MickyG's MX-73 to 7M-GE Swap

mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
Yeah, that's all I'm using at the moment. The secondary isn't an option on cars over here, no matter what year. From my own research last night, it looks like the sub sensor is a different sort of device to the primary. They've got different part numbers from Toyota, different heater resistances (when comparing the turbo heated sensors to the n/a sub sensors) and potentially different methods of operation.

Having said all that, it looks like my best bet might be to just buy a big heat sink'd resistor and be done with it!
 

mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
Pic of the engine bay:
p639484_1.jpg
 

mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
I do. I'll see what I can dig up for you.

Wait, do you want the Supra M1 connector? I cut that off and spliced it into the MX73 wiring. I should still have a pic of it before though. Let me know which one you want, I think I have both.
 

mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
You're a funny man! I'd love to go turbo but I'm pretty sure I'd wake up one morning with the turbo instead of my wife!

Yeah still waiting on the resistor thing. I check for codes every week or so and it's just 27 so no huge issue. I still haven't figured out whether it causes any failsafes. My fuel economy is around what it was with the 5M so I can't complain much.
 

mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
You know, I thought it was just a minor upgrade (not knocking it, mind you) but tonight I really planted my foot and above 4 grand, it's a totally different engine! And that's with my massively restrictive exhaust. I can't wait to put the 2 and a quarter on (of course you've already got that!).

On occasion it's nice to know that it was all worth it! ;)
 

mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
Long overdue mini-update:

Car's still going strong. Hasn't leaked any fluids since I found the last coolant leak about 4 months ago. It has about 3500 Kms on the new engine and fuel economy seems to be getting better (last fill up was 12 litres per 100kms or about 20miles per gallon). Whether that's my driving style, proper break-in, better driving conditions (I recently changed jobs) or something else, I'm not sure.

I'm still putting up with the MIL for the 2nd 02 sensor and routinely checking for additional codes but it's been happy.

I did a head stud retorque yesterday and was pleasantly surprised to see everything under the valve covers sparkling clean! In fact, I think the cams were actually less oil stained than when they went in! Everything was silver, no brown staining on the alloy in the head at all. I guess this is what a new(ish) engine with good oil is meant to look like!

Last little nagging problem of late is an ignition induced buzz that only happens through my FM radio in the head unit. CD is clean and I'm not sure about AM. After looking around a bit, it might be a grounding issue. I'll attack the engine with a heavy gauge wire and see what happens.
 

JustAnotherVictim

Supramania Contributor
mickyg said:
(last fill up was 12 litres per 100kms or about 20miles per gallon)
Thank you for that. :biglaugh:

In my experience so far any buzzing through the radio was from the speedo cable, since I've never worked on your type of vehicle I can't say if the cable is close enough to cause that kind of interference. That nice buzzing is always a joy to listen to eh? :sarcasm:

Glad to hear it's all going well.
 

mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
Thanks man! Speedo cable eh? Hadn't thought of that one. I'll listen a bit closer today and see if that's possible. I found I'd left a ground strap off after the build. I wasn't sure where to put it but tied one from the exhaust side of the head to the firewall.

I really couldn't tell any difference between grounded and ungrounded though. In fact, it sounded fine. But then again, I didn't drive it. I just sat it there in the driveway and reved on it. So you may have something there Ric!
 

mickyg

7MGE MX-73
Sep 15, 2005
406
0
0
46
Melbourne AU
It's been a fun ride but it's time to wrap it up. If anyone in Aus is interested, the car's now for sale. We've had a new addition to the family - a great little boy and priorities have shifted a bit. We've also got a new car to deal with all the stuff that goes with a baby (complicated little things!) so the third car must go. I've "upgraded" to a '95 Ford Telstar TX5 (Mazda 626 but in hatchback form - 2.5l V6 version) but it'll never be the same. Still it's a bit more practical and doesn't need "finishing" like the Cressida does.

Going cheap to a good home!

Thanks again to everyone who provided their advice, comments, assistance, and occasional counselling. I'm a better man for the experience and I'm sincerely grateful for all the help and new friends I've made in the process.
 
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