Setting the Tigers Free

With the engine installed for the last time, it is time to finish and tidy up the wiring. Luckily, my extensions left plenty of slack to mount the ECU where I wanted, in the RAV4’s factory location. More bent steel brackets, but far from BOM-spec. I am unreasonably happy with those ECU mounts.

To integrate into the stock RAV4 harness, I used the factory RAV4 ECU connector and soldered wires to crimp onto the 2AR ECU. This connector is actually intended for an SW20 MR2, but it turns out they are the same. I then epoxied this connector to encase all of the solder joints. There is no "proper" mating receptacle for this connector, so I chose to do it this way rather than repinning it into some other connector. If I find a need to change this in the future it would be a trivial replacement. If this proves an unreliable connection then I will instead just crimp the 2AR ECU wires directly to the RAV4’s harness and skip an intermediate connection. With that, as far as I was aware, I had all of the wiring done at least enough for a test

First try, crank, nothing. Apparently I forgot to plug something back in months ago which was the main power supply to the ECU connector. Second try, nothing. I forgot to plug the ECU connector back into the ECU. Third try, I still couldn’t quite get the ECU to “wake up”. Turns out I just needed an IGSW pin, for the temporary setup I just shoved a spade terminal in the cigarette lighter plug. Fourth try…

Once I saw the throttle body was awake and moving with pedal input, I knew that was it. Honestly I was still pretty shocked it just fired that easily. In that video I was almost questioning reality for a second, I wasn’t sure that what I was experiencing was real. Very surreal experience, 10/10 would recommend. That was just quick, weirdly so. Strange that it just really didn’t have issues.

This means my wiring worked, and I didn’t horrendously mess something up with extending and repinning. Power and signals are going to the places they should, so I need to loom it. Of course that means it’s time to build the exhaust.

The Megan Exhaust header I purchased had an extremely warped flange. This is not all that surprising, cheap eBay parts usually go that way. I got it resurfaced, threw it on the motor, and began cooking. This took many attempts of cutting, fitting, cutting again, grind here, cut there, but I ended up getting clearance everywhere I needed. I ended up slightly notching the pinch weld of the longitudinal member, I will later weld this area back together. Excuse my goober welds, it’s what I could do for the task at hand. This section ends just past the subframe, I can do the rest at a later time and it should be much easier

Due to the very low clearance, I added a small amount of gold foil as a heat reflective barrier in a few spots on the subframe and oil pan. It may do nothing, but it isn’t going to hurt. It’s the count that thoughts.

With that section crossed off the list, I can loom the harness. So of course I make intake brackets. This is strictly temporary, it does not cover my bases and in fact I’m not even using that intake filter pictured. This was a temporary solution so that I could mount the MAF sensor to run the car properly.

How’s that for rigidity, Alex?

The only thing immediately preventing the car from driving now is the cooling system. I just needed to accept that the stock radiator was not going to work. I didn’t love the S13 radiator I’d fitted previously, so I took another gander. The best option I found was a brain child of Dillon Kovacs, who has a gen5 3SGTE swap 4 door. He found that the best radiator to use was that from an ST205 Celica GT-Four. Surprisingly, despite not being sold in the US they were still on the cheap side. These are easily available in aluminum which means I can move the ports wherever I want willy nilly. The bottom outlet was easy, the Tacoma thermostat housing I’m using is the same size as the MR2, and I had an old MR2 radiator sitting around that I could steal the port from. Easier than rolling a bead myself. The top was a little more difficult, the place I had to move it was a low spot on the radiator, so I had to weld in an entire new section to release trapped air.

This was my first aluminum welding project, so overall I don’t think I did too bad. It’s not pretty. Getting metal to stick was easy, making it seal was the hard part.

One small but really bizarre thing I ran into. I needed to add 2 more terminals to the OBD connector, that the RAV4 did not originally come with. I couldn’t quite identify what terminals it used, so I figured I’d pick up an OBD pigtail from a junkyard RAV4. Well the RAV4 wasn’t actually at the yard, but a 1999 RX300 was, and the connector looked the same so I took that instead. As it turns out, the termainls must have changed at some point between 1996 and 1999, because the RX300 terminals do not fit in the RAV4 connector. Weirdly, the RAV4 terminals do fit in the RX300 connector. RX300 connector also clips in to the stock RAV4 bracket, so I just ran with that instead.

Decided to give the car some sun, and give myself a chance to clean out the garage. Looks good with the OME lift kit I installed. With all this plumbing and welding, it was a mess. Plumbing is not done, but it is close. The radiator seals, but I need to find a good lower radiator hose, fix the expansion fitting (oh yeah, that stripped), add mounting provisions to the wiring harness, add cats, resonator, muffler, rebuild the rear suspension, blah blah blah. I’ll take the wins I’ve made so far. I can feel the first drive is iminent.