Now thta I work at a Subaru only repair place here in VT, we have lotsa long and short blocks hanging around. One of the techs and I want to build a snotty motor.

We just got a 96 brighton with the 1.8 in it.... I was thinking of building the phase I 2.5 short block with my 2.2l single port heads for me... what would the 1.8l heads on the phase I 2.5l block do? is that dangerous CR?

we have access to anything USDM for combos...

where would I find a chart for CCs of the different blocks and heads?

he wants to do something fun with the 1.8 without much work (read engine mgmt or terbo swap, staying NA) and so do I

We live in an OBDII state, so we have to stay legal....

the bore of the Ej25 is too great to put Ej18 heads on it, and you would be upwards of 13:1 CR anyways. I don't know of any formal chart. We tried to get a FAQ together at one point, but I don't have a clue to the title of the thread. I think the best resource is the "high comression frankenstein" thread over in the NA forum...

I dont think a hybrid motor would pass obdII.

Sorry, but you're not going to get much out of that 1.8 unless you go with some sort of forced induction. If you want to stay NA, the 2.5/2.2 combo yields good results. As far as the OBD-II stuff goes, you'll be fine. The only issue could be the 1.8 EGR plumbing. I was able to remove this from my car completely & still have it pass, but mine's a 93.

Sorry, but you're not going to get much out of that 1.8 unless you go with some sort of forced induction. If you want to stay NA, the 2.5/2.2 combo yields good results. As far as the OBD-II stuff goes, you'll be fine. The only issue could be the 1.8 EGR plumbing. I was able to remove this from my car completely & still have it pass, but mine's a 93.

There's the kicker. With a '96, if they plugged it in to the OBD scanner, it would probably throw a code for the EGR being disconnected. There's a reason I bought a '95 and not a '96...;)

the brighton has an EGR? my 96 wagon doesnt! (2.2l)

Some information here that might help you - http://wac.addr.com/auto/obs/turbo/ejcalcs.html .

Pat

Some information here that might help you - http://wac.addr.com/auto/obs/turbo/ejcalcs.html .

Pat
thats mostly info about turbo setups though.

yeah... I wish it had the one we are talking about.

thats mostly info about turbo setups though.
:confused: There's data listed for 8 different Subaru engines, only two of which are turbo. All of the data in that table is for USDM cars, the majority of which (when that table was originally created) are N/A.

The data for the '96 EJ18 is there. The head volume hasn't been directly measured by Wayne (hence the TBD in that block), but you should be able to calculate it based on the information that is there and the advertised compression ratio. You have the CR, and you have all but one of the variables that determine CR - solve for the one missing variable. (And people always complained about having to take that math crap in school! :lol: )

Once you have that you can calculate the CR for the EJ18 head/EJ25 block combo. If you don't know how to do those calculations, then I would submit that you probably shouldn't be mismatching heads and blocks.

Pat

PS - I get 12.0:1. And that still doesn't address the issue that Matt Monson raised, namely that the bores on the EJ25 are too big for an EJ18 head.

:confused: There's data listed for 8 different Subaru engines, only two of which are turbo. All of the data in that table is for USDM cars, the majority of which (when that table was originally created) are N/A.


hes looking for info on hybrid n/a motors, which that list doesnt have. Thats all I was getting at

I would suggest going with a Phase II 2.5 shortblock and a set of 2.2 heads that will work with your 1.8 manifold. im pretty sure there are certain years that are swappable. That would eliminate wiring. I would also suggest going with the thickest head gasket you can find, since the 1.8 doesnt have a knock sensor running high compression is probably a bad idea. A thick phase I gasket will bring you close to stock compression, but you will be gaining the displacement and the flow over the 1.8

OBDII is the devil. its a PITA to make pass.
if you look. about 75% of the swaps are OBDI

the bore of the Ej25 is too great to put Ej18 heads on itNot to mention the fact that the valves/ports are so small they won't fill the cylinders past the midrange. You'd have really nice low/midrange torque and then it would fall flat on it's face.

Well the frenkenstein (98 EJ25 DOHC block / thick HG / DUAL port SOHC 2.2l heads) is together and running... he says "frank" feels like a "snotty" impreza RS. Its in his 96 brighton... Now that our junkyard el-cheapo toy is together, im really itchin to do a junkyard / used parts turbo build up...

I found some used EJ22T heads on ebay for cheap... along with the pistons... which im thinking I wont use if an Idea I just had seems more plausable...

what do we all think:

98 EJ25 (DOHC phase I) block with the EJ22T heads.. I am not understanding the CR chard well enough posted above to figure out the CR to find out if this is boost friendly...

would this be plausable, or would my original plan of putting the EJ22T pistons into a EJ22 (NA) block be a better idear?

again, this will all be accomplished with a used X-member, turbo manifold, turbo, injectors, piggyback EM, TMIC, exhaust...

I just wish the IAC was on the OTHER side of the intake manifold for our cars... would make this easier...

I might have a set of 22t heads in a week that you can have. Needs cams though. 2.5 block with 2.2 heads is going to give you high compression, not something you want for boost. turbo pistons in n/a block would work, or 2.2t heads with 1.8 block also.

what would the 1.8l block do for me? would that be beneficial at all? less displacment will have what benefits?

1.8 block with 2.2 heads will give you the low compression you want for turbo. Plus the 1.8 is known to take some serious abuse.

wouldnt I get the same with a 2.2l block with the turbo pistons (which I just won)?

what benefits would the 1.8l stock block have over the 2.2l block with the turbo pistons?

wouldnt I get the same with a 2.2l block with the turbo pistons (which I just won)?

what benefits would the 1.8l stock block have over the 2.2l block with the turbo pistons?The EJ18 has thicker (way thicker) cylinder walls than the EJ22E, but unless you aiming for a really high boost setup that won't be of any help. I'd go with the EJ22E block and EJ22T pistons with either EJ22E or EJ25 heads. The EJ22T heads are too restrictive to make serious power.

not looking for SERIOUS power....

like I said before, just a junkyard build!

use the 2.2 bock with turbo pistons. 2.2 turbo heads will make it easier becuase they already have oil feed, return and coolant return on them. They arent any more restrictive that 2.2 n/a heads. the intake valves are 1/16" smaller, and the ports are the same size.

To do it right, you are going to want to crack open the Ej22e, pull out the internals and hone the cylinders, before installing the Ej22T pistons (along with new rings). In my mind, that's a lot of work for a junkyard build, unless you want to do it for fun.

Personally, I would use the Ej18 bottom end with the Ej22T heads and call it done. It's so much less work, and you will be pleasantly surprised by a low CR Ej18 with 10-12psi of boost...

thats what im looking to do matt...

just a nice side project. hmm the 1.8 bottom end needs no re-pistoning???? with the EJ22T heads, whats the CR?

I do think we have a few of those hanging around, and I can always resell these pistons.

oh and BTW, regular EJ22 HGs? or anything different?

http://www.vincentfurniture.com/subachad/

i was just thinking about this. i bought a 93 L with the ej18, and i have a ej22t that i was going to use in place of the ej18 shortblock. i have heads from the ej20g (actually we arent sure which ej20 they are from, they look different than the ones i sold) and i was thinking of using those heads on the ej18. that would make it real boost friendly i believe. i wasnt going to be running it on a lot of boost anyway. what do you think of that set up? will that ej18 shortblock be able to handle lets say, 12 PSI of boost from a TD-04? my junkyard ej22t may need a rebuild, and i dont have enough money/time/know-how to do that as of right now.

Do it. And run 15-16psi. You will have a super low CR and the Ej18 can take the boost...

why the subachad up and downpipe? wrx ones dont work?

i was just thinking about this. i bought a 93 L with the ej18, and i have a ej22t that i was going to use in place of the ej18 shortblock. i have heads from the ej20g (actually we arent sure which ej20 they are from, they look different than the ones i sold) and i was thinking of using those heads on the ej18. that would make it real boost friendly i believe. i wasnt going to be running it on a lot of boost anyway. what do you think of that set up? will that ej18 shortblock be able to handle lets say, 12 PSI of boost from a TD-04? my junkyard ej22t may need a rebuild, and i dont have enough money/time/know-how to do that as of right now.

Well, I will be doing the EJ18/22T heads im convinced... now I will have a set of EJ22T pistons for sale!

the great thing is that people give 1.8 shortblocks away for free.

you guys say that the ej18 can handle that boost?? that sounds great, it'll probably just be temporary tho, unless i really like it! :-) anyone know the exact CR for that combo? would be around 8:1? or even lower? which head gasket would i use? ej18?

why the subachad up and downpipe? wrx ones dont work?

IIRC, subachad's uppipe is made to go around the crossmember, so you dont have to get a turbo crossmember. the downpipe, i dunno why that would be needed. a wrx one should work.

the downpipe, i dunno why that would be needed.Because Subachad's uppipe does not put the turbo in the same place as the WRX...

tzedek: I haven't seen direct comparison numbers between the EJ22E and EJ22E heads, and in any case they wouldn't mean much if they weren't taken on the same bench. I do remember reading some threads where an EJ22T user had gotten good gains swapping to the n/a heads though. 1/16" on the valve diameter is not insignificant.

http://www.vincentfurniture.com/subachad/


www.uniquemotorsports.com

:) It's back.

I thought it was determined ej18 and ej22 heads had the same volume, thus no change in CR?

that is what i thought too. that would be why you would need like ej20g heads for that. they are huge! hopefully the passages line up pretty well.


redwagon, thanks for clearing that up/downpipe question up. ive never seen subachad's up/downpipe in person. but i have a turbo crossmember anyway, so ill just use that! ;)

If I was doing another build, I would use a n/a 2.2 liter block and an ej25 top end. I would transfer the throttle body and wiring from whatever the stock motor is, ej18 or ej22. I would then use the stock ecu, upgrade the injectors to either 370cc legacy or wrx injectors depending on the year of intake manifold and use an e-manage again to handle fuel, timing, and voltage clamping if it's a map based car. Even on a MAF, I was hitting 4.85v which is pretty close to maxing out the MAF.

Chad

Well, with the exception of the head block combo, thats what im doing.

22T heads, 18 block, e-manage, 3xx nissan injectors, RRFPR, and run it....

stock exhaust to start and make it run, then start on the upgrades... first to build the motor!

im hoping to find a good EJ18 block at work or locally...

aren't early ej18 blocks(pre late 94-early95's) built with sti parts just not as refined?

but i've heard 2.2e has thicker sleeves previously?

what would be more durable as a frankenbuild with mild boost?

ej18+ej22e/t heads w/thick HG?

or ej22e bottom+2.5 heads and thick HG? bore out 1.8(2.0) with 2.5 heads maybe thick HG??

obviously the displacement comes into play, but CR's should be boost friendly enough on either to warrant 10-15psi.

i too have 1.8 and 2.2 stuff layin around and would like to build something for S&G!

and if the 1.8 has thick enough sleeves can't you bore it out a bit(2.0) and run 2.5 heads and stock HG for boost? or even thick HG for sick potential(being limited by probably by heads, bottom end, fuel system at that point)?

just curious, and heard different info on the 1.8 vs 2.2 blocks that i wanted to get straight before going further. it may help others now as well as in the future.

cheers!

--keith

I have a set of 22t heads if anyone is interested. as well as a bunch of other 22t stuff, manifold, down pipe, turbo. cant remember what else, but more.

I might want the downpipe

aren't early ej18 blocks(pre late 94-early95's) built with sti parts just not as refined?

but i've heard 2.2e has thicker sleeves previously?

what would be more durable as a frankenbuild with mild boost?

ej18+ej22e/t heads w/thick HG?

or ej22e bottom+2.5 heads and thick HG? bore out 1.8(2.0) with 2.5 heads maybe thick HG??

obviously the displacement comes into play, but CR's should be boost friendly enough on either to warrant 10-15psi.

i too have 1.8 and 2.2 stuff layin around and would like to build something for S&G!

and if the 1.8 has thick enough sleeves can't you bore it out a bit(2.0) and run 2.5 heads and stock HG for boost? or even thick HG for sick potential(being limited by probably by heads, bottom end, fuel system at that point)?

just curious, and heard different info on the 1.8 vs 2.2 blocks that i wanted to get straight before going further. it may help others now as well as in the future.

cheers!

--keith


i believe if you want a boost friendly car, you should go with the 2.2 with 2.5 heads. that is a good combo becuz the 2.5 heads have big volume.

i dont think the 1.8 would benefit anything from the ej22e/t heads at all, unless someone actually has done the numbers or has made one before. it just sounds like it would have the same C/R. but if you were to use ej20 DOHC heads, that would lower the compression and make it boost friendly.

i dont think the 1.8 would benefit anything from the ej22e/t heads at all, unless someone actually has done the numbers or has made one before.

The Ej22E heads have bigger valves and ports, so they could support more flow. Also, I am not convinced that the Ej18 heads have the same size combustion chamber. Who determined this and how? I just fail to see how a head with a smaller bore would have the same volume, even if the dome height was the same. I may just need to measure a set for my own knowledge...

Im wondering what the CR would be, or is this a wild goose chase....

if you have 1.8 heads and 2.2 heads, why dont you fill both combustion chambers with oil and see how much it takes to fill them up? If it's the same with both, then there is our answer. If the 2.2 takes more to fill, then it obviously has a larger volume and therefore 2.2 heads on a 1.8 = lower compression.

Seems better than guessing to me :confused:

yea, i posted what "i had heard" and that's why i said someone should try it out and tell us! would make things a lot easier. i dont have a 1.8 or 2.2 head out and about so i cant do that.

Seems better than guessing to me :confused:

To me too. That's why I was asking who had actually determined that they were the same. ;) I've got Ej22E, Ej22T and Ej18 heads sitting around, but very little interest in measuring them at this point. I've got way to many projects going on in my garage right now and don't even have the bench space to pull them off the shelf for measuring. Maybe somewhere down the road, I will find the time, space and motivation.

Diz's running an Ej18-T these days, and his mad scientist gears have been spinning. He'll probably manage to get me to do some fact finding on his behalf at some point. But don't hold your collective breaths. I leave for Berlin in 2 days and you won't see me online for a few weeks...

Using the numbers on ejcalcs, and some math I calculated the ej18 head volume to be aprox 32cc, a lot lower than ej22's 40cc. Now Im not claiming this is perfectly correct, and also I dont know if the pistons protude from the block at TDC. If all other variables are equal and the pistons do protude, the combustion chambers would have to be bigger to get back to advertised 9.5:1 stock compression ratio. Also ej18 and ej22s share the same stroke, as such there the entire difference is made up by bore. Just my guess.