Auto tips/tricks/mods?

[nedge2k]

Is there anything that can be done to the auto box?

Forgot how annoying they were to drive. Not changing down on decel until you start to accel again, holding and not holding in gear when you want etc.

Is there anyway to force an upshift when in drive?

For instance say I want to accel pretty hard but not have it screaming to the redline all the time.

Similarly, is there a way to hold it in 3rd/OD?

Say when you want to accel without dropping down a gear and you haven't hit the kickdown switch.

[nedge2k]

Not being very knowledgeable on auto boxes, did a bit of reading and there are a few things that can be done...

The auto box *should* be a Jetco 4N71 variant, the L4N71B.

First and easiest thing is to modify the throttle vacuum valve's rod. According to this article, a mod like this can alter shift patterns.

Second thing to do is install a "shift kit" into the valve body (gearbox's hydraulic "ECU"). This gives faster but slightly harder shifts and supposedly allow gearbox to cope with higher powered engines due to increased oil pressure. http://www.viczcar.com/forum/index.php?topic=6869.0

Third thing is to convert the valve body to "full manual", allowing you to shift as a clutchless manual. Americans like to do it for racing! This would change the gear selector from PRND21 to PRN123. There's supposedly a way to make it semi-auto to but have not found much on either with regard to the S12 box.

[thenomisf]

Just to bring back up an old thread, I am going to manual my auto soon, but I would be interesting in having some (potentially destructive) fun with it first, so I might have a play around with it/valve body and see what I can do!

[northerner]

The only one who will know is Silviagod as he drives auto's. They dont like the boost turned up as they slip

[nedge2k]

Well that I can confirm!

...although with mine, it's more the torque converter slipping in O/D during lockup. Makes it a right pain to overtake on the motorway.