Garage Whifbitz Supra Mk4 7 Speed DCT Gearbox Conversion

Description

We were the first company in the world to make a DCT 7 Speed gearbox conversion kit for the Supra JZA80 and now we’ve taken it a step further using the latest Getrag 7 Speed DCT gearbox as fitted to the BMW F8X M3/M4.

The DCT (dual clutch transmission) gearboxes have been steadily taking over from the manual gearboxes over the years, most of the supercar manufacturers use them in their cars these days, Ferrari, Lamborghini, Porsche, McLaren, etc all use DCT gearboxes. And are now being used in main stream cars too like Audi, BMW, VW, Renault, etc.

The benefits of the DCT’s are:

1. Super fast gearchanges, the 7 speed Getrag gearbox we are using changes gear in 80 milliseconds. This in turn massively reduces acceleration times improving the cars performance. The DCT version of the M3 is 0.2 seconds faster from 0-60 over the manual version, thats just one gearchange. Imagine if you’re on a race track,how much faster it would be on a lap.

2. Manual and auto modes. So if you want to just poodle around in auto mode it drives as smooth as a normal automatic. Then in manual mode you can use the flappy paddles on the steering wheel.

3. Throttle blipping on downshifts, this sounds amazing!

4. Better fuel economy and less power loss than any auto gearbox as its direct drive, no power sapping torque converter.

5. Launch control, this can’t be done on auto cars.

6. Clutches are immersed in fluid so don’t wear as fast as normal clutches.

The gearbox is attached to the engine with a custom made billet flywheel and billet aluminium adaptor plate. The conversion comes with a new mount for the gearbox which allows it to bolt onto the stock location and uses a new propshaft flange to bolt directly to a stock Supra auto propshaft too, (manual propshaft does not fit).

We’ve also fitted a drive by wire throttle using a Bosch item that’s normally found on a Porsche 996 turbo. This bolts directly to the stock manifold with a custom made billet aluminium adaptor. The throttle pedal has to be changed to a drive by wire type too, the pedal we use bolts directly into a Supra, all available as part of the kit.

We’ve also fitted carbon paddle shifts to the steering wheel so you never have to take your hands off the wheel to change gear, flick the right paddle to change up and the left one to change down.

So far in testing we’ve pushed the gearbox with stock clutches to 650 lb/ft torque, plenty for most people, it may take more but we haven’t tested beyond this yet.

We see this conversion as a major step forward bringing the Supra right up to date with latest technology transmission. For those with a tuned Supra running the autobox our DCT gearbox conversion will be a revelation, no more slush box with no control over the gearbox, no more waiting for upshifts and less power loss as there is no torque converter sapping it. You can cruise around in automatic mode just as you would with an autobox but then switch it into manual to change gear with the gear lever or flappy paddles.

Manual owners will enjoy this too, gone will be the slow clunky gear changes offered by the V160/1 gearbox. And don’t forget after the conversion you will have your 6 speed gearbox and conversion parts to sell and as you are probably aware they are worth a lot of money with prices on the up.

The transmission tunnel needs minimal work to clear the gearbox bell housing, small adjustments with a tapping tool!

The gear ratios of the 7 speed gearbox are:

1st – 4.806

2nd – 2.593

3rd – 1.701

4th – 1.277

5th – 1

6th – 0.844

7th – 0.671

Supra V160 6 speed gearbox ratios are;

1st – 3.827

2nd – 2.36

3rd – 1.685

4th – 1.312

5th – 1

6th – 0.793

So as you can see the 7 speed gearbox has very tightly stacked ratios and longer 7th gear compared to the 6th gear of the V160 for cruising. Be aware that the 6 speed cars use a 3.2 diff and the auto cars have a 3.7 ratio as standard so you might want to change the diff ratio if its an auto.

The car feels so fast with these new gearbox ratios, the difference is astonishing, rapid fire gear changes and faster response due to the gear ratios being stacked closer together.

The other thing we are keen to mention is we can make this work on pretty much any car, not just the Supra. The Supra conversion we’ve made is very similar to the Chaser and Aristo for instance. We can have adaptors made to suit any RWD car!

Our kits includes:

• Billet aluminium gearbox to engine adaptor plate to suit the BMW M3/M4 F80 gearbox
• Billet steel Flywheel and flywheel adaptor to attach to the gearbox with new genuine Toyota flywheel bolts and clutch cover bolts
• Billet steel propshaft adaptor to fit auto propshafts only, this will not fit a 6 speed propshaft as its longer
• Billet aluminium gearbox mount using oriignal BMW gearbox mount rubbers
• Mounting bolts/nuts to mount everything to your Supra

On top of this you will need:

• A control unit for the gearbox, Can TCU works really well
• A stand alone ecu to communicate with the Can TCU
• BMW 7 Speed Getrag gearbox from the F8x M3/M4, we’ve found these used for £600 upwards.
• BMW M3 E90 gear lever. 
• Steering wheel mounted flappy paddles if you want to control the gearshift from the steering wheel. Plus a steering wheel and boss kit if you are still running the standard steering wheel.
• Drive by wire throttle body adaptor and drive by wire throttle body, we use our own adaptor which allows the fitment of a Bosch DBW throttle. This bolts directly on to the standard Toyota Supra inlet manifold for easy fitment. 
• Drive by wire throttle pedal, we use a Toyota item which bolts straight in to replace the stock pedal. 
• Gearbox oil cooler using our adaptor to allow AN fittings to be used. 

Plus all of the above needs wiring from the gearbox to the ecu, throttle and throttle pedal which is quite time consuming. The whole conversion can be done here at Garage Whifbitz, please email or call for the costs or any questions.