2JZ powered A70 conversion
 Technical write up on the installation of a 2JZ-GTE and Getrag 6 speed into an A70 Supra chassis.

  
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6 speed 2JZ-GTE Twin Turbo conversion

Installation of a 2JZ-GTE complete with 6 speed transmission into an A70 chassis - they said the 6 speed couldn't fit,  would have an un-useable set of ratios and the shifter would be too far back - what a bunch of fuck tards.
Saturday, 5th April 2003.
The conversion has officially begun, with my Supra being taken off the road for the 7M-GTE to be removed from the engine bay - so long sucker!!!!!.

The total removal took around 6 hours in total, It could have taken less however I was doing most of it myself, and a lot of other parts were removed including the ECU, tail shaft and the exhaust system.
       
Thursday, 10th April 2003.
I negotiated the purchase of a JZA70 cross member, this included the power steering rack and wishbones, this set me back $180. After around 8 hours of labour and removing the 1JZ from the cut, we rolled it over and removed the cross member, a pain staking long day, hindered by not having the correct tools  - It was lucky I brought my trusty air tools and little air compressor :)
Saturday, 12th April 2003
MA71 (Pre 89) cross member removed and replaced with the JZA70 cross member.
                       

       

Sunday, 13th April 2003
At long last, the 2JZ with the Getrag V160 fitted is installed into the car!. And as expected going off previous measurements, the tunnel doesn't require major modifications - 2 very simple modifications are required.

JZA70 engine mounts and insulators have been used. If you can't buy these second hand, below are the part numbers.

12311-88400 : Engine mounting bracket, Right hand side.
12315-88400 : Engine mounting bracket, Left hand side.
12361-46040 : Engine mounting insulator (you will need 2 of these)
12381-42030 : Engine mounting stabiliser (you will need 2 of these)

Firstly, the left hand side gearbox tunnel mount point needs to be hit with an engineering stick (hammer) mid way up, this is due to the R154 being larger on 1 side, thus the tunnel is not centred down the middle of the car.

The second spot is on the right hand side, around 36mm (1.5") in front of shifter hole, a firm hit with the engineer's stick will be plenty.

The rear turbocharger (or secondary turbocharger) fouls the brake booster heat shield. This is easily solved by removing the heat shield and removing part of the mounting bracket from the aforementioned shield -  remember, the JZA80 doesn't run a heat shield on the brake booster so this shouldn't pose any problems in the A70 chassis as the outlets on the turbochargers are away from the brake & clutch masters.
           
Saturday, 19th April 2003
It's been a week between updates, but here goes....

The V160 shifter cradle and linkage rod has been marked out for modification, 4" needs to be removed from the length of both the bracket and the linkage rod, I will now need to organise a time to have them modified.

Measurements for the 1 piece tail shaft has been recorded (1255mm end to end) and the tail shaft has been ordered, I expect to collect this next week sometime.

Intercooler piping has been cut and marked for welding.
Thursday, 24th April 2003
Power steering lines installed, gearbox cross member measured and drawn up, factory JZA80 speed sensor removed and compared  with the R154 speedometer drive unit (The differences here are 2 teeth, with the V160 sensor having 31 teeth whilst the R154's unit has 33.
   
Friday, 25th April 2003
Radiator fitted with factory fan shroud  and 2jz fan fitted - It looks like it was meant to be!
Due to the 2 Air con fans on the radiator, a 45 degree bend couldn't be applied to the throttle body, instead a 3" Silicone 90 degree bend with a 2.5" reducer has been used. I'd have preferred the 45 degree bend as it means the air flow doesn't need to be forced around a sharper bend, but it wasn't to be and the above silicone bend was the compromise.

Wiring has begun, and going back and forth with the wiring diagrams and double checking everything, most of the body wiring is complete including the JZA80 Fuse box which replaces the factory MA71 item.

1JZ Top and Bottom radiator hoses have been used, part numbers are as below.

Radiator Hose, Inlet (Top Hose) 16571-46030
Radiator Hose, Outlet (Bottom Hose) 16572-46100
               
Saturday, 26th April 2003
Wiring has been completed, and the engine is given it's first test fire - smiles all round as the 2jz bursts to life, many thanks to my brother, Adam and my close friend Nick for their help with the wiring, without them I doubt the wiring would have been finished so quickly and been done so neatly.
Saturday, 3rd May 2003
1 piece tail shaft has been fitted as has the custom gearbox cross member, modified shifter cradle and linkage rod
              
The tail shaft  has a built in slip type system which allows for any movement in the  engine & gearbox on their respective mounts. The JZA80 runs a rubber damper on the differential which effectively does the same thing. Custom gearbox cross member fitted.

The factory V160 electronic speedometer drive has been removed and replaced with the mechanical item from the R154. A 1" hole has been drilled to allow the speedometer cable to come through and connect up to the speedometer  - This must be done if using the factory cable as there is not enough clearance to run the speedometer cable up the transmission tunnel and then into the cabin via the firewall.
           
Sunday, 4rd May 2003
Radiator and all coolant hoses have been fitted and all hose clamps checked for tightness. Distilled water and Toyota Long life coolant has been added (it's the red stuff)

Intercooler piping fitted. All that's needed now is for my old 3" mandrel bent exhaust to be modified to fit onto the new engine  :)
    
Monday, 5th May 2003
After spending the best part of a minute deciding whether to drive the car to the exhaust shop or have it towed, I opted to just drive it and at 7.20am I drove the car to work - it's loud with no exhaust, but it's certainly not offensively loud.

1 problem I noticed was the speedometer wasn't working but the PPS was, for a second it didn't click, then the penny dropped - Due to the Speedometer drive gear being located on top of the output shaft on the V160 it was spinning backwards and winding the odometer down! (The gear is meshed with a worm gear on the output shaft so depending on if the speedometer gear is above or below the output shaft will define which way the speedometer gear is driven).

In the case of the R154, it's located underneath the output shaft. So the solution here is to construct a box with 2 simple gears in it to reverse the direction of the speedometer cable*.

After arriving at work I made the call to book the car in to have it's exhaust done however due to them being busy this would have to be done the following day, so the car was to sit at work over night.

*This is something I haven't managed to get around to doing, as a result I have re-installed the original electronic speedometer drive and am running an Apexi speed cut device which not only removes the 180km limit, it also gives me an accurate and working digital speedometer.
Tuesday, 6th May 2003
I caught the earlier bus to work so I could get the car to the exhaust shop by 8am. By 10am I had the call saying the car is ready for collection. $230 later and I was on my merry way. First thing I noticed was just how quiet the car was with my old exhaust fitted compared to when it was fitted to the Anchor M (7M-GTE), it's amazingly quiet, and damn does it sound sweet when it comes on boost.

I had to get back to work so I only gave it 1 good squeeze of the go pedal however something wasn't right, the second turbo wasn't coming online *gulp*. I didn't have time to worry about it as I had to get back to work.
Friday, 9th May 2003
Due to my week being busy, I never got around to finding the fault of the secondary turbo not coming online, however it was as simple as doing the general checks - wiring and connectors :). I began to check all the connectors, and before I got through checking them all, I found an orphan connector - which upon further inspection turned out to be the EGCV. After connecting it I checked the remaining connectors and found no faults.

Time to test the fix, I brought the car up to operating temp, and found a nice quiet stretch of road, 2nd gear was selected with the revs being around 2000rpm, I gave the go pedal a full squeeze and was left with copious amounts of wheel spin as the 2nd turbo came to life.