Just acquired a gen 1 brat with an ea71 and the motor was a little tight because it was sitting for years but we freed it up and got new oil in and everything but still not having any luck keeping it running and im considering rebuilding the motor. Ive already ordered all kinds of parts for doing this while they were on wholesale but im wanting to do it soon but dont really know enough about rebuilds. I have quite a bit of knowledge i just havent tackled a rebuild on my own before so i have a couple questions...

#1 is there a way to get a bit more power? I have my webber coming but i was wondering what i can do with the motor apart to add a bit

#2 pistons and things... do i want to go a bit bigger? if so does anyone have any advice?

#3 anyone know of any good write ups for this?

 

Just hoping people have some advice so i can get this thing done and back up in good shape!

Thanks in advance! 

Hey Bart,

 

I just saved an 80' Brat that had been sitting for 14 years and i just got it running but the carb is all screwed up. I'll probably just buy the weber conversion as well but in the meantime i am planning an EJ22 swap into this thing! I hope someone else will post some good EA71 stuff for you, good luck with your build, we'd all love to see some pics if you can!

1. add a weber carb

2. check the clearances on the motor you tear down, and order accordingly

3. try to get yourself a factory service manual, it details everything you could possibly need.

The How to Keep Your Subaru Alive has an engine removal/teardown/rebuild section which I used the first time I ever went into a motor (an EA71 just like you) and it helped tremendously. It doesn't cover every little detail but gives enough direction to keep you going. As for extra power... good luck and let me know when you find something.

For a bit more power, especially since it will be apart, would be to add a cam. Don't go crazy as a big cam will only really work well with head work. A "RV" type cam would be ideal. As for the pistons, I always try and bore out to the next size, primarily to get nice round cylinders. The amount of displacement you gain is minimal. If you can find high compression pistons (most likely custom, therefor $$$$), there will be a small bump in power there, not nearly enough to justify the cost of usually around $125 a hole. Port matching will net another small gain for little cost, along with a fresh 3 or 5 angle valve job. The bigger gains will come from port work on the heads, but that is $$$$ and would move the power out of your normal driving RPM's.  Best bang for the buck if you are doing a full teardown would be the weber with a nice cam, well rebuilt heads maybe with some port matching/cleaning, and a nice exhaust system. You would probably be looking at a 10-15 HP bump adding stuff you were probably replacing anyways. Unless you go forced induction, there is not a lot of "cheap" power to be had. (not that adding a turbo or SC is cheap)

 

Mark

 

I am ordering this kit off of amazon, for $299 with free shipping and comes with the adapter plate. Not too bad of a deal!

http://www.amazon.com/gp/aw/d/B000JLL04A/ref=ox_sc_act_image_2?ie=UTF8&psc=1&smid=A96SYUVHGPWLJ

 

Here is the link to Weber carb on Amazon if anyone else is interested.

While I have not had any direct experience, nor do I know if this is one, I have heard negative reviews of the made in china webers. I don't know if they are actual licensed versions, or cheap knockoffs, but may want to verify.

Really? Thanks for the tip! I will make sure it really does come from Weber, forgot to order it last night anyways ha.

like sarge said..how to keep your subaru alive got me through my first subaru engine as far as torque specs, valve clearance, and assembly tricks to these split blocks. easy to follow..like talking to a backyard mechanic with a beer in your hand. you will need a donor 17mm(or 11/16'') socket and a grinder to shape it with for a couple of hard to get head bolts. other than that just follow the pdf step by step.

And a set of flare nut wrenches. I did not own a set of those until I got to taking off the spider tubing that goes into both heads.

when installing the weber, what do you do about the tubes coming from the valve covers .

You mean the PCV ?   There's a good write up from Loyale 2.7.     Basically, the passenger side gets fresh air in.  Then dirty crankcase air from the driver side goes back into the intake to be burned.     Yes.... you want this.

Trying to accommodate the PCV lines into the filter that comes with the Weber 32/36 for my EA71

So the little filter that comes with the Weber works great for the passenger side crankcase breather line - but what do you do with the dirty, oil and fume-rich driver side?  Rather than adding to the spaghetti nightmare or just letting the crankcase vent to my engine compartment, I elected to use the stock GL air cleaner.  Plus, being a maintenance hoarder, I'd like to get some use out of all those oval GL air filters I've stocked up on. 

 

The problem was going from the rectangular weber intake to the round opening in the air cleaner, allowing for the tilted angle of the stock air cleaner, and providing clearance above the alternator whilst closing the hood. 

 

I probably could have fabbed a connection between the bottom plate of the rectangular Weber filter housing and the top of the round hitachi spacer.  But trying to braze chromed sheetmetal to aluminum or pot-metal is not my idea of fun.  

 

I elected to use the Omix-Ada 17704.02 Performance Carburetor Kit Adapter. This part is normally US $80 via most of the normal sources (like Summit Racing) - but i found it being cleared out on Amazon for US $13.           SCORE!

 

1)   20 minutes of grinding and polishing with a Dremel to take off the sharp edges in the air intake of the adapter to allow for better airflow. 

2)  Then a little grinding round the top edge of the adapter to allow it to nestle into the bottom of the stock air cleaner. 

3)  Lastly I used a rubber toilet flush valve ring ($2 at your local hardware store) between the adapter and air cleaner.  They come in a variety of thicknesses from paper-thin to almost an inch and in a variety of tapers. Take the adapter or the old gasket off your hitachi carb with you to get the diameter right.. although it appears that there is only one diameter and it is exactly right.  I found a 1/2" thick hard rubber O ring allowed the stock air cleaner to mount on top of the taller Weber carb without rubbing against the top of the alternator or being pinched by the hood.

 

The vacuum tubes from the manifold to the old Hitachi all get blocked off.  Keep the breather and vacuum tubes that run into the air cleaner.   

I have been wanting to adapt the original air cleaner to my Weber every since I got my Brat. And I don't even have the original air cleaner! 

 

Thanks for the tutorial. I'm all over it now.

I always wondered how you get all the vacuum advance/retard functions working properly with the Weber, and I guess the answer is you don't and just run on centrifugal advance.

My weber fed ea71 just runs off the centrifugal adv. Seems to do just fine.