18e heads/22e block obd1 hybrid

[pleaidestar]

I want to do a non traditional build for my 1st gen wagon, I THINK theoretically and mechanically its possible..but I'm no hp engine builder nor know the boxer motor well. I have gotten a little bit of info about changeover parts and some specifics of both motors

Correct me if I'm wrong on these parts:
18e heads, valve train and cams are more aggressive, can be used safely on 22e block to raise compression.
18e I/m, same bolt pattern will bolt to 22e heads alike, and possibly flows better than 22e manifold.

The outcome I'm hoping for if all the parts can work together is a high compression motor, I don't mind torque dropping off a little bit in low end of the rpm range (since its going to happen anyway), I would like to hit a redline of 6800-7000, the 22e block is strong enough that is no question..I just want a few brains to pick at since I am inexperienced in boxer motors...

any input is welcome, if I'm ridiculous I don't mind hearing it either. Danka.

[pleaidestar]

Reason for my thinking about this kind of hybrid is that the cam profile on the ej18e is different than the ej22e and maybe the only difference..I'm not sure about the rest of the valve train. I originally wanted to send my spare cams out to delta but then thought if I can get a little higher compression and more agressive cam grind maybe the car would respond better and be a bit quicker than it is now..respectively I'm not looking to drag this car off the street, I want better pull through the gears when I want/need it.

[pleaidestar]

Ok...does anybody know the valve differences of the two heads, clearance, length etc....I may just have to pull it apart and do the measuring and math and figure it out myself then?

[GTDrifter]

My cousins running 18 dual port heads on his 22e, its a high compression engine then

[pleaidestar]

Do you by chance know the compression ratio, or if he had to play with the air/fuel ratio? I really want to do this but I don't want to chase my tail for things I don't know, just wondering if I should run 18e cams in the 22e heads. But do t know if the valve springs will take the pressure of the bigger lobes.

[GTDrifter]

I'm pretty sure he just swapped the heads and exhaust manifold drove. I think it was 9:1 but I'll ask him

[pleaidestar]

Cool thanks Gt.

In the back of my mind I thought it could just be a quick swap, and work well I think the non-interference type motors would give you more room to work with, I want to get the valves as close as possible. Thought about some Cometic ultra thin h'gs to get them closer even, will be playing with fire though. I'm sure it helps that both those motors are non-interference.

[pleaidestar]

I got those 18e heads a couple days ago for 80 bucks, not too bad looking I guess, no apparent misfiring or headgasket leaks on the car. Maybe I lucked out, and maybe this will work and be happy. Going to start disassembling them in a few days, any tips or advice as I have never done this kind of work before and a bit gun-shy about this.

[pleaidestar]

Well...I scrapped the hybrid build with the 18e heads, had the heads tanked and find out there is some micro cracking on the cam journals from oil starvation apparently. Come to find out by measuring the 18e heads valves are a lot smaller than the 22e. So I have bad heads to try my luck and get a feel of a slight PnP.

Sent an inquiry to delta cams this morning on my 22e cams based on a torque grind, and a mild pnp. I may be required to find valves with smaller stems and possibly upgraded valve springs but all of these I'm unsure of until I reassemble the heads and measure the open springs. I have little experience with these motors and would glad if anyone had any input or knowledge with these kinds of mods. I got some conflicting info on polishing the intake ports on the heads, not real familiar with the product of polished ports but am familiar with doing the work as a machinist and fabricator.

What I'm hoping to to hear is that a lower to mid range torque grind and a polish for upper rpm flow will give me a quickly revving motor. What you guys think?

[pleaidestar]

Amazing, can I get a link err something. I have done all the searching I could and only come up with what I'm getting here.

[86bratman]

I've never seen any evidence that says they ej18 heads have a different combustion chamber than the ej22. All I've read for the last 10+ years is speculation, "well its a smaller motor its heads gotta make my bigger motor have higher compression"

If you have both sets of heads off and available could you take the time to cc each head's combustion chamber and put an end to the guessing?

[pleaidestar]

The chamber is the same size but the valves are smaller, as far as I know the 22e valves are the largest of all ej motors...speculation probably because this is the only Subaru I have ever had. The hybrid build is shitted on because I'm not going to buy new 18e heads, these that I have will cost a lot to build and hone. So I'm trying to pull better flow out of 22e dual port heads since apparently 18e heads flow badly too accompanied by teeenie valves.