Only 4500 RPMs
Thread Starter
Racer
Joined: Oct 2002
Posts: 449
Likes: 2
From: Fayetteville, PA
Only 4500 RPMs
Please someone help me, this is driving me crazy! When I accelerate from a stop my car shifts at 4500 rpm max. If I floor the gas at 50 mph (about 2500 rpm) I doesn’t downshift but just accelerate. I checked the kick down switch at the gas petal and it works. I changed the solenoid in the trany and that works.
My question, is there an adjustment that synchronizes the both or is that normal for anL82 with TH400 and 355 rear-end?
Thanks in advance for advise. :confused:
Le Mans Master
Joined: Aug 2000
Posts: 9,662
Likes: 7
From: Semper ubi, sub ubi
Cruise-In VI Veteran
Cruise-In VII Veteran
Re: Only 4500 RPMs (77BlueL82)
Shift points are controlled by the governor, which consists of springs and weights which open and close valves that shift the car. Here's a great link on how it all works, sort of long reading but great information.
http://yarchive.net/car/transmission.html
The shift point probably should be at more than 4500 rpms, probably right at your redline on the tach. I bet your car has had an transmission service or rebuild, when a shop does this it normally just replaces the governor springs and or weights with the stock stuff TH350 stuff, which probably shifts at 4500 for a family sedan or a pickup truck.
Shift points can be slightly changed by the vacuum modulator, if you have an adjustable modulator, there will be a screw inside the port that the vacuum line is attached to. For the life of me I can't remember which way you adjust it to raise or lower your shift points.
Good Luck!
[Modified by Smokehouse69, 9:47 PM 2/9/2004]
http://yarchive.net/car/transmission.html
The shift point probably should be at more than 4500 rpms, probably right at your redline on the tach. I bet your car has had an transmission service or rebuild, when a shop does this it normally just replaces the governor springs and or weights with the stock stuff TH350 stuff, which probably shifts at 4500 for a family sedan or a pickup truck.
Shift points can be slightly changed by the vacuum modulator, if you have an adjustable modulator, there will be a screw inside the port that the vacuum line is attached to. For the life of me I can't remember which way you adjust it to raise or lower your shift points.
Good Luck!
[Modified by Smokehouse69, 9:47 PM 2/9/2004]
Race Director
Joined: Oct 2000
Posts: 17,102
Likes: 7
From: Fair Oaks, OK
Re: Only 4500 RPMs (comp)
Isn't there also a problem with a piece of the accellerator linkage that gets bent and won't let you go to WOT? Maybe this is adding to the problem?
When floored, my car will shift at around 5,000 rpm. It will downshift into second from 50 mph, though.
When floored, my car will shift at around 5,000 rpm. It will downshift into second from 50 mph, though.
