Reconditioned EF head and Cam is now on the EA block. While I had the head off I changed the dizzy to a MPI one since I still had the CFI one from the conversion.
Problems: No power low down. I used to be able to get up my drive in 2nd but now it will bog. From 1200 to 3200 approx it has ok power but nothing like it used to. After 3200 it dies away quickly to the point where I have to hold it flat in 4th to get to 100. The engine also sounds "hollow" if you can understand what I mean. It also got hot doing this but I'd assume this is from it working too hard.
Ive already had a few suggestions from a few reputabe people on mIRC on #eafalcon.
1: Compression is higher and its self igniting.
2: Timing. I cant set base timing because I have a 4.0 auto computer and it won't go as far as leeting me set base timing. Even my friend who works at Ford couldn't and he has all the plug in gadgets.
3. Plugs. These were the ones that came out of the 3.9 head.
4. Cam timing. I did notice that the mark on the harmonic balancer was not on TDC when I had the head off. On the TDC mark it was starting to go down. If I remember right, somewhere between the 2 marks onthe block was TDC. Being a newbie to this (I'm the last person who should have changed a head) I just lined it up to the TDC mark.
What im gonna do now is pop the 3.9 cam back in and try that. Mean while some suggestions would be much appreciated. I'm also going to get a 3.9 auto computer and use that so it will at least let me set base timing. If anyone has a 3.9 MPI manual computer ands wants to sell, let me know!
You checked your harmonic balancer hasn't slipped?
Sounds like that might be your problem. Hmm whats this about not being able to set the base ignition timing, why won't the 4.0 computer let you? I've never had a car with the 4.0 computer, but they would have a similar set-up as the 3.9L which is just earth the self test lead and use a timing light.
Check the harmonic balancer hasn't slipped, and redo the timing and that will probably fix your problems.
I put the 3.9 cam back in and it goes a lot better (well at this point in time it isnt). Its basically like a 3.9 should be but one that has low compression (dues to the head not having swirl ports). My guess is the fuel isnt getting mixed enough and is running inefficiently. The ea head will be getting a recondition and some head work and will be going back on ASAP!
(PS this is NZinAUS, Im at waynes since the damn thing has broken down)
you should be able to set base timing by running the engine till it is hot, then turn it off.
where is the diagnostic connector in your car? is it the one under the dash in the drivers footwell? it should be white plastic.
short the two far left hand side pins, then start the car. it should idle high i think, let it run for a bit till it sorts itself out.
connect a timing light and check timing, it should line up with the mark on the timing case that says IGN (i think thats what it says, but its not TDC!!)
book a dyno run to find out what its doing, they check air/fuel ratios when you do a run, so you can tell if it is running lean. i think this might be part of your problem. if it is, give it more fuel pressure, i can tell you how to do this if you need to know, the mod costs nothing.
you didnt use a CFI intake manifold gasket did you? the MPI and CFI intake manifold gaskets are differnt, if you fit a CFI gasket to a MPI engine it will run like crap.
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I can't set base timing. Even a guy who works at ford who designed the wiring on the AU can't and he has all the plug in diagnostic tools. I need a 3.9 computer as they dont run a trans.
And yes I have the MPI gasket and its about 3mm thick compared to the CFI which is paper thin.
Firstly, the reason you can’t do the base timing is because there are error codes in the ECU. I had a similar problem after doing my manual conversion. It was impossible to set timing as the mark just kept on jumping around, and seemed to be in a different spot every time I checked it.
This was all because I have a wiring error when I bypassed the neutral starter on the ECU when I did the conversion.
If I did a self test on the ECU, it would spit out the neutral starter error code, and exit. The ECU is most likely looking for some sort signal input form the AUTO.
So what you will need to do first is get a 3.9 MPI ECU in there and get rid of all error codes, then set your base timing. Or, you could try to get rid of the error codes with the existing ECU, which ever suits you.
Now, when going from an EA Head to an EF/L head, it's pretty important that you have the head decked, and use a thinner head gasket. This will give you back your compression. Remember that the EA sits at 8.8:1, and anything lower then that aint going to help you out in the kW department I assure you.
It would also be a good idea if you installed a variable cam gear when using the EF/L cam, or any non standard cam for that matter.
The reason you have lost power down low is because of the cam profile of the EF. The EF's ECU has the ability to alter timing at different rpm. It has a similar profile to the ED XR cam, which helps at the high rpm end, however it relies on timing alterations down low, and the dual runner manifold to give it some grunt.
On the other hand, the 3.9 cam was developed to work with a 3 speed, and 2.77 gears, with max power at 4500, and no timing alterations, which is probably why its gong better down low with this cam.
With a variable gear, you should be able to adjust the cams power range so that it gives a bit more life down low.
Keep Us posted.
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Thanks for the tips Simon. Im going to get the 3.9 head machined and a bit of port work (when I can afford it) so at the moment it runs OK but not like it did before. Till then it'll stay the way it is.
What you said about the timing was exactly what the guy from Ford said too.
Well after the dramas on the 24th at the drags I called in to see my friend who helps me out.
My car was throwing belts and it turned out the p/s pump wasnt quite in line so thatr was easily fixed.
The major problem with engine power was also quickly discovered. The mark on the crank pully for TDC was not true TDC of the motor. The pully has slipped about 15 to 20 degrees and made the timing seriously retarded. That was fixed up by finding TDC and belting a new mark on to the pully with a screwdriver and hammer. We checktd the cam was timed properly and it was strangley. So popped it back togeather and he plugged in his diagnostics tool and got a heap of auto box codes etc. Fired it up, away it went. All I can say is Ive never felt it with so much power. I used to think it was ok before I did the head but now it'll smoke the tyres and chirp 2nd. YAY! I just wish I got it done BEFORE the drag day. Maybe I would have got fastest car award?? HAHA
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