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Pistons for EA-82


glenlivet
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Hi all,

 I have a MPFI Turbo EA-82 I am rebuilding for use on a rather largish hovercraft I have under construction. I plan to use the Megasquirt and Spark Fuel Injection/Ignition controller to run it but I'm concerned about trying to use a turbo on an engine that will have water spray around it constantly and how to keep water from getting sucked into the turbo. In studying the Soob factory manuals I'm not so sure a turbo is runnable (if that's a real word) without the original factory brain box anyway because of the RPM kickdown controls,etc. on the turbo that there is no functionality for on the Megasquirt. In my research I've found that there are three different pistons in the EA-82, aspirated(carb) MPFI and MPFI + Turbo. The tops of the turbo pistons (which I have) are dished out pretty significantly. As the bore size is the same on all the EA-82's is it possible to convert a MPFI+Turbo to a MPFI only by just replacing the pistons and eliminating all the extra "junk" associated with the turbo? Has anyone in the forum done this conversion to an engine that they were going to use ouside of the car- say, on a light airplane or gyrocopter? Or, has anyone come up with a way to run the turbo without the factory brain? 

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Turbo or not, you don't want water getting sucked in the intake.

 

What made you choose the EA82 platform over the EJ? IIRC the 1.8l NA EJ18 makes more power than the 1.8l turbo EA82T and the EJ18 is incredibly more reliable. When doing an EJ18 swap the entire engine harness comes out as one piece and all you have to do is splice into two connectors. The weight and size difference isn't much, they're just engineered better.

 

I don't think a lot of people will argue that the ea82t is the worst engine Subaru ever made and you may want to consider this especially if your dumping money and time into it with megasquirt/spark management systems.

 

You could run a turbo on that engine without a brain, but might need to put a carburetor on it. Its a bunch of work thats not worth it IMHO.

 

Josh

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Turbo or not, you don't want water getting sucked in the intake.

 

What made you choose the EA82 platform over the EJ? IIRC the 1.8l NA EJ18 makes more power than the 1.8l turbo EA82T and the EJ18 is incredibly more reliable. When doing an EJ18 swap the entire engine harness comes out as one piece and all you have to do is splice into two connectors. The weight and size difference isn't much, they're just engineered better.

 

I don't think a lot of people will argue that the ea82t is the worst engine Subaru ever made and you may want to consider this especially if your dumping money and time into it with megasquirt/spark management systems.

 

You could run a turbo on that engine without a brain, but might need to put a carburetor on it. Its a bunch of work thats not worth it IMHO.

 

Josh

 

 The EA-82 is the power plant called for in the hovercraft plans, the original power plant was an air cooled  VW flat four.  It's also the engine I aquired to execute the hovercraft build. Not being all that Suburu saavy at the time I might have opted for the other engine.  While some will argue that th EA-82T is the worst engine Subaru ever made, millions of cars ran on them.

IMHO it's like anything else. A company can manufacture 100 million widgets and all you will ever hear about is the 100,000 that broke. Thats a 0.001% failure rate....

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Turbo or not, you don't want water getting sucked in the intake.

 

What made you choose the EA82 platform over the EJ? IIRC the 1.8l NA EJ18 makes more power than the 1.8l turbo EA82T and the EJ18 is incredibly more reliable. When doing an EJ18 swap the entire engine harness comes out as one piece and all you have to do is splice into two connectors. The weight and size difference isn't much, they're just engineered better.

 

I don't think a lot of people will argue that the ea82t is the worst engine Subaru ever made and you may want to consider this especially if your dumping money and time into it with megasquirt/spark management systems.

 

You could run a turbo on that engine without a brain, but might need to put a carburetor on it. Its a bunch of work thats not worth it IMHO.

 

Josh

 

 The EA-82 is the power plant called for in the hovercraft plans, the original power plant was an air cooled  VW flat four.  It's also the engine I aquired to execute the hovercraft build. Not being all that Suburu saavy at the time I might have opted for the other engine.  While some will argue that th EA-82T is the worst engine Subaru ever made, millions of cars ran on them.

IMHO it's like anything else. A company can manufacture 100 million widgets and all you will ever hear about is the 100,000 that broke. Thats a 0.001% failure rate....

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You

 

What made you choose the EA82 platform over the EJ? IIRC the 1.8l NA EJ18 makes more power than the 1.8l turbo EA82T and the EJ18 is incredibly more reliable.

 

EJ18 makes a little less HP than the EA82t. (108 for EJ18, 115 for EA82t *USDM) And weighs about 50lbs more.  I agree about reliabilty but in this case he's got the EA82t

 

I would say that Megasquirt should be able to run it fine....

 

But if you like...you can drop in regular carb or MPFI pistons and run it with no turbo to make about 90~95 hp using all the original Intake minus turbo.

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  • 4 weeks later...

i have had a bit to do with hovercraft.....with a turbo to stop water getting into the intake just take the intake pipe back to just in front of the prop, about 4 inches gap works......with the pipe pointed along the airflow into the prop any water flying past has to make a 180 deg turn to get sucked into the intake.....the speed at which the water is being sucked into the prop means it can't turn fast enough to get into the intake.....and the turbo will compensate for the lower pre-turbo air pressure caused by the prop "vacuum".

 

this doesn't work with a NA intake as the low air pressure in front of the prop niks off with a fair bit of your horsepower

Edited by LPGsuperchargedBrumby
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