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78 2wd conversion to 4wd


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I just stumbled onto this great site. I found a 78 2wd wagon that is nearly rust free. My 79 4wd wagon is dying a slow insiduous death and I'm thinking of cannibalizing it and converting the 78 to 4wd. So a couple of questions:

 

1. Would there be any major modifications necessary? It appears that all the proper bolt holes, etc are there to attach the rear differential. I know front axels are not the same so its pretty much a drive train swap.

 

2. The 78 has a points distributor. Is there any advantage to trying to use the more maintenance free electronic distributor that is in the 79? Will the 78 wiring harness handle this or would I need to change the wiring harness? Or for that matter should you trust a 36 year old wiring harness?

 

3. I plan to rebuild the motor. Any way to get more horsepower of it aside from bigger pistons? Might the later model 1800 cc engine fit (1980) without major modifications?

 

Any advice appreciated. I hate to put my 79 wagon out to pasture but the body work alone would cost me a fortune. It was even used in a photo shoot in Sedona for a back to school L.L. Bean catalog 3 years ago. They gave me $500 bucks to use it for a day!

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I just stumbled onto this great site. I found a 78 2wd wagon that is nearly rust free. My 79 4wd wagon is dying a slow insiduous death and I'm thinking of cannibalizing it and converting the 78 to 4wd. So a couple of questions:

 

1. Would there be any major modifications necessary? It appears that all the proper bolt holes, etc are there to attach the rear differential. I know front axels are not the same so its pretty much a drive train swap.

 

2. The 78 has a points distributor. Is there any advantage to trying to use the more maintenance free electronic distributor that is in the 79? Will the 78 wiring harness handle this or would I need to change the wiring harness? Or for that matter should you trust a 36 year old wiring harness?

 

3. I plan to rebuild the motor. Any way to get more horsepower of it aside from bigger pistons? Might the later model 1800 cc engine fit (1980) without major modifications?

 

Any advice appreciated. I hate to put my 79 wagon out to pasture but the body work alone would cost me a fortune. It was even used in a photo shoot in Sedona for a back to school L.L. Bean catalog 3 years ago. They gave me $500 bucks to use it for a day!

You should come over here I know of a bunch of 4x4 wags for sale cheap here. (even a running one for 500)

Adam

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You should come over here I know of a bunch of 4x4 wags for sale cheap here. (even a running one for 500)

Adam

Well, thats an option I was considering as well but there's not many left in these parts and the ones that are still on the road are rust buckets. Any of them in decent condition-the body that is?

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sorry but there is no way to convert a gen 1 2wd to 4wd. I have researched it and the underbody is just completley different and so it won't bolt up. It would just be easier to find another 4wd.

 

As for the disty, find an EA81 2wd electronic disty and swap it in. It easy, just connect the yellow and black wires to the coil like they would be on the EA81, connect the vacuum advance line up and plug off the vacuum retard line, and time it. You will probably have to time it by ear because I have never been able to get the timing marks to appear with this type of disty in an EA71. The '79 doesn't have a electronic disty in it. Mine didn't and my FSM doesn't mention anything of it. I do know of the points distys in gen 1's do vary between '78 and '79.

 

The EA81 I have heard will bolt in but you would need the steering rack from an 1981 Brat with the EA81 in it. I also have heard from a friend who did the EA81 swap into his '77 4wd wagon that you don't need it.....I haven't tried the swap myself until I get my EA81TT done for my wagon.

 

I hope this helps answer some questions of yours:D

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Well, thats an option I was considering as well but there's not many left in these parts and the ones that are still on the road are rust buckets. Any of them in decent condition-the body that is?

Several of them decent. I know of 2 that are 95% rust free. (the one I drove in the Junk yard today has some rust in the pass rear QP on the bottom. but there are several (in the same JY) that are in equaly good shape body wise.

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Thanks Racer-x. That does seem the simplest solution if I want to stay in the EA71 4wd game. Definitely a classic.

 

I am surprised, however, from a mass production standpoint that the wagon body style seemingly the same on the 2wd and 4wd that you can't just switch the 4wd stuff over. A quick glance at the under carriage it looks pretty similiar but apparently not. And I was going to a complete rebuild on everything anyway so it wouldn't be that much more work. That is, new boots on the axels, new struts, etc.

 

And yes, my 79 (production date 12/78) does have a stock electronic pointless distributor.

 

Thanks for the input. Joe

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Gen 2's are more friendly, and Gen 3's and 4's are even better. Converting an EA81 can be done (I've done it), but it's not "easy" - takes a bit of work. Converting EA82's actually is pretty straightforward, as is converting a legacy apparently. As Subaru got more into the 4WD and AWD game, the differences between the 2WD and 4WD models became more and more modular to save costs. Unfortunately, the first gen was just too different to really make it feasible.

 

GD

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well since its a California model, it has the pointless disty in it. I totally forgot about those but yeah in all the 49 states, they have the points disty...

 

Actually, it was purchased at the College Park Volkswagon dealership in MD. From the sounds of it I can put any of the late 79 or early 1980s distributors in it? Just swap out the ballast resistor and the other stuff that comes with the Hitachi points model?

 

At any rate I guess I'm going to look for a decent 4wd model and sell the 2wd and use my current 79 as a parts car. Thanks again for the beta. Joe

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well if you find an '83 2wd EA81 with the electronic disty in it, pull it and it'll drop into your EA71. I have one in my '78 Brat and the gas mileage was great with the stock carb, 30mpg with my foot in it roasting the tires:D

Let me see if I'm getting this right. I can drop the 83 2wd EA81 into a 79 4wd wagon? Will the transmission in the 79 mate with the EA81? I'll bet your setup has a bit more omph than the EA71.

 

What is the difference between a 2wd distributor and a 4wd distributor? I'm guessing less low end torque?

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There is no significant difference between the advance curve of a 2WD disty and the advance curve of a 4WD. This is a wives tale, and I'm not sure how it even got started. NOTE, that this holds for EA81's ONLY. EA82's have many different curves for different years/types of fuel systems.

 

Have a look in the FSM if you do not beleive me....

 

One must also be careful to match the correct disty to the correct ignition coil. The resistance values of 2WD and 4WD distributors and ignition coils are different. Hitachi coils go with Hitachi distributors and ND coils go with ND distys. Per the FSM.

 

The difference in resistance probably accounts for the "increase" in throttle response that people feel. The 4WD coil with a 2WD disty will make a hotter spark, but do not mistake this for a difference in the advance curve. Your just asking to blow up the coil or the ignition module by doing crap like that.

 

GD

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