I have them all the time..

 

I've never taken apart an ea71 motor. Would the crankshaft fit in a ea82 block? Effectively destroking from 67 to 60mm? Would never do this, but my ADHD won't let me forget the idea. I searched like crazy but all I can find is vague info regarding a prototype motor (dubbed ea72)?!?

 

Edit: typos fixed

Edited March 26, 201412 yr by Ibreakstuff

... I've never taken apart an ea72 motor...

 

Yes, Because the EA72 was a Prototype Engine.

 

http://en.wikipedia.org/wiki/Subaru_EA_engine#EA-72_Concept_Engine

 

Basically talking: An EA71 with the same Lousy Timing Belt Setup from the EA82. I Bet you intend to write EA71, isn't it?

 

Kind Regards.

Yes, Because the EA72 was a Prototype Engine.

 

http://en.wikipedia.org/wiki/Subaru_EA_engine#EA-72_Concept_Engine

 

Basically talking: An EA71 with the same Lousy Timing Belt Setup from the EA82. I Bet you intend to write EA71, isn't it?

 

Kind Regards.

 

Typos fixed. You always get me with those lol.

 

But yea, same lousy timing belt setup.. I guess there would be no benefits haha. I know the muscle car guess love the long rod/destroker setups, it makes up for poorly flowing heads (relative).

Anyone have anymore info about the ea72? I would like to know more about that ugly duckling.

stroker ea71 is probably a smarter idea

EA82 crank in EA71 How about that ? No idea does it work and so on but would be cool to stroke EA71 engine.

EA71/81 cranks MIGHT be swappable between blocks......

 

But Neither will fit in an EA82.....there is nowehere for the disty drive gear to go.....it's right were the #1 main would be.

 

They all share teh same bore size.

 

So.........an EA81 IS ALREADY a Stroker EA71.......

 

So you could say an EA71 is a DESTROKED ea81....

 

And the EA81 and 82 share the same bore and stroke......only HP difference is in the heads and the cams.

 

If you really think Destroking an EA82 would be a good idea............try driving a Sube with an EA71.....you'll get the idea what that combo would be like.

My head hurts. Thanks for clearing that up Gloyale. It was never an actual plan just a harebrained idea lol, I should have realized that the disty location is obviously different crank vs cam driven.

 

It is pretty common to destroke ej257's, they rev to the moon (~9k rpms) and hold a longer power band.. even with the reduction in displacement. It weird the new EE/FA motors have completely square bore:stroke.

 

I'll have to keep an eye out for a PnP ea71/ea81 to teardown and get more familar with. Thats how I first dabbled with ea82's lol, why buy it when you can tinker with it for free on the yard.

While you can rev up the EA engines that high there is no power to found up there.The heads stop flowing around 4-4.5k.Doesn't change the fact that I loved to rev my old EA81s with weber carbs up to 8 grand.No power up there but it was fun to scare people on the sidewalk. 8 grand on an EA81 had people diving off the sidewalk for cover.LOL. 

While you can rev up the EA engines that high there is no power to found up there.The heads stop flowing around 4-4.5k.Doesn't change the fact that I loved to rev my old EA81s with weber carbs up to 8 grand.No power up there but it was fun to scare people on the sidewalk. 8 grand on an EA81 had people diving off the sidewalk for cover.LOL. 

 

You can make the ea82t heads flow pretty well with 2 bar of boost!   Until something pops.

 

8k rpm on any EA motor should sound like the most pissed off can of marbles ever.

My spfi swapped ea81 that I had in my brat would turn 8k, but man it sounded like things were going to start going everywhere lol. But it never did.

... I loved to rev my old EA81s with weber carbs up to 8 grand.No power up there but it was fun to scare people on the sidewalk. ...

 

LoL! ... ...

 

I do something similar with my Weberized EA82, at Higher RPM's it really sounds like it will pump a piston thru the exhaust pipe in no time ... and the Weber yell is Really Loud; but I've years redlining that beast like that, and seems like the EA82 actually Likes to be used at High RPM's.

 

Kind Regards.

My spfi swapped ea81 that I had in my brat would turn 8k, but man it sounded like things were going to start going everywhere lol. But it never did.

How exactly do you get the SPFI to spin that fast? Its fuel map ends at 6500 or there abouts.

You can make the ea82t heads flow pretty well with 2 bar of boost!   Until something pops.

 

8k rpm on any EA motor should sound like the most pissed off can of marbles ever.

They certainly don't sound like the worlds most pissed off can of bumblebees.

 

How exactly do you get the SPFI to spin that fast? Its fuel map ends at 6500 or there abouts.

Not sure about that. Even in the stock application on an ea82 it'll turn 7400 which is valve float. No clue though, it just did. My friend who did the swap was a subaru mechanic and we always got a kick out of it. No power at that level but it took it!

The short stroke should allow all EA's to spin like crazy. But trying it without the required oil pressure...   

Theoretically how fast do you guys think an ea82t could spin with upgraded springs and properly lashed HLA -> solid lifter conversion?

Edited March 26, 201412 yr by Ibreakstuff

Would de-stroking the engine reduce compression or displacement or both? I've read that engines with lower compression are good candidates for forced induction. 

 

John

Would de-stroking the engine reduce compression or displacement or both? I've read that engines with lower compression are good candidates for forced induction. 

 

John

 

With a 92mm bore, 60mm stroke would be ~1595cc and 67mm stroke would be 1781cc. The compression ratio would most definitely change if you tried to use the same rods/pistons, as well as other negative factors. The compression height difference has to be made up in rod length or with pistons (pin height) to achieve the same CR with stroker/destroker, or bad things can/will happen.

 

And lower CR does help with forced induction, otherwise they will knock and shatter pistons/blow ringlands. You can run higher CR with FI if you can keep the detonation in check (racegas, e85, water/meth injection, proper EGT management, etc).

Not sure about that. Even in the stock application on an ea82 it'll turn 7400 which is valve float. No clue though, it just did. My friend who did the swap was a subaru mechanic and we always got a kick out of it. No power at that level but it took it!

ive run several ea82s to 7200 rpm shifts......itll do it. for awhile

what they basically did was to make a belt driven soch version of the ea71 just like they did with the ea81 engine.

I like how the common consensus here is that we all know damn well that the ea motors make more noise than power at anything above 5k, but we've all had them above there. Well above. The 3.9 dual range will get the car to 42 mph in 1st gear. ;-)

 

I like how the common consensus here is that we all know damn well that the ea motors make more noise than power at anything above 5k, but we've all had them above there. Well above. The 3.9 dual range will get the car to 42 mph in 1st gear. ;-)

i guess because were all curious.. i've taken mine well above 8,000rpm (8,500-9,000, not sure since it stops at 8,000) and theres a bunch of nothing to find up there, pointless after 4,500ish on my EA-82 motor. just wanted to know how high i could get it but it scared me before ever reaching whatever i was trying to acomplish, loud little motor..

Edited July 2, 201510 yr by Subasaurus

My CCR EA82T with ported out stock turbo and stage 2 cams makes plenty of power up til 6.5-7k rpm... oh yeah, and 10psi boost with higher than premium gas(: the 2.5" straight pipe makes it sound like a performance V8 after 5k rpm lol

For those of us that don't have $5K in our engines,they run out of hp at a low rpm due to poor flowing heads.

... don't have $5K in our engines...

 

Holy Cow! ...  ... maybe that is much more than the whole car's cost.

 

With that Budget, I rather prefer to swap an electric motor instead...

 

 

Some examples here: ~► http://www.ev-propulsion.com/aboutus.html

 

This is more expensive: ~► http://www.electricsubaru.com/

 

Subaru 360 Electric: ~► http://cleantechnica.com/2012/01/20/subaru-360-revived-as-battery-electric-car-for-the-cuteness/

 

Kind Regards.