18RG to 18RGEU with 22RE electrics

[WHITCHY]

Well it was a long, Aussie day long weekend, and with massive thanks to Joel(TurboRA28) and Scott (ToyT18) we finally managed to convert Anna's 18RG to GEU using 22RE loom and ECU, and still using the standard carby thermostat housing.

Just thought I would make a post in here because I couldn't find any rock solid information about using 22 electrics and not using the EFI thermo housing before we started.

Turns out it is possible, just a bit of a pain in the ass!

To fit the fuel rail we had to grind a chunk out of the thermostat housing, and also grind down the fuel rail, and even then it is still a bit fiddly to get the fuel rail into place with the injectors.

The throttle body also fouls on the housing, we used a 22RE throttle body, because we couldn't find an 18R one, so a genuine 18R one might fit a bit easier. We had to grind away the bottom of the throttle body and then it bolted up. Again because of the thermostat housing, it is not possible to run the TPS. ( I am working on getting it mounted on an extended bracket or on the other side of the throttle body, or possibly on the accelerator pedal(ingenious idea suggested by TurboRA28))

The electronics were probably the least troublesome bit. We used an 18RG dizzy with 22RE internals, 22RE AFM, 22RE wiring loom and 22RE ECU. Once wired up it was running, but very doughy down low, with a big power kick at 5k rpm. After a long time of messing around tightening and loosening the AFM there still wasn't much difference.
The timing was set at about +15, then the timing light broke, so we advanced the timing a bit and it instantly improved.

The intake gasket we used was from the carbys so there is no cut outs in either the head or the gasket to allow for the injectors(They appeared to be on enough of an angle to not be a big issue)
I am waiting on a proper EFI gasket with the cut outs and then I will remove the intake and have the head cut out to match the gasket and see if it makes any difference.

Another issue with the carby thermostat housing was mounting all the sensors, with the EFI wiring there was a small green water temp sensor (tells the ECU water temp) and a big brown water temp sensor(For the cold start valve). The brown sensor was a direct fit into one of the threaded holes on the side of the thermostat housing, but the green sensor had a smaller thread. Our original plan was to drill a hole and tap a thread into the fitting for the water inlet, but insted we opted to drill a hole in a small straight section of metal pipe and weld in a nut with the same thread as the green sensor and mount that in the top radiator hose.

The car is running extremley well, starts easily, idles smoothly, and is just a much nicer car to drive. We will be getting a wideband 02 sensor soon to check out the mixtures and fiddle with the AFM if need be, also need to get a standard 02 sensor fitted to the exhaust, and the TPS mounted. Also need to check the timing. Once these things are checked I will get the results up.

Another major problem we are having is that the car suffers massive fuel surge around left hand corners if the tank is below half, so if anyone is planning an EFI conversion for an RA28, you will need a surge tank!

[brett_celicacoupe]

i would suggest getting a jaycar digital fuel adjuster and using it to trim the AFM signal accordingly.

they have over 100load points and the unit is under $100 for memory.

[WHITCHY]

Awesome, thanks for that! I was going to look into an SAFC if it is running to rich or lean, but the jaycar item sounds a bit cheaper!

[Lambolica]

So all the headache in this conversion revolves around Not having the GUE thermo housing? So the rest is pretty much bolt up.

Nice solid info.... I'll have to dig out the EFI thermo housing and have a play...

Cheers
Simon

[WHITCHY]

Yeah, that was our only problem, it was always in the way! Luckily there was plenty of meat on the rail and the thermo housing to grind and cut chunks out of it! so with the proper housing it should be a very easy conversion! But not for your car Simon! Putting EFI in that would be like River putting an SR20 in his RA25! Its just not meant to be! So sell me your housing!

Cheers!
-Whitchy-

[TurboRA28]

Good one, i'll know what to do if i ever have to do this conversion

[The Witzl]

If you dig back through the tractor engine thread, i've put up pictures of the differences between carby and EFI 18RG thermostat housings.... the carby one is massive by comparison.

http://www.toymods.net/forums/showth...stat#post38378

If you get really bored, you can always run a megasquirt

[bnicho]

Interesting! What intake manifold did you use? 18RGEU or did the 22RE one fit the 18RGU head?

Cheers,

[WHITCHY]

We used an 18RGEU intake, I had thoughts of using the 22RE one if we couldnt find an 18R one, but the 22RE intake ports are spaced differently!
Cheers!
-Whitchy-

[o_man_ra23]

I have run EFI with a carby thermo housing before. It fits, and I didnt grind any off the rail, just off the thermo housing (easier to find a new one if you stuff it). I never had problems with the TPS though, so that may be the 22RE throttle doing that.

Do you have the early 22RE ECU or the later one?? The later one had an oxy sensor input from memory, and the early one didnt.

Is the car blowing black smoke when it is underpowered?? If so, then your just running rich, if not, then you could be running lean (or it could be spark related)

Good work, a few snapshots of the conversion would be nice though Did you hook up a check engine light??

[WHITCHY]

I am pretty sure its the early model wiring, it has a big massive TPS and I have seen a newer 22RE that has a different looking TPS.
The car wasn't blowing any black smoke, it was just running really crappy cause it needed more timing!
Gonna try and get a wideband 02 sensor onto it soon to check out the mixtures for sure, all we did was check the spark plugs, and they weren't too white so looks like its not running too lean or rich!
I will get some pics up soon! Didn't do anything about a check engine light, is it possible?
Cheers!
-Whitchy-

[o_man_ra23]

Just a 3 watt globe stuck in the dash will do... put an amber condom over it and your right. It will flash and tell you all the problems

[WHITCHY]

freakin sweet! Are you able to tell me what wires it needs to run off?
Thanks heaps!
-Whitchy-

[o_man_ra23]

Look in the RWD Celica Haynes Manual, it tells you in the 81-85 wiring diagrams.

[The Witzl]

be careful with the newer 22RE TPS (the smaller one) as they are fully variable and not compatible with the old school 22re ECU.

Sounds like you are having fun there witchy