Famous94 Posted June 5, 2021 Share Posted June 5, 2021 So this last weekend I decided to update the engine on the Monte a lil. It was running fine before I decided to do any of anything but wanted to upgrade the intake manifold and carburetor. I got it all finished and it starts up great and idles great but noticed there’s a lot of slack in the throttle cable but it does open the carb all the way upon WOT but it feels like it’s not shifting right anymore. If I ease into the gas it shifts just fine but as soon as I give it middle to WOT it revs up but feels like it’s not wanting to shift till I let off the gas. I’m not sure if this is throttle cable related or the kick down. I know this isn’t the transmission itself cause I had it rebuilt less than 10,000 miles ago and it was shifting great before I put the new carb and intake on. I’d rather not take it to a mechanic for something that could be simple. I’m a bit new to the carbureted way of life and am wondering if anyone else had an issue similar and how they fixed it. It’s probably something simple but carburetors have never been my friend. Any advice would be greatly appreciated. Here’s a few pics of the carburetor currently. I pulled the throttle cable a lil so you can see the slack I am dealing with. Quote Link to comment Share on other sites More sharing options...
Dtret Posted June 5, 2021 Share Posted June 5, 2021 Did you try and readjust your kick down cable. It looks tight by the pic Quote Link to comment Share on other sites More sharing options...
70MC402 Posted June 5, 2021 Share Posted June 5, 2021 Having somewhat limited experience working on carburetors take my comments with a grain of salt, that being said i would think it would make sense to sort out the throttle cable slack before going after the kickdown issue. Th350 or 700r4? The kickdown cable length setting is dictated my the throttle position on the carb linkage, so adjusting the pedal to be better connected to the linkage should be the first priority. Once the throttle cable length is corrected and you dont have slack check to see when the kickdown is accomplished. Quote Link to comment Share on other sites More sharing options...
Famous94 Posted June 5, 2021 Author Share Posted June 5, 2021 I haven’t tried to readjust the kick down cable. I just looked and noticed a clip that I can pry with a screwdriver to loosen it. I’ve never had to adjust this cable is there a specific way to do this before I loosen the clip? Quote Link to comment Share on other sites More sharing options...
Famous94 Posted June 5, 2021 Author Share Posted June 5, 2021 70MC402 It’s a TH350 transmission. This is really my first time messing with the cables on a carburetor. The throttle cable doesn’t have a clip to adjust it. Do I need a different bracket to sort out the slack in it? Quote Link to comment Share on other sites More sharing options...
70MC402 Posted June 5, 2021 Share Posted June 5, 2021 Since i do more work on current era vehicles, I work at a dealer, my knowledge on the transmission kickdown is limited. As far as the throttle cable Lokar and a few other companies make universal cables that you cut to length. Thats an option. Another if youre good with metal fabrication is to make a bracket that comes off the carb thats further from the carburetor. Once the throttle cable length is sorted and you have good throttle action you should be able to press the "clip" in, and adjust the cable. Seeing that you have no shift i believe lengthening the cable would adjust your kickdown the right way. Hopefully some of the more seasoned members can chime in with experience. Quote Link to comment Share on other sites More sharing options...
cbolt Posted June 5, 2021 Share Posted June 5, 2021 Looks like you may in fact need a different bracket. When I installed my carb I had to change the stock bracket out for one that worked better, but since that was years ago I do not recall exactly what bracket I went with or where I got it. Quote Link to comment Share on other sites More sharing options...
wallaby Posted June 5, 2021 Share Posted June 5, 2021 There is usually some fine-tuning of linkage when doing a carb swap. The new carbs are sort of "universal" and may not be exactly the way you are used to. I am putting together a small block right now with that same carb, and the relation of the throttle to the kickdown is a bit different than GM carbs had. It would seem that the linkage attachment points on the new carb are a bit closer together than on the original carb...(more compact, if you will)...and it messes with the cable travel on both the throttle and the kickdown. You can start by loosening the bolt on the back of the carb that also holds down the throttle cable bracket, and doing your best to rotate that bracket as far rearward as it will go to eliminate some of the cable slack. I had to modify my bracket a bit to get a good fit, so maybe a new bracket would be better to experiment with...rather than messing with the bracket you have? I also made myself a bushing that goes in the large hole where you presently have your return spring, so I can mount my cable connection there. A washer or 2 of the correct outer diameter might fill that hole like a thin bushing. With a larger washer on both sides to sandwich the bushing in place, you can mount your throttle connection pin through it all to hold the whole mess together.. So the idea is to move the cable connection point forward, and the cable housing mount rearward. Once you have that set up to your liking, the trans kickdown can be hooked up and adjusted. My setup was good, but it didn't pull the kickdown cable far enough. The plastic clip used for cable adjustment has plenty of travel to make the cable longer, but limited travel for making it shorter. I had to enlarge the holes in the bracket that bolts to the rear of the intake so I could move that bracket a bit further rearward to make my cable a bit shorter. Adjustment of the kickdown is simple...Lift the plastic clip on your cable adjustment. Open the choke on your carb with your finger, and with the other hand open the throttle fully. While holding the throttle fully open, push the cable plastic clip back down to lock it in place. (it will snap when it seats fully) The cable adjustment should be correct then. There should be a tiny gap between the pin on the carb and the end of the long slot on the cable end....you want to achieve full throttle just before the cable reaches full extension, but you also want the cable to be pulled as far as possible without hindering the carb movement. 2 Quote Link to comment Share on other sites More sharing options...
Famous94 Posted June 5, 2021 Author Share Posted June 5, 2021 Wallaby thank you for the insight and detailed instructions! I’m going to give it a try and see how it works. I figured it had something to do with my cables but wasn’t completely sure. I got my fingers crossed that this will be the fix that gets her back on the road breaking necks of everyone that drives by! Thank you everyone else who commented and gave me their 2 cents on the problem I’m having. I now feel more confident that the cables have been my problem with getting the car to shift correctly while driving. Quote Link to comment Share on other sites More sharing options...
TheBMan Posted June 27, 2021 Share Posted June 27, 2021 I agree with @wallaby. The ratio for the movement and spacing of the cables is going to be different now. Edelbrock makes replacement brackets that are adjustable. Might want to take a peek at those. https://www.edelbrock.com/shop/accessories.html?cat=394 Quote Link to comment Share on other sites More sharing options...
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