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EA81 power


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There's some sources that claim 74 HP for the hydro lifter engines vs. the 73 HP of the solid's but there's other sources that discount it.

 

The short answer is *no* for the US market. Other markets had variations on the EA81 that produced as much as 108 HP (JDM dual-carb RX engine). The differences in the RX engine was largely in the head castings, valve size and placement, cam, and the compression ratio (pistons).

 

Unless you count the EA81 Turbo's made in '83 and '84. Those had 95 HP.

 

If you want big power from an EA81 you are pretty much stuck doing it yourself.

 

GD

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If you want big power from an EA81 you are pretty much stuck doing it yourself.

GD

 

Or buy an aviation EA81... 100HP for the NA, or 140HP for the turbo variety. Kind of pricey IIRC (think breaking 5 figures for the turbo one) :eek: And... I'm not sure, but you probably have to run aviation gas at the higher compression ratio they modify them for.

 

Z

Edited by zyewdall
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alright that's what I figured, I'm not after power out my EA81, I knbow better I was just curious. I have another motor kickin around and if there was any substantial difference then I was thinking about resealing it and dropping it in but thanks guys you answered my questions!:grin:

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I dont know why, but I definitely felt a power difference when I swapped muy '82 EA81 motor for a '86-ish EA81 in The Beast, the new motor feels like it has a bit more torque than the old one, and i think thats because the Hydro motors have larger valves than the solid lifter motors, but I did also replace my Ford 2bbl carb with a 32/36 Weber. I could just be thinking with my a$$, but to me it felt like there was a difference.

-Bill

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I would think large valve EA81's would be better then the older small valve ones. But I have no idea when or what both those models came in. Also make sure your strut tops are in the "Wagon" setting and not the "sedan" setting. As this will give better caster as well, only a little though.

Edited by Phizinza
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Yeah the motor I have in it now is an EA81 out of an 83 or 84 hatch and the spare that I have is out of an 86 Brat so I guess by what your saying I probably have the bigger valves already. I also have SPFI so I can't really do any upgrades to that:-\

 

Phizinza, what do you mean wagon setting vs sedan setting? I have Loyale strut tops in my Brat so I used the existing hole in the front and then drilled to in the rear

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Since you are using Loyale strut tops the "wagon" or "Sedan" settings on the strut top dont apply.

 

On the EA81 and EA71 strut tops the spot where the strut bolts to it is not in the center. There are markings with arrows on either side, on the short side it has "sedan" stamped in it with an arrow to the front, and on the long side it has "4x4, Hatch, Wagon" stamped with an arrow.

-Bill

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I dont know why, but I definitely felt a power difference when I swapped muy '82 EA81 motor for a '86-ish EA81 in The Beast, the new motor feels like it has a bit more torque than the old one, and i think thats because the Hydro motors have larger valves than the solid lifter motors, but I did also replace my Ford 2bbl carb with a 32/36 Weber. I could just be thinking with my a$$, but to me it felt like there was a difference.

-Bill

 

different engines just have slight tolerence differences ive had the same, the old field basher used to fly! but my road one just dont seem to have the same go really, and the other engine was strong, ive had 2 now that are blowing rings very slightly (it'll be fine!) lol and neither seemed to go quite as well, thats why a blueprinted engine will go so well, cause all the tolerences are to a minimum, your just lucky if u got one that is slightly better than another, slightly more blueprinted

 

Well... Yes, but there`s Another Board Member Runnin` his EA81 Brat with Parts from "SUB4" Airplane Engines... Expensive but Right Bolt in, no Engine Swap Needed... :burnout:

 

hey hey! lol!

 

best cheap mods to give an EA81 a bit more go, cheaply, port the heads a bit, get the cam done, and the old skool way, skim the heads, somin 2 do with timing is a bit of an issue cause of it im not sure i cant tell u, run larger spark gaps, some advance, good qual plugs and leads, and if ya can, make up a twin carb setup or at least get a good carb on it, and your be good for quite a bit more!

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  • 2 years later...

I have a rebuilt EA81 Turbo that I can't power up. The turbo is replacing a carbEA81 that is in a hovercraft (not only airplanes love these things.

My problem is in the hovercraft world , no-one can figure out the wiring. I really want to get this machine up and underway. How do you source wiring diagrammes and how do you make the computer forget its not in park and all those other feedbacks from a transmission. The trani is long gone and the propeller drives right off the shaft sticking out of the bell housing.

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Well your first problem is not having me there to go for a ride with you!! LOL

I don't know what to tell you other than hook everything up as if it were in the car. ECU and all the sensors. You should be good to go. I have no experiance with those set ups but I don't think you need worry about not having a transmission and such as I don't believe the 2 communicated at all. I know they don't on my 1993 EA-82. Oh. You are welcome hope it helps.

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I thank you for your advice, the manual is loaded and it apears to be different from the one I have ,so hope it works. There are a few of these hover out here , the tide goes out about a mile so we can use the sand to move around on. like an airplane but you only fall8 inches. Adventure for the cowardly. This particular hover is

 

They move along at about 40 MPH and use very little fuel.

That is when the engine is running otherwise its just a big log in the water or sitting on the beach.

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