cal_look_zero Posted March 1, 2012 Share Posted March 1, 2012 I've finally pulled the trigger on getting everything situated to build my frankenmotor. I decided to rebuild one of my ej25d blocks; start from split cases and end up with hopefully around 185hp/180tq for under $1000. Here's the build list as of now: EJ25D core engine - $75 Cometic H1631SPK040S hybrid head gaskets - $100 ACL 5M8297 Main Bearings - $45 ACL 4B8320 Rod Bearings - $28 GT NPR 12033 AA760 STD Piston Rings - $68 Delta 1000 grind cams - $180 Singleport SLA/RR 2.2 heads with port match. $50 (So I can work with them while not having to tear my engine down. Grimmspeed 8mm Phenolic spacers. - $80 Gaskets - $100 Machine Shop Labor - $100 ______________________________________________________ Basically, I found out from a rather potent frankenmotor build on SLI, that Cometic makes an ej22 head to ej25d/1 block head gasket that optimizes coolant flow. I'm purchasing my rings, bearings, and head gaskets through Built Industries, and I HIGHLY recommend dealing with them. I imagine that I'll have more to add as I go, but thus far I'm stoked to get the project rolling and hopefully install the engine sometime before my birthday in May. Luckily, my timing set is brand new, my clutch is brand new, and I can do all of the work outside of decking the block and heads by myself. I'll be keeping a detailed log of my progress as I go and taking lots of pictures to aid in anyone else's endeavors into this territory. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted March 2, 2012 Share Posted March 2, 2012 Any particular reason you went with Single port heads rather than dual port? Are they phase 1 or 2? (probably a stupid question, don't think phase 2 heads ever come single port) Seems to me I remember reading about improved port flow characteristics of the phase2 heads, but you give up some small amount of compression due to a larger combustion chamber. Quote Link to comment Share on other sites More sharing options...
cal_look_zero Posted March 2, 2012 Author Share Posted March 2, 2012 Any particular reason you went with Single port heads rather than dual port? Are they phase 1 or 2? (probably a stupid question, don't think phase 2 heads ever come single port)Seems to me I remember reading about improved port flow characteristics of the phase2 heads, but you give up some small amount of compression due to a larger combustion chamber. I already built a header and am starting with a singleport setup anyways. I was debating going dp phase 1, but eh... Quote Link to comment Share on other sites More sharing options...
987687 Posted March 2, 2012 Share Posted March 2, 2012 Any particular reason you went with Single port heads rather than dual port? Are they phase 1 or 2? (probably a stupid question, don't think phase 2 heads ever come single port)Seems to me I remember reading about improved port flow characteristics of the phase2 heads, but you give up some small amount of compression due to a larger combustion chamber. Phase2 2.2 heads are single port, 2.5 are dual. That's awesome you posted up all the part numbers and prices on the major ej25d rebuild parts! I've been looking for a while and never found stuff that cheap, or really knew what to buy. It would be interesting to have the single port 2.2 heads and the dual port 2.2 heads flow tested on the bench. I'm not really convinced the dual ports flow better, they go to the same size exhaust pipe anyway. It's a much bigger exhaust port than the dual port ones, it's probably close to the same surface area. Quote Link to comment Share on other sites More sharing options...
ShawnW Posted March 3, 2012 Share Posted March 3, 2012 I agree on the exhaust. Its a matter of simple math, as well as "why would Subaru" logics. I also like that there is one less stud to deal with as these do tend to pull threads, rust nuts to studs, etc. Quote Link to comment Share on other sites More sharing options...
cal_look_zero Posted March 3, 2012 Author Share Posted March 3, 2012 Being that I'm port matching the intake and the exhaust, I should see a much better flow out of the singleports. Standard dual port primaries are only 1 3/8" into 1 5/8" secondaries; whereas I'm up to 2" on mine, and planning on a 2 1/4" secondary and piping to the muffler. Quote Link to comment Share on other sites More sharing options...
cal_look_zero Posted March 14, 2012 Author Share Posted March 14, 2012 I refer you to the carnage thread: http://www.ultimatesubaru.org/forum/showthread.php?t=131215 Basically I thought I was going to get 2 rebuildable engines, turns out I got 1 usable block out of the whole deal (aside from the parts I'm going to sell) However, some light at the end of that tunnel. I took my carnage rods and cranks to my usual machine shop to see if anything was salvagable. He took the parts in on trade towards a reground crank and set of rods. With all the bearings and piston rings, I spent $270 and will have a virtually new rotating assembly. So the build is back on the road. My (hopefully) good block is currently being hot tanked and honed, and I should be assembling my "new" shortblock this weekend. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted March 14, 2012 Share Posted March 14, 2012 The whole deal about the cometic gaskets and "optimized" coolant flow is just smoke and mirrors. The FM hasn't got any trouble cooling itself using untrimmed Subaru OEM gaskets. The whole point of this build is that it's cheap - can't do much in the way of special parts without ruining the price/performance ratio. Though I suppose if the cost isn't too much higher than OEM then it probably isn't going to hurt anything either. GD Quote Link to comment Share on other sites More sharing options...
cal_look_zero Posted March 14, 2012 Author Share Posted March 14, 2012 The whole deal about the cometic gaskets and "optimized" coolant flow is just smoke and mirrors. The FM hasn't got any trouble cooling itself using untrimmed Subaru OEM gaskets. The whole point of this build is that it's cheap - can't do much in the way of special parts without ruining the price/performance ratio. Though I suppose if the cost isn't too much higher than OEM then it probably isn't going to hurt anything either. GD Barely $10 more than OEM and I'm getting them .010 thinner than OEM for that extra little bump in CR. Quote Link to comment Share on other sites More sharing options...
cal_look_zero Posted March 15, 2012 Author Share Posted March 15, 2012 Looking forward to assembling this tomorrow. Quote Link to comment Share on other sites More sharing options...
Ricearu Posted March 16, 2012 Share Posted March 16, 2012 too close and those pistons will contact the heads. how far do the pistons clear the block by? Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted March 16, 2012 Share Posted March 16, 2012 (edited) Assemble the block and measure it, that's the only way to know for sure. Better do that before you order your head gaskets. You might need that extra .01". Edited March 16, 2012 by Fairtax4me Quote Link to comment Share on other sites More sharing options...
cal_look_zero Posted March 17, 2012 Author Share Posted March 17, 2012 The machinist didn't want to screw with decking the block, so the HG is the only point I'll be shaving any depth. I almost have the block built, just waiting on enough time to commit to it. Not taking other builds as gospel, but the one I'm following closest had his block shaved 010 and ran 020 under HGs, so I doubt I'll have an issue. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted March 17, 2012 Share Posted March 17, 2012 For best HG adhesion you *should* deck the block. If your machinist can't do that - you need to find another machinist. Mine rebuilds Subaru engines just about ever day. He decks 100% of the 25D blocks he does. He says he's had problems prior to this policy. GD Quote Link to comment Share on other sites More sharing options...
cal_look_zero Posted March 18, 2012 Author Share Posted March 18, 2012 For best HG adhesion you *should* deck the block. If your machinist can't do that - you need to find another machinist. Mine rebuilds Subaru engines just about ever day. He decks 100% of the 25D blocks he does. He says he's had problems prior to this policy. GD There's a difference between "can't" and determined it to be unnecessary since the block was probably done within 500 miles of the engine going. Yes, all of the signs pointed to a bonehead rebuild and subsequent failure of the engine. Properly reassembling/resealing the oil pump was a procedure the PO should have followed a little closer. Anyways! All ready to get assembled when my parts start coming in the next week or so. These engines are surprisingly simple to build from scratch. Then again, the last time I split cases, I was 17 and rebuilding a VW 1600. Quote Link to comment Share on other sites More sharing options...
cal_look_zero Posted April 2, 2012 Author Share Posted April 2, 2012 Headgaskets should be here tomorrow. Then I can get to final assembly and then hurry up and wait for the weekend after Easter to install it. Quote Link to comment Share on other sites More sharing options...
doc526 Posted April 2, 2012 Share Posted April 2, 2012 Looks good. Quote Link to comment Share on other sites More sharing options...
NorthCoast Posted April 9, 2012 Share Posted April 9, 2012 Quote Link to comment Share on other sites More sharing options...
samneric Posted April 9, 2012 Share Posted April 9, 2012 here too What did you use to paint it? Quote Link to comment Share on other sites More sharing options...
ivans imports Posted April 9, 2012 Share Posted April 9, 2012 I modifyed a stock 2.5 headgasket to acomadate the 2.2 heads had to drill 13 holes in very specific spots but will work fine i agree with gd cometic headgasket is smoke and miriors the block and head surface is ten times more inportant than the headgasket fancy headgaskets whont take up clearance any better than stock one. All the blocks i plane have low barrels by a cupple thow the planer misses the top of barrel first two- three passes i think the blocks get warped and damaged more than anyone thinks Quote Link to comment Share on other sites More sharing options...
cal_look_zero Posted April 9, 2012 Author Share Posted April 9, 2012 here too What did you use to paint it? Duplicolor engine enamel. I actually started with BBQ paint but it was way too flat and would have soaked up oil, so I went with the enamel. Left the oil pan in BBQ paint though. I don't believe that having a less efficient cooling system is "smoke and mirrors" but to each their own. If I'm going to pay nearly $100 for factory head gaskets that don't quite line up, I may as well pay another $14 for ones that align the water jackets and don't give the engine any more reason to run warm. In any case, it's going in this weekend. Long block is all assembled, just need to put the timing belt on, adjust the valves, and try to find my timing covers... Quote Link to comment Share on other sites More sharing options...
Recian Posted April 10, 2012 Share Posted April 10, 2012 im kind of curious to see how this works out. I've got the chance to snag a EJ25 from a late 90s outback for cheap and i was intending to do this to it and drop in my impreza. The black block looks pretty sweet tho Quote Link to comment Share on other sites More sharing options...
NorthCoast Posted April 10, 2012 Share Posted April 10, 2012 im kind of curious to see how this works out. I've got the chance to snag a EJ25 from a late 90s outback for cheap and i was intending to do this to it and drop in my impreza. The black block looks pretty sweet tho You and me both. I picked up an EJ25 short block from a 98 OB for $90 and I have a set of 2.2 heads from a 91 Legacy. I'm hoping I can just slap it together and drop it in without doing a complete rebuild. Quote Link to comment Share on other sites More sharing options...
ivans imports Posted April 10, 2012 Share Posted April 10, 2012 the best 2.5 is the 95-96 with big pistons the aluminum is cast like the 2.2 b bitt different quality of casting and the biger pistons are not as prone to slap Quote Link to comment Share on other sites More sharing options...
Recian Posted April 10, 2012 Share Posted April 10, 2012 the 2.5 i saw was in a 98 legacy outback wagon.. i think. It had a V vin. I got my front bumper from a impreza outback wagon and it had a 2.5. It was the same body as my impreza so 94-98 era. The legacy block will cost me $50 since it's $50 at the yard for everything you can carry out and i can carry a bare block. the impreza 2.5 will cost me about $200 since it's classified as an engine. so the real question is there any other identification other than the EJ25 stamp on the block to isolate the 2? Quote Link to comment Share on other sites More sharing options...
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