Changing up too soon.

[998automan]

Hi, does anyone know if it is possible to alter when gear changes occur? I find that mine changes up too early from 2nd to 3rd & 3rd to 4th so it gets `bogged down` and I have to override manually or use kick down. Not a major problem but would be a nicer drive if the gear changes were longer. Thanks.

[Stu]

Not really any changes you can make to the gearbox, however you can obtain delay to drive up-change with throttle control (not kick-down).

The photos below are taken from the owners handbook and explains how you can manipulate gear changes depending on throttle position.





It's just a case of practicing with the throttle position, but if you're a little more 'throttle happy' and can get the sweet spot you should get better changes, although this needs to be balanced with not revving the pants off it. Sorry if you already knew about this, but thought it was worth posting up if it might help a bit.

[jockduck]

Hi, not much to add, yes changing up on light throttle does happen early, I find Otto changes up to 4th about 18mph and when cold and on a slight incline "bogs down" a bit, I usually select 3rd manually to prevent the upshift and "rev' to the top of the hill and then select "D" helps prevent the flare 3-4 when cold too, when warm its no problem it climbes the hill well in 4th . If I used the throttle to maintain 3rd the car would accelerate over the speed limit. Don't worry my modern Chrysler with its electronic autobox gets things wrong too, I use the throttle often to get the gear I want.
Jock

[998automan]

Thanks Guys. Yes have experimented a bit with manual selection but not throttle control so much. Often just get kick down so will have a practice this weekend!

[Stu]

Damn good excuse to get some Mini driving in too  not that we need one!

[niceboy1275]

My matic was doing this when i first got it. I just adjusted the kick down cable so it was shorter and then it held the current gear longer before changing up.

[998automan]

Interesting. Mine doesn`t have a cable but a threaded rod, is this what you meant? Can you tell me how much did you adjusted it by and which way (did the rod get longer or shorter)? Does anyone else know about this? Thanks for your help.

[kalkat]

Shortening the rod is the way ........

[998automan]

Hi, have just found this article on the `Austin America` website:


I have done one driveability adjustment and it has made a huge difference in acceleration power. I noted when reading the AP Automatic Factory Service Manual that the shift point specification given for 3rd to 4th under full throttle was 56mph with a window of 4mph in either direction. So basically, 52mph-60mph at full throttle. This transmission was actually shifting out of 3rd and into 4th at about 47mph. That early shift was really keeping the engine from winding up and making some good torque and horsepower, especially when merging onto the freeway at speed.



The AP book states that the kick down rod, which runs from the carburetor linkage down to the bell-crank on the back of the transmission, can adjusted "shorter" (in other words, screwing it into the plastic heim joint connector at the bellcrank) to raise the shift point speed. I loosened the little locknut and turned the kick down rod inward 5 turns and this raised the shift point to about 53 mph. I left it like that and what a fantastic gain in the power produced under full throttle.



The engine pulls much harder through all the gears because their shift points are also raised. This effectively keeps the engine up in it's power band and by the time it shifts into 4th, it's really pulling nicely. An easy and very rewarding little bit of tuning.


Haven`t tried it yet so can`t say if it works or not! Interesting though....

[Stu]

Sounds like it will. I've made a mental note of this now too

[niceboy1275]

Sorry, I wrote cable instead of kick down ROD. sorry, but yes, glad you worked it out and shes humming along nicely now

[998automan]

Thanks. Have also found a really good article on the AP box on `austinmemories` web site which also includes loads of other interesting stuff, worth a look!  

[jockduck]

Hi, adjusting the rod helps but its not the complete answer, I tried changes including putting more thread on the rod for more adjustment but found if you go too far it prevents the throttle from being fully opened. The governor system is nice and simple but ultimately unsophisticated.
Jock

[998automan]

Thanks Jock will bear that in mind. How far is too far? (more than five turns). 

[jockduck]

You will find out! can't remember how many turns I even gave the rod some more bend to shorten it, after adjustment try opening the throttle full see if it still hit the WOT stop on the carb.
Jock

[998automan]

Thanks will do. I have since been experimenting with throttle position and it does make a big difference. So much so I`m not sure if shortening the rod will be necessary, however I will probably not be able to resist playing around with it at some point - will keep you posted....!  

[mra-minis]

Aug 17, 2015 15:33:52 GMT 998automan said:

Hi, does anyone know if it is possible to alter when gear changes occur? I find that mine changes up too early from 2nd to 3rd & 3rd to 4th so it gets `bogged down` and I have to override manually or use kick down. Not a major problem but would be a nicer drive if the gear changes were longer. Thanks.

Yes it is possible, for instance if you want to fit a racier camshaft etc....

[mra-minis]

Ok there is a little hocus pocus going on here... adjusting the governor control rod to be in it's correct position will give you the correct upchange points.

If however you play around with this point on an SPi auto you will end up with tears and no money... on an SPi it MUST be set correctly otherwise it will damage the engine.