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EA81 with Turbo and SPFI...


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Howdy yall, I got a question. Im tossing around Ideas for a vehicle I recently aquired, its an 86 Turbowagon. I dont like EA82 Turbos. EA81 Turbos are rare. I want it to stay turbo, but i want it to be reliable to some extent. I plan on lifting it 6 inches and doing something with the paint, and I realize turbos arent the greatest for offroading, but it would still be cool. SO, Anyways, I am looking for any advice on wether or not EA82 Turbo pistons can be used in an EA81, and if the SPFI sytem from an EA82 will be able to work with the EA82 turbo or an upgraded unit. Thanks in advance

-Bill

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Contact Rguyver for the details of how he built his hatch back in the day.

 

It had an SPFI powered EA81, EA82 turbo, intercooler, NOS, and he used a second boost triggered "dumb" injector to enrich the system under boost. It ran like a madman apparently, but the SPFI doesn't like positive manifold pressure and goes all funny trying to compensate - thus the extra injector - plus you'll need to reinforce the stock intake bootie - it will blow off under positive pressure. Interesting project but I would be using MS if I tried some nutty stuff like that.

 

And I wouldn't go much over 5 lbs on a non-turbo engine. If you are going to use the low comp. turbo pistons you should use the EA81T pistons as they are a better match for the EA81 block. EA82T versions might work as well but I have no reference for any top shape difference due to the valves being reversed.... I simply don't know for sure. EA81T pistons should work fine and yeild the same ratio. The SPFI will not like the low compression nor the positive pressure under boost so if you do both I would sugest doing MS so you can customize the tune.

 

GD

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Thank you GD, thats exactly the kind of info I was hoping for. I figure getting larger, higher tensile bolts for the manifold, as well as some kind of "better" head stud set up (for lack of a better term) and metal head gaskets and a custom fuel management like Megasquirt, and an intercooler, stiffer valve springs, maybe a little more boost would be possible? Ill have to look at the differences between the EA82T and EA81T pistons, I figure the EA82 parts would be easier to come by and would still be low compression. How reliable do you think something like this could be, Im aiming for about the same power as a mildly hopped up EA82T, so like 115-120 hp?

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All that will cost a good bit more than an EJ22 with more power out of the box.

 

Contact RAM engineering - they will set you straight with what you need as far as internals. The head gasket/stud setup should be fine without modifications, but you will need a cam, roller rockers, and you might consider the dual port heads if you want that kind of power. They build 200 HP EA81 Turbo's for the experimental aviation community.

 

GD

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eh, not really lookin for a RAM motor, way out of my price range. I may try mixing and matching parts from other kinds of motors, but who knows. it'll prolly be a while before any action is taken on this rig anyways, knowing me, I can start a project just fine, finishing it is the problem :-\ Already got about 10 car projects goin, all stalled, not to mention trying to get started remodeling the house Im movin in to. Maybe its time to re evaluate my priorities...

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They sell just parts too, but I know what you mean. They aren't cheap.

 

I have way too many projects myself. Setting up my garage/machine shop has taken most of my spare time lately it seems. That and fixing broken cars for friends - which I'm taking a serious look at no longer doing for the majority of them. I simply do not have the time between the lady, the best friend, work, home, garage, and everything in between. Sometimes I just wish I could go back to pleasing no one but myself. I want to divorce the world - throw my cell phone in a lake and just sit in my garage with the things I love. I think I could be happy as a hermit.... as long as harbor freight was nearby :lol:

 

GD

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Ideally, if you want to go turbo and stay away from EA82, your only reliable options are an EA81 Turbo (hard to find) or an EJ22 Turbo (Engine Swap). Either way, you're looking to spend money.

If I may ask, Why not the EA82T? Personal preference, or power, or reliability? If you take care of them, the EA82's will last a long time, and take plenty of abuse... as long as you watch your temperature and oil pressure.

An EJ swap would be the most cost efficient, in the long run, but if you have to run the worry of emissions / smog checking the vehicle, that may be an issue. What is boils down to is what you are looking to get out of upgrading VS. the cost of doing either swap.

The EA82 SPFI assembly is fairly friendly to upgrades, as long as fuel management is addressed. As stated above, extra fuel injectors are necessary when putting this system under boost. The Airflow Meter cant really keep up, and the ECM does not like positive pressure (boost). Ultimately, stand-alone fuel management such as Megasquirt or SDS would be necessary, depending on how far you take it.

The EJ22T is pretty much set up, lots of power readily available, and plenty of upgrades.. but, you have to find an adaptor plate and modification is necessary to a lot of stuff, including wiring, engine management, cooling system, fuel system (high-pressure VS low pressure), etc. so it's fairly labor intensive... However, the gains are impressive, the reliability goes way up, and there is plenty of advice on EJ swaps in these forums.

GD, LOL @ "Want to divorce the world" !!

Also, the EA82T pistons are square-dished and centered, and should not care about valve arrangement. I dont suspect you'd have any problem using them in an EA81 application, but I may be wrong.

Good luck!!

88RXTuner

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The main reason I want to go with an EA81 version is I like the no timing belts, and its a direct bolt in to the EA82 wagon. Also, I like having something that most people would just kind of overlook. EJ power would be cool, but its just not for me. Actually, even getting into simple fuel injection is a little out of my realm, but I want to try something new. As for the EA82T, aside from the various horror stories of blown motors from upped boost, repeated head gasket repairs, and timing belts, the EA81, one of the most reliable designs ever, seems like a better platform to start from. Thanks for the input guys!

-Bill

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