Long story short, the guy at emissions messed with my carb and didn't pay attention to anything, so car wouldn't start. So I started tuning carb all over, with vacuum gauge. It was only 10psi vacuum, so I thought I would check timing and see if I could get better vacuum. The timing was way off, firing at TDC at idle. So I adjusted to 12' advance and then tuned carburator, and the vacuum went up to around 17psi. I adjusted carb and went on my way. But now it shifts funny. It stays in gears a lot longer than it used to and doesn't want to kick into higher gear at cruise speed. Then when I finally get it into high gear at say 55mph, then if I even touch the gas, push it in the slightest it kicks down a gear and revs up. So I heard something about a kickdown adjustment on the carb? I am thinking that this was adjusted to how the car was running at 10psi vacuum, and now it's off? And also was thinking my power valve inside carb may be off, if it was changed out or set for lower. Isn't it supposed to be 1/2 of the total vacuum, so on current it may be a 5, when now I need a 8?
been awhile since i've played with an automatic trans, but it sound as if the vacuum modulater my be going, or has gone out on the trans. Just a thought.
Make sure the modulator hose is connected! It may have been knocked off during the work. Also check the kickdown linkage for proper movement and return.
Ok, I will check both of these thanks guys. LOL, I am going to have to do some research before I know what either of these look like or where to find them...
The kickdown linkage connects to the throttle lever on the carb and the other end is connected to the transmission shifter linkage, but on a separate lever from the shifter linkage. The Vacuum modulator valve is on the passenger side rear of the transmission main case and has a vacuum hose connected to it and one of the rear intake runners, to receive full manifold vacuum. Just me, but it sounds to me like it's working perfectly. It should take longer to upshift and downshift quickly.
Thanks for info on locations. I assure you it is not shifting correctly. It is revving very high with minimal throttle input. Shifting from 2nd to 3rd is at like 60mph at 3000+ rpm, even when keeping throttle stable. Then when I barely touch it slams into 2nd and kicks up the carburator. At least I don't think it is right. It feels so much different and more harsh than any other vehicle that I have ever driven, including my previous maverick.
Upshifts should be firm, not soft. And for most, longer upshifts are preferable to short shifts, to allow the engine to rev into the upper end of the powernband before upshifting. Now the quick down shifts may be a problem, but from the sound of your description, the upshifts sound about right for a transmission with a shift kit in it.
Ya, you may be right. My previous maverick had a stock transmission and rear end. This one does not. Maybe I can adjust the upshift with the modulating valve to be a little lower RPM as daily driver, and higher when I go to the strip?
Yea, you should be able to adjust the shift point to a degree by adjusting the modulator valve. The too quick down shift should be adjusted via the throttle linkage
