Shift Kits

[king_panther]

Hey all,

I swear I've seen this mentioned elsewheres, & Madhav's FS thread reminded me about it.

Has anyone actually fitted a shift kit to their autos?

What are they, & do they need to be suited to our gearboxes or is it a generic piece of gear that can be installed?

I'm also told that installing a shift kit on the RVR is also a must have item.

 

[steveP]

duno how relevant it is, but i got one on my silvia (stage 2 with a high stall converter). gear changes are ultra quick. and with the hi-stall, it feels like a clutch kick between gear changes, sorta sling shots the car. even tho its ideal for drag, its very streetable and excellent in the hills. however a little tricky to get used to at first, as it will change gear and break traction around a corner if ur not careful.

 

[king_panther]

I'm a little confused by the explanation on Wikipedia;

"An automatic transmission's main focus is smooth shifting between gears. To accomplish this it often goes into two gears at once while shifting up, which is known as a shift overlap. In these cars, it is a kit that can reduce or eliminate the shift overlap. It will also reduce wear because the transmission won't be trying to drive in two gears at once. Typically, adjusting the shift 'pattern' in an automatic gearbox involves interrupting the signal from the ECU to the transmission (usually with a switch, though the adjustment can be made permanent). The resultant shift pattern is usually very aggressive (it will 'bang in' to gear) thus making a car a handful in the wet as well as opening the possibility of damage to already weakened transmission internals. It is advised that you service your transmission more thoroughly than usual if you undertake this adjustment."

So..... it's meant to reduce wear on the transmission by reducing shift overlap, but can damage transmissions that are weak, & requires more frequent servicing?

I found these guys; http://www.shiftkits.com.au/ & they have systems for Ford & Holden. So do I need to source a kit that will be suitable for our cars?

 

[Scottie]

I believe you can change the size of the valves in the valve body. This will allow more air/fluid and result in quicker changes.

I would advise on doing anything tho, our boxes seem fairly touchy as it is, and yes, i have seen it covered on here before.

 

[Hotwire]

The "shiftkits" those guys sell is a couple of 50c resistors in a pretty plastic box...
They work on the principle of changing the voltage provided by the transmission ECU to the transmission. The ford and holden transmissions have variable valves in the boxes that will provide a certain line pressure depending on the voltage provided to the ECU. They use a simple voltage divider circuit from a couple of cheap resistors to provide a lower voltage to the valve which in turn increases pressure = shifts faster & harder.

This may or may not work for a VR4 depending on the electronics, but given the complexity of these boxes (especially compared to the good old ford BTR box) I'd say its certainly not that simple. The next step for a VR4 would be to change the valve bodies like Madhav has done, and this is a costly exercise.

 

[Hotwire]

Here is how the Ford kit is made:
http://www.fordforums.com.au/showthread.php?t=107689

In the ford BTR97LE transmission, S5 (solenoid 5) is the solenoid that controls line pressure for shifting gears, and that is the voltage they are varying. Looking at Kats pinout of the ECU, I can't see a simple solenoid for line pressure, so short of a full english transmission manual, don't hold your breath for a cheap electronics solution...

EDIT:
A quick google search found nothing on a shift kits for Magna's either so not looking like an easy solution

 

[smitty]

A mate's BF XR6 turbo had it's shifting vastly improved just by getting his ECU flashed and re-tuned.... they way it was explained to me, this was achieved through setting the ecu to tell the transmission "lies"

 

[king_panther]

I'm getting a shift kit put into my RVR after I get it back on the road.

TransGo in the USA make a kit for those 4-sp Mitsu autos.

But yea no idea about our boxes. Would be nice.

 

[unclepaulie]

afaik, trans shiter kits cant be used (as in there is none readily availble) on the vr4 auto boxes due to invecs system

i might be mislead tho

 

[Madhav]

afaik, trans shiter kits cant be used (as in there is none readily availble) on the vr4 auto boxes due to invecs system

i might be mislead tho

I have had one fitted to my one, the whole gearbox is for sale. It's basically a valve body upgrade. M V automatics in SA can do it easy.

 

[unclepaulie]

oops, i meant like a B&M shifter handle thing my bad,

i blame beer for that lol