When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I plan on changing the throttle shaft on my quadrajet to get the correct geometry for a 2004r TVcable. I have a CCC quadrajet 17086008 that I removed from an Olds A5 intake that I bought years ago at a swap meet. I don't know what vehicle the engine came out of. I assume it was a 307. The carb number indicates it is a 1986 Chevy carb but it has a "straight out" fuel inlet. The lug placement for the cable on the throttle shaft of the "Chevy" carb looks identical to the lug placement on several late 70s Olds carbs I have that I am sure were hooked up to TH 350 trannys. My question is it possible the 1986 carb was hooked up to a TH350 transmission instead of a 2004r or 700r4?
Hope this question makes sense. Can anybody please post a pic of their 307/ quadrajet /2004r hookup?
Thanks, Ron
Last edited by rcwjr; November 26th, 2016 at 12:36 PM.
Reason: add a request
Thanks for the replies. Good information to know. I have a 1977 Olds Quadrajet carb on the car now, hooked up to a TH 350. I just needed confirmation that the linkage on it is the correct geometry for the 2004r because I don't want to burn the tranny up. I see no difference between the 1986 Olds Quadrajet CCC carb linkage and the 1977 and 1978 Olds Quadrajet carb linkages I have. Will post a pic when I get home in a few days.
Pics of carburetors. The throttle shafts look identical between the 1977, 1978 and 1986 carbs. Just want to confirm with those who know that the '77 & '78 carbs throttle shafts have the correct geometry for a 200-4R TV cable. sorry the pics are so big, first time posting pics. Thanks, Ron
Carb on left is 17057250, carb on right is17086008
Carb on left is 17058253, carb on right is 17086008
Yup, either will work. I forget off-hand, but some searching will tell you the center to center distance for throttle shaft to TV point. The earlier TH350 kickdown throttle brackets used on Chevy's have a different distance but look very similar.
I'm not sure what you're swapping the shaft *into*, but if it's the earlier 4M/4MC/4MV carbs, note that the shafts are different. So the bracket has to be cut off of each shaft and the later bracket affixed to the earlier shaft to fit an earlier carb. I had Sparky do that conversion a few years ago.
There was a post - either here or ROP - from a guy that made an adapter that attached to the 4M/4MC/4MV Olds throttle bracket and provided a TV point. Basically the same thing the EZ-TV guys do, but actually works on the Olds bracket. Very simple and effective.
Thanks for the replies. Again, real good info. Guess I don't need
to swap shafts.
I am going to have one of the late 70's Olds carbs
rebuilt then. Going on a 455 and a built 200-4r in my
64 Vista. Just going to be a fun driver.
everyday-performance.com has the TV arm conversion kit.
Kinda pricey but am sure it works.
Last edited by rcwjr; December 5th, 2016 at 06:28 PM.
Yup, that's the guy. Expensive for a sliver of metal, but the R&D and low production run, plus the cost and complexity of alternatives makes it a decent deal.
The later carbs (non-electronic) can be tuned to run really well, and arguably are easier to modify for APT.
Any updates on this? I've read just as many guys doing the throttle shaft swap as simply reusing their late-70's Quadrajet. There must be a reason for doing the swap, is the variation so minute it isn't obvious, and is it enough to matter for TV setup? I have both here but need to know more before deciding what to do.
Here's a little pic that shows the correct TV cable geometry. I used my computer to "blow-up" the pic to print as full-scale. I then used the print-out to compare to the throttle shaft on my EFI throttle body to check the geometry. The factory Q-jets measured 5" from the TV mounting bracket to the cable end (where it clips to the carb linkage).
I've also attached a copy of the TCI instructions for setting up the correct geometry. Hope this helps!
As long there is gradual pull and full pull at full throttle, it should be close enough. I found out that my Dualjet and Qjet 2004R bracket are not right with the factory cable adjusted. Not enough pull, I added 3 zip ties, I would rather have too much line pressure than not enough.
The distance from the bracket to the arm only matters if using an OEM non-adjustable (or severely limited adjustment) cable.
The critical dimension is the distance of the mount point from the pivot point on the throttle arm - that defines how far the cable will pull. The precise angle when the throttle is closed has a minor impact on that.
As long as you're using an adjustable cable such that full throttle == full cable extension, and the pivot length is very, very close, then you're OK. The earlier carbs had a kickdown connection which is similar, but not close enough really.
If there's not enough pull (mount too close to pivot) then you have to jack up the line pressure at idle. That'll make low speed shifts pretty annoying. If there's too much pull (mount too far) then the idle line pressure is **too low** which is what causes 2004r's to die. They need a minimum line pressure increase immediately when the throttle starts moving or they'll eat themselves to bits quickly.
Cliff Ruggles actually prefers the later carbs. I stuck with an earlier carb because it's what I knew and what I had parts for.
With a stock valve body, only the 1/2 shift is noticeable with my TV cable on the right side. Now add in bigger boost valves or modify the big weight on the governor and the part throttle shifts become much harder.
Thanks Guys. I'll keep it as is for the moment, car not even on the road yet, I'll let the big guys check and see if it needs something when the time comes.
I have a friend who had Cliff R modify his 403 carb to use the 307 OD shaft, hence thinking it must be very subtle but important. I have both here.
And thanks for scans CDRod.
Last edited by Aus78Formula; June 3rd, 2018 at 09:04 PM.
November 26th, 2016, 12:10 PM
