As most of you know I'm doing my homework in regards to converting my EFII I6 to V8. My original plan was to buy a complete car however its been rediculously difficult to find a 96 V8 Fairmont with a decent amount of kms. So lately i've been thinking maybe I'm better off buying a conversion kit from a wrecker. This being the case, there are many more possibilities such as the chance to fit a newer XR8 or Fairmont engine. So basically the intention of this thread is to list everything and to get some advice and confirmation as to what works with what and what possible problems these components may cause. Here we go...

1. Engine and Auto
Ideally I'd like the V8 and auto from an EFII Fairmont as to minimise the possibility of software/hardware conflicts however I understand I'm not limited to only this. Possible engines/autos could also come from any EF/EL XR8, Fairlane or LTD as the hardware should be the same.Please correct me if i'm wrong. Not too sure if there are any differences between EF/EL auto trans computers - can anyone confirm?
V8 K frame and engine mounts should be universal across the whole EF/EL range so they shouldn't be a problem.


2. ECU
If sourcing from a EF/EL Fairmont everything should be all good and well however what happens when using an XR8 ECU in combination with the Fairmonts high series BCM? (Fairmonts and above use high series). I know of one guy who converted an EF Fairmont with an XR8 driveline and he has disconnected the climate control because the car hunts (wants to stall) whenever he runs climate. I personally think this may be caused by a conflict between the ECU(xr8)/engine harness(xr8)/BCM (Fairmont) combo he has used. Also worth mentioning that the car blew two BCMs after the conversion (3rd one still going).

This is a prime example of the sorts of problems I want to avoid. I wan't the car to drive and function as if it came out of the factory with the 5 litre.

3. Engine Harness
Again, if sourcing from an EF/EL Fairmont everything should be hunky-dorry. I6 EF Fairmonts have speed sensitive power steering - can anyone confirm if the V8 version also has this feature? Did the Fairlanes/LTDs also have this? I know for a fact that XR8s don't have s/s power steering as there is no provision on the harness. Assuming a Fairmont harness was used in conjunction with an XR8 ECU would the s/s power steering work?

4. Radiator
Not too sure about the radiator specs across the models or series (EF/EL). I assume the same radiators would be used across the whole I6 and V8 range however i'd like confirmation of this. Obviously the hoses would be different.

5. Air box
Again, I suspect the air box would be identical across I6 and V8 variants. Intake plumbing would be the same for Xr8/Fairmont etc.

6. Exhaust
I know the I6 and V8 used the same oxygen sensor however did the V8s have one or two O2 sensors? I imagine they would use one per bank for diagnostic purposes. Not too fussed about the standard setup as I'd be inclined to run a twin 2.25-2.5" system with a pair of 2.5" Di-Fillipo extractors.

Thank you all for your help in advance. I know there would be a few questions in there that a few people would want to ask!!

Anthony

i think you should stick with the 6 and talk to the guys at jim mock motorsport. for the price of the v8 conversion you could get about 220hp at the wheels and run mid to low 13's its worth a look and could save you a lot of stuffing around.

From ED on, correct me if im wrong, but I thought the trans and engine ECU was one intergal unit. Anyway, modifing the 6 you have got would be easer and probably cheaper than a V8 conversion. The 6 in the falcon is the best aussie engine since the 265 Hemi. With the right mods, it pumps out bulk torque, and torque is what makes cars go hard.

I dont know about the 6's but the V8 only went to a combine ecu for box & motor in the au series.

What's a decent amount of kms? Remember that the Windsor's can last a lot longer than the I6s without major maintenance.

Many people have suggested that I should keep the 6 and not bother with the 8 but the fact remains that I don't want a 6 even if its blown stupid and producing 300rwkw. Granted.. its easier and it'll be an absolute ball tearer but I've always wanted a hipo V8. The other problem is that the car is too sentimental so selling it and buying another with a V8 is out of the question. I'd rather spend money on my own car. My plan is to build it up over the next few years and eventually just garage it and drive it on the weekends.
My idea of decent kays for a 96 model would be around the 100-120K mark. Mines about to hit 150K and I personally think its too much. Now I know the average is 25K a year etc etc but for me its too high.

Just a couple of quick points. The XR8 ecu works no problem with a high series BEM. I know this cause i brought mine from AXR88U and have no problems. The 6 has an integral comp for the engine and trans, but the V8 they are 2 separate units. My 96 Ghia came with 120000 when i brought it in march 03, so finding an EFII with those sort of k's may be a little hard, but look around and be prepared to pay for the privelige. For the record, my V8 has just ticked over 180000k with no problems other than usual maintainence, and i am a mad bastard who puts a tnk of NOS through it at least once a week. If that isnt testament to the strenght of these motors, then i dont know what is. I put mine on the bottle at 150000 and it still screams
Brett

Thanks for the clarification Brett. Do you know if the V8 fairmont has speed sensitve power steering like the 6's? If so can an xr8 ecu be used to drive this feature if a fairmont engine harness is used? (xr8 harness doesn't have the plug)

I reckon you'd be better off getting an engine/trans combo from a wrecker and getting the EF fairmont ghia ecu to go with it to make it cheaper. This shouldn't be too hard to source. But you will definately need a V8 ecu.

Fairmonts don't have speed sensitive steering, but the fairmont ghia does. Pretty sure the fairlane and LTD had it, but not sure about XR.

As for the hego sensors, they are different between 6 and 8. The 8 ones have a thicker coat around the sensor - not sure why this is though. And yes, the V8's have two oxy sensors.

Good luck with the conversion

Are you sure that only the ghias had the s/s power steering? I was under the impression that the fairmont 6s had this feature as well.

Also, i'm considering buying a complete Ford workshop manual to help me out. Do these manuals offer explicit details such as how wiring harnesses connect to eachother etc or would I be wasting $250?

The work shop manuals have everything for that. Wiring diagrams show wire colours and where they go to as well as plug types used in various location.

I had an EL Faimont once and it had speed sensitive steering. If you are going to all the trouble to fit an EF V8 you should take the opportunity to change the intake and heads to something better while you're at it - they really suck. Or as you said before, you could go to the effort of getting an AU engine which already comes with better intake and stuff. You should be able to use a V8 EF ECU and minimal modifications around the motor.

Sounds like i'll be ordering a workshop manual this week. Its the eletrical side of things that has me spooked to be honest. I want to know that everything will be compatible and will actually work first time round!

Anyone know the differences between an XR8 and Fairmont engine harness?

I don't think there is any... not 100% sure though.

no EF had speed sensitive. only NL/DL/EL GHIA