made my own brackets for the TV cable, precisely following the recipes found online, but ended up with soft very early shift points at normal easy driving, yes I have rise of line pressure just tapping the accelerator. Trying to solve this problem I found out that changing the angle of the cable, so that it pulls more aggressively early on of the travel of the accelerator, the shift comes later with a much better feeling. But still not perfect, OD comes in way to early.

This makes me wonder is there anything special about this one year only TV cable setup on a LT1 motor. Is the distance between center of throttle shaft and pin for TV cable different from other th700r4 setups to give another amount of stroke of the cable. Or perhaps the angle of the cable and arm on the throttle shaft is different from other cars with th700r4, to compensate for the characteristic of the LT1 and its throttle body?

If anybody have any knowledge of this issue, i will be very thankful.
If one of this forums members owns a 1993 Camaro Z28, and would spend 10 min. measuring the distance between center of throttle shaft and center of pin to TV cable and confirm the distance is in the neighborhood of 1.094 to 1.125 like other th700r4 setups ( found online ) I would really predicated it.

Thanks in advance

 

There was a really good thread about TV cables/ brackets on thirdgen.org awhile back, and regardless of throttle ;body/ cable/ brackets, the actual TV valve in the transmission always has the same stroke.

When you are at wide open throttle, can you still pull any more movement out of the cable?

 

As mentioned the TV internally will all have the same stroke. and ideally and should be stock on the throttle body/carb stock. You get changes when non stock carb or throttle body is changed.
You can ajjust The TV cable one of two ways, One the presure guage but that might vary if stiffer throttle spring was used in build and other changes.
The other and preferrer to me is to physically note the point at which the internal lever just contacts the throttle plunger, Then work out geometry so that by WOT it is fully depressed. i also remove some material from end of the throttle valve sleeve to allow a bit more travel and ajustability. With stock TV SPRING-LINE PRESURE- CARB- THROTTLE BODY this should not be nessesary , You set up so its max pulled at WOT and the rest should take care of itself. Of ocurse some do use the TV to help set up shift points with lower gears, But not the right or ideal way. That if better done with the govenor with methods ranging from weights and springs to if you dont need a huge change the photo below depending what springs you can find ratio stiff wise, That method will tend to have a greater and greater affect as throttle is greater .
But the spring regardless of stiffness must fully compress into the hole in GOV valve.

 

Thanks for comments and advise.
Valuable info about all th700r4 and 4L60 TV systems being the same internally. Maybe it is just my transmission that acts strange?
GM performanceparts re-manufactured 1993 Camaro Z28 4L60 code 3FMM purchased some 25 years ago, never used, just been laying on a shelf until now.
Home made adjustable brackets for universal TV cable. On the arm on carb, the distance between center of throttle shaft and pin for cable is adjustable. The angle between cable and bracket on carb is also adjustable.
I have checked that the cable can depress the TV plunger all the way in at WOT, with the pan removed.
I understand the cable adjustment procedure, at WOT the TV plunger should be all the way in, the big question is where should the plunger be at idle speed.
There is an online consensus that the stroke of the TV cable should be 1.250. If I adjust my bracket for a stroke of 1.250 ( Distance between center of throttle shaft and center of pin for cable 1.110 ) and make the WOT adjustment I get these way to early up shifts. Testing with a gauge at idle speed I need to pull the inner cable an extra of 1/8 inch out to see any rise of line pressure. Thats the reason for my post.
Today I readjusted my bracket so at idle speed I have 2-3 psi more line pressure than if cable is removed and still can do this "automatic" WOT adjustment so the plunger is all the way in at WOT, this leaves me with a stroke of the cable between idle speed and WOT of 1.100 not even close to spec? but at least the transmission will not suffer from low pressure when testing.
Bad weather today, hope I can test tomorrow. I will let you know how it works out.
By the way I have changed the original Z28 governor to a Sonnax731, it had no affect on my shift issue. With the RV cam in the engine it will never rev past 5000 rpm.

 

This is what it looks like.

 

To me as i like it, Should be just touching or just very slightly compressing the Plunger . You dont want it looser as if they put the 10mm I call it a safty ball in it Then you would get really harsh coast downshifts or drop out of 4h every time you release throttle crusing . So at least touching or a tiny bit more is ideal at idle . with max out by wot .

 

Had a chance to test the car today. With this new adjustment of my tv cable geometry resulting in a rather short travel of the TV cable ( 1.110 ) my car really drove the way I want it to: At low speed early but notable shifts, pressing the accelerator further down, shifts comes later and more firm, have not tried WOT shifts yet. The way you prefer ( Frank ) would never work in my car. The transmission would believe I was at idle speed the first 1/4 of the accelerator travel and would shift to early and soft. Maybe that is because of the way my motor is put together with a very short duration cam, a lot of torque at very low rpm. Driving around town I just depress the accelerator very slightly.
I can not be the first person with these problems, there must be a reason Sonnax is selling this AS1-01K TV Cable Corrector kit:

The TV Cable Corrector kit, kind of solve the same problem I had, maybe just without the 25 hours I have spent fine tuning my TV cable geometry.

As stated, I really like the way my transmission is shifting now when in DRIVE, BUT maybe I still have an issue when driving around town at low speed in OVERDRIVE. Is it normal for these transmission to stack shift 3-4 at very low speed just above idle?

 

Interesting the way I do it the plunger would would start compressing the second the throttle moved as it would have no choice with the photo of your set up and the internal arm allready aganst the plunger. I can see how in the sonnax photo it wouldnt however. But In any case good you have found a workable solution.. As I always say Many solutions can exist for the same problem and whichever is best comes down to what works for you.