John in RI

iTrader: (167)

I'm about to load an SBC into an 86 Z28 and need to identify / find the proper 700R4 Throttle Valve cable ( kickdown or detent cable to some folks.) I've searched and read too many posts then I should have and never really found the answers I was looking for. I'm posting this to relay what I know and to find out what I need to know.

I need to find a CARB TV cable for a 700R4.

check out this pic: The circled area shows that the transmission end of the cable is pulled inside the housing. This is how all the cables were pulled when I took measurements. (Please keep in mind that the cables are not perfectly straight and your measurement might be 'off' compared to mine a 1/16th or so.)



Here is a picture showing several different TV cables. I have previously Identified all these cables with the exception of 1 of them. ( I think the unidentified cable at the top might be the carb version !?!)



Top-to-bottom they are :

A: Cable end = 6" = UNKNOWN, V8? Carb?
B: Cable end = 5 3/4" = Crossfire
C: Cable end = 7 3/4" = TBI
D: Cable end = 6 1/2" = TPI
E: Cable end = 5" = V6 ( MPFI ? )

That simple comparison makes it hard for me to believe that a carb and a TBI cable are compatible parts - something I've read over and over again in previous posts. Take a look at this pic: This is where I placed the tape measure and measured each cable to the tip to get the measurements above.



Take a look at this pic: This is where I began the measurements for the overall cable length. (I pulled the cable as tight as possible for the most accurate readings possible....)



This is where I ended the measurement at the other end of the cable:




A: Overall = 37", Cable end = 6" = UNKNOWN, V8? Carb?
B: Overall = 31 3/4", Cable end = 5 3/4" = Crossfire
C: Overall = 35 1/8", Cable end = 7 3/4" = TBI
D: Overall = 43 3/4", Cable end = 6 1/2" = TPI
E: Overall = 39 3/4", Cable end = 5" = V6 ( MPFI ? )


Does anyone have access to a KNOWN carb V8 TV cable that could provide some measurements ?? I'd REALLY prefer to install the proper cable before the engine/tranny get lowered into the engine bay. The only other TV Cable I'm not sure about yet would be a V6 Carb TV cable.......

sofakingdom

iTrader: (1)

While I don't know for sure that it would make any difference, I suspect that this is NOT an accurate way to measure these.

In particular, it doesn't look to me like all of those are "adjusted" the same. Specifically, the ones that look "longer" also look like the outer is slid further up into the adjuster.

I'd suggest instead, setting the "adjustment" for all the cables the same, preferably all the way out (making the outer fully long); then measuring the length of the OUTER from the seating surface at the trans to the seating surface at the throttle, and measuring the INNER from the center of the trans link hook to the center of the throttle clip.

We do in fact know that the overall length of the OUTER is different between TPI and carb or TBI, due to the throttle body location being much farther forward. Your method fails to capture that critical fact.

You might find CONSIDERABLY fewer variations if you did it that way; as well as capturing more of whatever REAL variations actually exist. (or maybe not...)

Pat Hall

iTrader: (31)

Yeah, I was kinda thinking the same thing that Sofa said about how to measure them. The reason just about everyone says to use the TBI cable on a carbed car is they're really easy to come by and the TBI unit is pretty much located in the exact same position on the intake manifold as a carburetor. As long as it's adjusted correctly, I can't see why the TBI cable wouldn't work.

John in RI

iTrader: (167)

Thanks for the suggestions....... Because you "don't suspect" and because to you it "doesn't look" means nothing. I'm looking for answers - not criticism. I've got no problem being wrong - but don't just sit at your keyboard and criticize my methods without at least checking first, or even understanding the information your critcizing.

Seems like maybe you didn't get enough sleep last night:

A: Overall = 37", Cable end = 6" = UNKNOWN, V8? Carb?
B: Overall = 31 3/4", Cable end = 5 3/4" = Crossfire
C: Overall = 35 1/8", Cable end = 7 3/4" = TBI
D: Overall = 43 3/4", Cable end = 6 1/2" = TPI
E: Overall = 39 3/4", Cable end = 5" = V6 ( MPFI ? )

I completely expected this type of a response; ( seems to happen a lot here. ) It's why the title asks for "Just the facts please". Besides pulling them tight I also ran a string following the contours of each cable. The overall measurements of the cables are very close' close enough so that 1 cable can't be mistaken for the wrong type. To clear things up for you; that measurement was for the OVERALL LEGTH of the cables,..... not the internal cable itself. You would find the measurements accurate if you took a second to help/check rather than just posting what you think.

All TV cables pictures are @ ZERO adjustment. How that could lead to inaccurate measurements is something you will need to explain in detail. I don't know what variances your talking about; the lengths are different becasue the cables are for different applications. Pulling the sheath fully extended could lead to invalid measurements IF there is an difference in the sheath itself. I don't know that - and don't care. My measurements do not allow such a *variation * because the sheath is not part of the measurement. My beginning and ending measurements start and stop at a fixed point that is the same on all cables; about as close as I could get to a standardized measurement on all the different cables and makes it easy for anyone else in the world willing to check the measurement against thier KNOWN carb cable.

When both of those cable are compared ( CARB cable is NOT positively Identified yet !) the end of the cable sticking out of the carb housing is 6" and 7 3/4" for TBI. If I pulled the sheath from the housing on both units,....this difference does not disappear. 1 3/4" is a very significant difference in cable length. Just because the length of the overall cable is the almost the same doesn't mean that the internal cable length is the same. ( as I just proved ) Once mounted and set to ZERO adjustment the TBI cable will be 1 3/4" longer than the carb(?) cable at the Carbs throttle linkage.

I could make a fishing line work if adjusted properly, but that's not what I'm after. It's quite probable that the TBI cable could be adjusted to work on a carb...... but I'm hoping to find someone willing to take 2 minutes to verify the measurments on a KNOWN CARB TV CABLE so I can verify that I am using the correct cable - not trying to make a cable for another application work on a carb set-up. It will be easy to replicate my measurements due to the Zero adjustment positioning of the sheath and because of the fixxed location of the beginning and ending points of the measurements.

Let me ask again to be sure that I'm asking this in a clear way.

Does anyone have access to a KNOWN carb V8 TV cable that could provide some measurements ??

P.S. info regarding a carb V6 cable may also help others in the future.

vetteoz

iTrader: (13)

FWIW
the V6 cable is noted as too long and the CFI as too short for a carb swap

https://www.thirdgen.org/forums/post...32-post24.html

https://www.thirdgen.org/forums/tran...-too-fast.html

John in RI

iTrader: (167)

Thanx for the link,......

I had read that thread and there's a LOT of invalid information in there. In fact; if you read thru it again you'll see that he never tried a V6 TV cable on his carb V8; someone else got confused.......

At one point there was a statement made that the 37" cable was for an 83 TBI ( Crossfire ?). However, I KNOW the Crossfire cable is less than 32". Too bad - for me - that the overall length of the new cable he bought ( for an 86 TBI "H" code !?!) was never included in that thread.

I'm hoping the 37" cable IS the carb cable. it's the only one I've got in my possession that is not positively ID'd and it's the one I need to install sometime in the next couple days. Since it's the closest in overall length to the TBI cable the odds seem to be in my favor !

Keoman

iTrader: (3)

This may sound like a douchebag move, and it is, but order the correct one from the parts store, measure it, if you already have the correct one, return it and voila. No more guess work...
Seems all too simple.

The overall cable length doesn't matter as long as it reaches the tranny. What matters is the cable mount (right after the d-ring button) to the throttle linkage point. This is the adjusted distance that will tell the trans to shift.

read this
http://www.tvmadeez.com/article/index.php

Pat Hall

iTrader: (31)

John I agree, while you're not 100% positive the 37" cable is for V8 carb, all factors seem to point that way. Being that close to the length of a TBI cable, more than likely it's the one you're after.

John in RI

iTrader: (167)

Well; I rolled the dice and used the 37" cable when I dropped the drivetrain back in. I got lucky and unlucky: the first tranny I installed only had 1st and reverse ,..... But once the tranny was swapped out I set the TV cable and the replacment tranny is shifting great. I've got smooth part throttle shifts and a well timed downshift ! Time to put some miles on this baby !

joshc

iTrader: (1)

I just happen to have a brand new in box Gm TV cable for my 1986 Carbed Trans Am.
Got about 37 + 1/4
Cable end was just a hair short of 6 inches.
Gm part # 25515598

John in RI

iTrader: (167)

Re: TV Cable Kickdown Detent --> Just the facts please




AWESOME Update !

gta_knight

Kicking up an old thread after a search ! Lol

I'm trying to order a new TV cable for my 84 Trans Am. You go on rockauto and select 5.0 V8 HO, which all had 700R4 transmissions ?

Then it presents me with 3 different length cables. Argh !!

So you say a 37" cable is the correct one for a carb setup and 700R4. I'm having the same problem as you did further up where I only have reverse and 1st. I've ordered a new governor rebuild kit incase it's that first

skinny z

An old thread but timely.
I've questioned which cable I have since I cobbled my heap together a few years back.
I'm certain I don't have any one of the cables John has listed. With 6 1/4" x 35 3/4" it doesn't match with anything on the list.


That said, I've been using it on a Holley carbed (with corrector) application and also have an adjustable TV cable mount. My thinking it's the exposed end of the cable that is the critical value while the cable jacket itself is for the specific application (as in distance) the cable has to cover.
Now with the about to be new transmission going in, I may revisit this and order the correct GM part. PN 25515598 as posted.

gta_knight

the lengths I'm getting on rock autos site are

44.74"

44"

48"

But I don't know where they get that measurement from. Ffs !

skinny z

It would seem that the first two in Rock Auto's list are essentially the same at 44" (+/-).
The third is adjustable. I suppose at 48" the extra length is to allow one to suit multiple applications.



For what it's worth it doesn't really matter which cable is used provided that the correct geometry is maintained. However in a stock setting like yours, there is no capacity to "tune" the geometry, vis a vis, an adjustable TV cable mount, so you're restricted in your choices. The adjustable cable (third on the Rock Site list) might serve your needs if you're search turns up nothing else. You can confirm it's correct operation by measuring the geometry as you make adjustments.
All of that said, the GM PN posted looks to be an exact fit given joshc's post earlier.

EDIT: Searching GM PN 25515598 at Rock Auto brings up the three cables in question. That bit of information more or less confirms that Rock Auto cable is the going to work wouldn't you think?

skinny z

Conclusion?

KevinKnightNYC

I'm kind of in the same boat. I have two 82's that have had sbc 350 swaps, both are running identical Edelbrock carbs with no computer and both have rear drum brakes. There is a local guy with two GTA's sporting the 700R4 with posi disc rears that I want to install into the 82's.

Is there a concise list as to what I should take with the tranny, drive shaft, and rear end off the donor vehicles? Lastly I guess I could just buy the gm #25515598? I need to put a throttle position sensor on the carb for something else. Will this change anything?

skinny z

Where along the cable did you establish your length? Using the data you've supplied, I can guess it's at the 39 3/4" mark. (Maybe)
I have a new, just purchased from my local GM dealer, an ACDelco 25515598. Listed as a replacement TV cable for a carbed '84 Camaro.
I'd like to post the dimensions for the archives.

skinny z

For what it's worth here are a couple of pics of the ACDelco 25515598.
Not sure where it slots to the range of cables illustrated here.




From the carb anchor to the adjuster: 37-1/8".




Fully extended cable, carb anchor to jacket: 4-7/8"

P.S. Transmission with TV cable adjusted as per "the book", shifts wonderfully under any and all conditions. Line pressures are as per the ATSG specifications.