Skip to content
View in the app

A better way to browse. Learn more.

Ultimate Subaru Message Board

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.

EA81 performance build essay *HI-RES PIC WARNING*

Featured Replies

Well folks, for those that dont know... its time to come clean with what Ive been doing all winter.

 

Can we say performance build?

 

HERE WE GO :

 

Original EA81 out of my BRAT... YUCK!

 

picture.php?albumid=136&pictureid=1134

 

Tearin' it down...

picture.php?albumid=136&pictureid=1132

 

More teardown...

picture.php?albumid=136&pictureid=1133

 

Now for the hand-cleaning/POR15-ing of the steel parts. :rolleyes:

picture.php?albumid=136&pictureid=1137

 

Case halves off to the machine shop...

 

...while I round up some EA82 SPFI pistons.

picture.php?albumid=136&pictureid=1127

 

:grin:

 

Heads back from Jerry DeMoss... decked .030, ported and polished with a match-port intake. :headbang:

picture.php?albumid=136&pictureid=1121

 

picture.php?albumid=136&pictureid=1129

 

picture.php?albumid=136&pictureid=1128

 

Crankshaft machined 10/10 with new ACL main and rod bearings.

picture.php?albumid=136&pictureid=1122

 

Case halves are back!

picture.php?albumid=136&pictureid=1124

 

 

Camshaft is back, with a DeltaCam torque-grind!

picture.php?albumid=136&pictureid=1126

 

Reassembly.

picture.php?albumid=136&pictureid=1123

 

Case halves back together.

picture.php?albumid=136&pictureid=1131

 

Install pistons. *Note the clearance, this is TDC*

picture.php?albumid=136&pictureid=1136

 

Heads on! Installing rockers and pushrods.

picture.php?albumid=136&pictureid=1135

 

Wheel 'er from the shed to the barn...

(sweet, the engine gets to go wheeling before the brat!)

 

picture.php?albumid=136&pictureid=1125

 

 

Up in the air... install oil pump and filter, fill with oil... and drop er in. :headbang:

picture.php?albumid=136&pictureid=1130

 

MAJOR thanks to Jerry DeMoss and Ken at DeltaCam for the help and great service!

More pics to come... stay tuned.

Edited by backwoodsboy

What kind of carburetor are you going to run, or is it going to be SPFI? Exhaust? Can't wait for a report on it's performance.

  • Author

Currently Im going with the 'ol Weber 32/36 DFAV, which is doing a fine job.

 

Ive actually had it running for 3 days now. Put almost 300 miles on yesterday. :headbang:

 

Exhaust is 2 & 1/4" from the factory Y pipe cat(less) back. :rolleyes:

 

From 1700 - 3000 rpm there is a DEFINITE heavy power band where there previously was, um... nothing.

 

Its a torque-y little sucker, lemme tell ya.

Edited by backwoodsboy

Congrats John!! Will be nice seeing that Brat again. So when are you going to take this POS coupe off my hands?? :) ( seems all my cars go to John)

  • Author
So when are you going to take this POS coupe off my hands?? :)

 

 

Thanks Connie!

 

Jess and I have been talking about doing a hatch as the next project, actually.

 

You dont want that Coupe going to my garage.

 

Id throw in an EJ22T, the XT6 5spd AWD with diff lock, 5 lug swap it, and lower it.

 

Sounds great you say? ....well, then youd be getting it BACK! Dont make me do it. :grin:

Ha the way I feel about that coupe ....it could be sitting out in your field up on its side just like Rocky. And once its gone..I dont even want to see it again....unless it is in the shape of a small cube.

 

So you planning on running the Brat over foofy haired Datsun lady this year?

Edited by Bucky92

pics no worky for me :( stupid mac

 

BTW john let me know how big of a difference you feel in that cam swap. Im thinking i might do that later this summer when i go to redo my valve seals.

Edited by hatchsub

Awesome!! My Brat had shaved heads like that before I bought it, it had somewhere around 120 horse just from that!!! I wanted to do it but I just haven't. I bet there is a big difference. Nice job!! I want some more pics of your Brat!!

I found myself covering up the laptop from the wife. Felt like I was looking at porn with her in the same room as me. I want to see a video of that thing running.

Nice pictures man. Thanks for the nice words on the heads I did up for you. Glad you like them.

 

Now lets see the pretty engine get muddy!:brow:

That's a nice build! I love it someone does the neccessary modifications to make an engine more efficient rather than writing it off because it's not the most powerful engine of the the line. Being a swap junkie I wouldn't know anything about that, but it's nice all the same. :lol:

Yea i think i may go this route too but not sure when ill have the time to do it. I would love a bit more kick with this car.

nice to see an EA81 getting a rebuild and not swapped out for another subaru motor. are the EA82 pistons the same size as the EA81's or did you have to get the engine bored out a bit? what was the cost of the rebuild if you dont mind me asking? my engine went bang today (think it broke a connecting rod) so now im looking at the cost of a rebuild or swapping the engine if my one has too much internal damage.

 

James

are the EA82 pistons the same size as the EA81's
same - interchangeable.

ah yes, very nice, good work man, i admire your skills,nice clean parts, love it!

 

i am thinking of doing the same with mine, but have you had any trouble with skimming the heads? i.e valve timing and all that, as i only get one chance with mine if i do it, theres no go out and get some more!

 

i am going to rebuilding mine soon when the funds come together, ive got a power cam, dualport heads and all that, which i want to transfer over, and ive got a pair of 40 IDF webbers on there way as well very soon as well as wanting to use the 12.5:1 compression pistons avalible from ramengines, what do you reakon power wise and torque yours is now good for, 130hp? 160lbs?

 

im aiming for around 170 hp and whatever torque that produes with it, should be fun, especially in RWD! hahaha

nice jod ya me to what was the cost of the rebuild if you dont mind me asking? I need to know so I can start hooking for extra $$$ or sumthing I love the look of that clean motor mine has so much oil on it it is as big as a V8

  • 2 weeks later...

Looks like a great build.With the Delta cam in it,how's the fuel mileage on it now?That's something I've always been curious about before trying it.

  • 2 weeks later...

Inspiring, truly inspiring. Makes it look possibly for joe shmoe to accomplish... I am tossing around the ideas of rebuilding my EA81 or being all trendy and going with the EJ22 like most people. Thanks for the write up.

  • 9 months later...

Engine looks fantastic. What did your fuel mileage turn out to be? I just bought a 1981 Brat and believe it or not, it;'s actually in good shape. I'm not sure exactly what I'm going to do with it yet, but I do know I want to do what you did to the engine. I have located a car with a SPFI EA82 that I am going to comvert the SPFI unit over onto mine. After reading your performance build I guess I can use the pistons also. Did you use the original rods with the EA81? What did you have done to the case halves? I would like every detail of your build so I can do it. Also, do you think I should leave the stock 4 spd tranny in mine, or should I go with the 5 spd?

  • 3 years later...

Same here - getting this error message : "Invalid Conversion ID"

Ciao, Bantum ...

  • 11 months later...

Please fix the pictures, i could really use it. Thanks!

Please sign in to comment

You will be able to leave a comment after signing in

Sign In Now

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.