soobme Posted October 19, 2005 Share Posted October 19, 2005 I'm thinking of building a hot EA81. So I need some info. 1) can the EA81 be stroked at all? If so how much? 2) I'm looking for about 10.5:1 CR, what pistons do I need? And can I mill the heads to get it right where I need it? (I'm not sure what to do about pushrods if I mill the heads) 3)What brand/type of rings do U recomend? Quote Link to comment Share on other sites More sharing options...
Bobby_boucher Posted October 19, 2005 Share Posted October 19, 2005 I was also thinking about building up and ea81 but have no idea where to start or what to use. Qman has about 150 hp out of his ea81 he said somthing about building it to air plane engine specifiations. I have no idea where to get the specification for the airplane engine though. Quote Link to comment Share on other sites More sharing options...
NoahDL88 Posted October 19, 2005 Share Posted October 19, 2005 1) I'm sure it could be stroked, but you'd have to find a rod that would work on your own, i don't know anyone thats stroked an EA-81 2) You might try www.ramengines.com they might have custom pistons, you won't be getting 10.5 with any subie pistons 2.5) You can mill the heads up to .030, any more than that and the intake won't fit anymore 3) for rings i'd contact either Ram /\ or Emily at CCR Quote Link to comment Share on other sites More sharing options...
soobme Posted October 19, 2005 Author Share Posted October 19, 2005 I didn't think about the intake:banghead: I plan to make my oun header for it. Any advice on what size tube to use for the header? I would be shooting for power in the 1500-5000RPM range. Quote Link to comment Share on other sites More sharing options...
Snowman Posted October 19, 2005 Share Posted October 19, 2005 EA82 SPFI pistons will get the compression up to 9.5:1. With some milling, you can get more. You should be able to compensate for some milling just by adjusting the valve lash differently. I'd just go with OEM rings from a discount supplier. They don't fail very often, so I think they must be pretty good. Quote Link to comment Share on other sites More sharing options...
mcbrat Posted October 19, 2005 Share Posted October 19, 2005 I'm thinking of building a hot EA81. So I need some info.1) can the EA81 be stroked at all? If so how much? 2) I'm looking for about 10.5:1 CR, what pistons do I need? And can I mill the heads to get it right where I need it? (I'm not sure what to do about pushrods if I mill the heads) 3)What brand/type of rings do U recomend? if you decide to bore, I have a new set of .030 over ea71 pistons with rings. Repco brand. $70 shipped. Quote Link to comment Share on other sites More sharing options...
soobme Posted October 19, 2005 Author Share Posted October 19, 2005 if you decide to bore, I have a new set of .030 over ea71 pistons with rings. Repco brand. $70 shipped. What would the CR be with stock heads? Any one know what the displacment is @ .030 over? Quote Link to comment Share on other sites More sharing options...
soobme Posted October 20, 2005 Author Share Posted October 20, 2005 Any one here played with nitrous yet:brow: I'm thinking a 40-50HP kit would be a kick in the @$$! Also, any one know how much bigger the hydro head valves are than solid lifter heads? Quote Link to comment Share on other sites More sharing options...
TheSubaruJunkie Posted October 20, 2005 Share Posted October 20, 2005 Tony... ive dreamt of building a monster EA81. Same lines your runnin.... 10.5:1 CR, cams, pistons, intake... etc. But I also wanted to run EA81T heads that have the injector bosses for the MPFI. Forget about carburation, and then say hello to N.O.S!! -Brian 1 Quote Link to comment Share on other sites More sharing options...
soobme Posted October 20, 2005 Author Share Posted October 20, 2005 I would LOVE to get my hands on the manifold I have seen here that is for the single side draft webber. That's what I would like to run, but I think I'm gona end up with a little 390cfm Holley 4bbl. Quote Link to comment Share on other sites More sharing options...
mcbrat Posted October 20, 2005 Share Posted October 20, 2005 I would LOVE to get my hands on the manifold I have seen here that is for the single side draft webber. That's what I would like to run, but I think I'm gona end up with a little 390cfm Holley 4bbl. 390 should work good. I just pulled a 600 of my 82 Brat. it was a blast, but I need to keep the revs high.... http://www.ultimatesubaru.org/80s/mick/gallery/holley1.jpg http://www.ultimatesubaru.org/80s/mick/gallery/holley2.jpg http://www.ultimatesubaru.org/80s/mick/gallery/holley3.jpg http://www.ultimatesubaru.org/80s/mick/gallery/holley4.jpg http://www.ultimatesubaru.org/80s/mick/gallery/holley5.jpg Quote Link to comment Share on other sites More sharing options...
soobme Posted October 20, 2005 Author Share Posted October 20, 2005 That looks good, what manifold & adaptors wer U using? Quote Link to comment Share on other sites More sharing options...
mcbrat Posted October 22, 2005 Share Posted October 22, 2005 That looks good, what manifold & adaptors wer U using? I used the following weber adapter 2 weber 1/2" spacers standard 2->4 barrel adapter that I used a cone grinder to "widen" the 2 bbl holes inward to match the weber patter which is a bit smaller. it's much nicer to drive around town now with a weber on it. Quote Link to comment Share on other sites More sharing options...
antimarx Posted May 5, 2013 Share Posted May 5, 2013 Can an EA 81 be re-sleeved for 101 mm bore? Quote Link to comment Share on other sites More sharing options...
Gloyale Posted May 5, 2013 Share Posted May 5, 2013 Can an EA 81 be re-sleeved for 101 mm bore? I don't think so. the "sleeves" are cast into the blcok, and they aren't very thick. Quote Link to comment Share on other sites More sharing options...
Crazyeights Posted May 6, 2013 Share Posted May 6, 2013 (edited) Tony... ive dreamt of building a monster EA81. Same lines your runnin.... 10.5:1 CR, cams, pistons, intake... etc. But I also wanted to run EA81T heads that have the injector bosses for the MPFI. Forget about carburation, and then say hello to N.O.S!! -Brian Standard EA81 heads can be drilled and fitted with injector bosses if you want to run multi-port. This way you don't have to hunt down the almost impossible to find EA81T heads. Most machine shops should be able to do it. If you run in to trouble, RAM Engines can do it for you. Edited May 6, 2013 by Crazyeights Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.