Thanks to a refferal (thanks shah!), Alex got in contact with me about travelling to Italy to convert his Supra from a HKS FCON setup to a Haltech Elite 2500. With his Supra being a facelift VVTi with ETSCi throttle, its not impossible but certainly harder to find plug and play kits that work with this version of Supra.
After speaking about his requirements, we decided it would be best that I make him a patch loom that adapts his stock engine harness to the Haltech ECU, with a small sub harness for the new sensors we wanted to fit.
He then mentioned he has a friend Trev with an Aristo that was looking to optimize the fueling and power on his BPU aristo that was still on stock management. He managed to source a HKS patch loom, Link kurofune and sensors to control the show, essentially piggybacking off the Stock ECU control.
Aristo's can be a bit funny as its one of the first toyota cars that moved to a BEAN communication protocol, essentially digital communication between electronics rather than analog. It makes the platform quite sensitive to changes, and the wrong modification can put the car into all sorts of limp modes and strange behaviour from other electronics on the car. I was dreading the aristo a bit as it could be a headache and it was, but not for the reasons I expected.
Upon landing in Italy Alex & Trev met me at the airport and we headed off to see the Supra and a while talking the plans over and checking out the car. Soon after we got to work removing old electronics, installing new sensors, redoing vacuum lines and I got my patch harness installed. Hit a snag not being able to connect to the ECU and was dreading that I had made a critical error on the patch harness, but later narrowed it down to my macbook not playing ball with the Haltech USBA drivers, luckily always travel with two laptops so booted up the spare windows laptop, and we had connection, phew. Loaded up a basemap I had prepared on the plane and went through and checked all the I/O.
The following morning spent some time wiring in the new oil pressure/oil temp/fuel pressure/fuel temp/MAP/BARO & lambda controller. Also made a change to the fuel pump wiring so it didnt run constantly and the fuel pump relay was ECU controlled so it could prime the sytem and turn off in the event of a crash/engine stall. Soon after got the engine fired up, checked base timing, setup the throttle, idle control & VVTi control. Immediately the car was idling much healthier than before and with a bit of tweaking got the iconic 2JZ cam idle noise Alex was after as he had some big cams that sounded a bit tame previously.
After a few checks, we went straight into some road tuning on the way to cars and coffee meet, trying some low boost runs and listening for knock to see how good or bad the 95 octane Italian fuel was. Everything so far was reacting as expected and other than dialling in the tune was off to a good start. Spent the rest of the day tweaking various bits, dialling in and finding the limit of the 95 octane fuel.
The next day we worked on the cold and hot start tuning on the Supra, and let Alex get some miles on it to burn off the 95 fuel so he could fill it with 100 octane fuel before the dyno session booked for the next day.
Whislt Alex was out doing that me and Trev got stuck into the Aristo. In theory the Link Kurofune is plug and play with a HKS patch loom, but found out the loom had been modified previously. HKS also wire their injectors and coils in terms of firing order, rather than cylinder order, which can be accounted for in the Link software, but I had a bad feeling about the loom so decided to go through it all on the bench, removing anything we didn't need, repinning injector/coil assignments, adding in new sensors that we needed. Also made the decision that everything we were adding needed to be done in a way that was actually plug and play, so we could swap between OEM ECU and Link Kurufune incase we ran into any issues.
With the patch harness for the Aristo ready for testing, we put it to the test and got the engine started. All seemed well until the OEM ECU started throwing an error code which had a very vague description for the issue and the ETSCI was disabled. After some headscratching and checking over each circuit on the patch harness I finally stumbled across a wire that had previously been modified on the epoxy that held the wiring to the patch harness. It looked solid from the outside but the previous installers efforts left a wire that was on the edge of shorting if you looked at it funny.
Turns out the wire in question was a power wire to ETSCI, so after fixing the wiring we finally had a stable and well running engine! Few trips around the block and confirmed that everything was working as intended and we began to make plans to start tuning it properly the next day.
The next morning we met at a local speed shop to use their dyno and see what power the Supra could deliver.
Other than splitting a wastegate line that was quickly fixed we had a pretty smooth session. Had a decent base to start with on the map from the road mapping, so could focus on dialing in the VVTi & boost/timing for 100 octane. We settled on 1.8 bar boost, 686hp and 780nm of torque. Plenty to have fun with. Finished off setting up the rolling anti lag and done.
Naturally went straight onto the road to test the new settings and had a blast with Alex digging the new power. To finish off the Supra I wired up the ABS speed sensors to ECU so we could turn on the traction control and a rotary dial on the dash so Alex could choose what fuel/boost/traction control maps he wanted to use on the fly.
After the Supra we dyno'd the Aristo on the stock ECU for a baseline and it made some fairly meh numbers. Back at base, we reinstalled the Link Kurufune and started tuning the engine. With control of the boost solenoid, we were able to pump the boost up, get the fueling & ignition timing dialed in. We didnt have a chance to get it back on the dyno to see the changes, but later than evening there was some mexico action against a single turbo SC300 that used to leave the aristo behind, but now it was a dead even race, usually with the aristo taking the lead depending on how clean the start of the pull was.
So mission complete, both cars dialed in and working better than ever, two new friends made and good times had. Quick trip back to the airport and a short flight back to the UK. Michael Yazgic - 0x33