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**HO455** · 05-25-2020, 10:08 PM

Went out Overdriving today! There were a few hiccups. I've never had a vehicle with a TH350 before and I wasn't aware of the whole kick down cable adjustment thing. I had to remove the bracket on the manifold and pull the cable as far out on the passenger side of the engine compartment to get a good look at the cable before I figured out that you have to lift the tab, then floor the accelerator, then push the tab back down to get it to set to the right length. Kind of like a 700r4 TV cable. Needless to say before I did all that my first test drive was quite short and never got out of 1st gear.

I also had to readjust the new brake light switch. I set it to the same distance the old one was at, but in that position only the brake light contacts had continuity the 2nd set for the lock up were still open. It took 20 minutes with a voltmeter to fix that little detail. And the last item to correct was that I had overfilled the transmission by 3/4 of a quart. Fortunately I had my MityVac and it was easy enough to remove the extra fluid.

Once on the road the GV shifts into overdrive at just above 40 mph. It shifts into overdrive quite firmly although it may feel harder as it appears that the converter is locking up before the GV shifts up. There is a hook up on the GV controller that will unlock the converter momentarily as the GV shifts. I may look into using that function since it's there and would only require me to add 5 or so feet to the existing ground wire on the lock up circuit

I need to rig a way to hook up my hand held tachometer to be able to get some accurate RPMs to post. The factory tachometer in the dash reads approximately 7-900 RPMs high. So for now with about 20 miles of testing the RPM at 55 mph is about 2000. The old TH400 was turning about 2700 at 55 mph. The lock up drops the RPM at 45 mph about 200 RPM.
I didn't do much messing around with the manual shifting. I just left it in auto and paid attention to all the noises with my fingers crossed I didn't hear a bad one.

It will take some time to adjust as I noticed myself driving faster. The truck is definitely quieter with the lower RPMs and I apparently keep my speed by listening to the truck.

More to follow.

05-25-2020, 10:08 PM	#650
HO455 Post Whore Join Date: Feb 2016 Location: Portland Oregon Posts: 10,833	Re: Working Man's Burbon Went out Overdriving today! There were a few hiccups. I've never had a vehicle with a TH350 before and I wasn't aware of the whole kick down cable adjustment thing. I had to remove the bracket on the manifold and pull the cable as far out on the passenger side of the engine compartment to get a good look at the cable before I figured out that you have to lift the tab, then floor the accelerator, then push the tab back down to get it to set to the right length. Kind of like a 700r4 TV cable. Needless to say before I did all that my first test drive was quite short and never got out of 1st gear. I also had to readjust the new brake light switch. I set it to the same distance the old one was at, but in that position only the brake light contacts had continuity the 2nd set for the lock up were still open. It took 20 minutes with a voltmeter to fix that little detail. And the last item to correct was that I had overfilled the transmission by 3/4 of a quart. Fortunately I had my MityVac and it was easy enough to remove the extra fluid. Once on the road the GV shifts into overdrive at just above 40 mph. It shifts into overdrive quite firmly although it may feel harder as it appears that the converter is locking up before the GV shifts up. There is a hook up on the GV controller that will unlock the converter momentarily as the GV shifts. I may look into using that function since it's there and would only require me to add 5 or so feet to the existing ground wire on the lock up circuit I need to rig a way to hook up my hand held tachometer to be able to get some accurate RPMs to post. The factory tachometer in the dash reads approximately 7-900 RPMs high. So for now with about 20 miles of testing the RPM at 55 mph is about 2000. The old TH400 was turning about 2700 at 55 mph. The lock up drops the RPM at 45 mph about 200 RPM. I didn't do much messing around with the manual shifting. I just left it in auto and paid attention to all the noises with my fingers crossed I didn't hear a bad one. It will take some time to adjust as I noticed myself driving faster. The truck is definitely quieter with the lower RPMs and I apparently keep my speed by listening to the truck. More to follow. __________________ Thanks to Bob and Jeanie and everyone else at Superior Performance for all their great help. RIP Bob Parks. 1967 Burban the WMB,1991 S(stink)-10 Blazer,1969 GTO, 1970 Javelin, 1952 F2 Ford 4X4, 29 Model A, 72 Firebird. 85 Alfa Romeo If it breaks I didn't want it in the first place The WMB repair thread http://67-72chevytrucks.com/vboard/s...d.php?t=698377 Last edited by HO455; 05-25-2020 at 10:19 PM.