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enigma
26-11-2004, 09:28 AM
I have had a change of heart with gearbox selection for VX. Basically I now want 2 Auto boxes.

WHY? I hear you shout! Well manuals require clutches and these tend to be very expensive, also zentac fried one in short time, Zedy1 says his brand new one is slipping on only slightly increased power. Also fabricating a mechanism to ensure both boxes change using 1 clutch and 1 gear lever will be tricky (not impossible though!). As for selecting 1st with one engine/gearbox and R for the other would be a total nightmare.

So I have done some research and the answer is 2 INVECSII AUTOS. :D But hat about all that nasty wiring? Well it can all be ditched! Basically the ECU controls when and where to shift based on all sorts of inputs including lever demand in tip mode. Well in a racecar with a competent person at the helm you dont need some fancy box of electronics to decide if you really meant to change gear when you said you wanted to, you just want it to do it! Also full AUTO mode is not required so all that fuzzl logic learn your driving style crap can be junked. All it does is switch power to 3 or 4 solenoids which determine which gear to select in the box. From my understanding once you know the pinouts of the solenoids its a simple matter of feeding them with a voltage in a particular sequence to go up and down the gears.

For a Toyota 4 speed the state of the solenoids is as follows (only 2 solenoids here)

1st gear, Solenoid 1 on, Solenoid 2 off
2nd gear, Solenoid 1 on, Solenoid 2 on
3rd gear, Solenoid 1 off, Solenoid 2 on
4th gear, Solenoid 1 off, Solenoid 2 off

Simple! £5 worth of electronics from Maplin will do this! :-b

All I need now is 2 AUTO boxes! Well I have sourced one :lipsrseal but it is a 4WD unit so once I have my hands on it I will investigat the possibility of making it 2WD. Shouldn't be too hard its just a case of mating a driveshaft the the point where the transfer box take off is. If all else fails a couple of transfer boxes will be needed and the rearward locked off. Obviously 2WD ones would be more suited, but I am concerned about power handling! I know of at least 2 4WD gearboxes that have held 450BHP! Thats 900BHP potential, or 10second 1/4 miles first time out........

So whaddya think? Mad or just barking?

Nick Mann
26-11-2004, 02:56 PM
Mad as always! But sounds like a solid enough idea to me. I guess 2WD autos will mostly be 4 speed, though? They would need the same ratios, as changing sequentially at different times would be a nightmare. How muh weight does the eletronics add? Full D would solve the problem of slightly different ratios....?

enigma
26-11-2004, 03:14 PM
Its not a question of weight, but complication, expense and availability!

zentac
27-11-2004, 01:19 PM
I will see what I can get for you......

zentac
27-11-2004, 03:54 PM
These guys have apparently got 2 in http://hills.blue-sock.com/aboutus2.php

enigma
29-11-2004, 10:51 AM
Hills only have one in, a 4 speed and want £500 for it :rolleyes5

Why cant someone sell me 2 (including torque converters) for £400?!!! :D

zentac
02-12-2004, 09:33 PM
Right, Ive found 2 x 4speed Tip boxes that we can get for £180 each if your interested DBA let me know.

Polabear
03-12-2004, 10:18 AM
Richard you am De Man..... :thumbsup: :thumb1:

zentac
03-12-2004, 11:43 AM
Just got good contacts where FTO`s are concerned :)