ej18 power improvements?

[tallwelder81]

where can i get some lighter, lower-friction, high-compression ej18 pistons?

 

everytime i search google for "ej18 performance" or whatever, i get a ton of links, i open the links, and CAREFULLY read the pages, but they always seem to be for parts that fit an ej22.

 

any info on what folks on here have done with their ej18s? portmatching? compression?

intake work?

headers?

balancing?

i am on a tight budget. but as time goes by, i can come up with funds to

have machinework done.

is there any reality behind my theory that BORING the ej18 cylinders bigger would add power, AND lighten it up, based on my impression that the block casting walls are relatively thick and heavy?

[Mykeys Toy]

I believe you are having a hard time with that specifically because aside from cams it is more cost effective to do a 2.2 or frankenmotor swap. You can get the dual port headers in several places but ebay is the cheapest then add cams. I would call someplace like RPM Rons or go to the website They seem to be able to get anything you need at least for the engines I have looked at.

 

Mike

[WoodsWagon]

Is there a reason why you need to run the EJ18 block? Class restrictions for racing?

 

An EJ18 block bored out and resleeved would be the same thing as an EJ22 block. Bore it out some more and put a stroker crank in it, and you have a 2.5l block.

 

There's really no reason to put any money into an EJ18 when there's better factory options out there. Plus they bolt right in.

[idosubaru]

what they said. block boring/rebuilds are very expensive so the obvious answer to your question, since finances are a factor - is to just get an EJ22 or EJ25 and bolt it in. there's nothing to it, it's really easy.

 

i removed an EJ25 from mine and installed an EJ18, you'd just do the opposite, very easy. though i'd stick with an EJ22, much better motor and the swap is less work since your EJ18 intake manifold bolts right to an EJ22. manifold doesn't bolt to an EJ25 so you'll have to swap wiring harnesses, or get creative. not hard but a good bit extra work where the EJ22 is bolt up....and far more reliable...and much cheaper. they're a dime a dozen compared to EJ25's.

[bheinen74]

out of ALL the junkyards i go to, Evey single one with a ej25 in it has printed on the window, bad engine.

 

 

Every single one with ej22 in it has printed, engine good....

 

that means something if you are looking for reliability.

ej25 is not as reliable. proven over and over

 

if you want to stick with ej18, get delta cams, and be done.

[tallwelder81]

thanks everyone. i do not race professionally, no class restrictions.

i wanted to stick with same size as stock, i just wanted a newer engine.

i already have the ej18 and i dont have a ton of cash left over after buying it.

NOT that i got ripped off on the deal, he treated me good and its a very fair price i paid for the engine.

 

gas mileage is a major priority for me. for 20mpg, i wouldnt even drive a brat.

my stock ea81 was probably.... 28mpg. the ej18, i am expecting... maybe around 30 or 32 mpg.

 

i guess i will just do the delta torque cam, and then hopefully some port work on the intake, exhaust and the chambers/throats.

 

where do you guys all go to get 3 angle valve-grinds on ej engines?

i just want a nice valve job, and a cam, and i suppose i will be happy.

 

any input on who does good and reasonable priced port work in the seattle/tacoma/everett area?

[idosubaru]

oh and many EJ22 and EJ18 parts are interchangeable, so you might see a lot of EJ22 commentary since that's the more common engine when talking about parts, etc. like lightweight pulleys for instance if you were looking into those - same part.

[Gloyale]

 

An EJ18 block bored out and resleeved would be the same thing as an EJ22 block. Bore it out some more and put a stroker crank in it, and you have a 2.5l block.

 

This is not really true. Or possible.

 

 

EJ 18 bore = 87mm

 

EJ22 bore = 96.9mm

 

Nearly 10mm larger

 

Subaru specs for bore enlargment.= 0.5mm

 

 

 

These are not cast V8s. there is not any material to "bore out to ejxx"

 

You can fit a .25 or .50 over piston for a rebuild but that's it.

 

 

The cylinder in an EJ engine is like a big open topped barrel inside the block. While the outside walls, and bearing castings of all the EJ engines are the same, the "barrels" that make the cylinders are physically different for each respective piston size. Both in inside(bore diameter) and outer diameter.

 

You cannot bore an EJ18 to be an EJ22. The outer diameter of the barrel of an EJ18 is nearly the diameter of the EJ22 piston you want to put in it. The iron sleeve of the EJ18 is much smaller than the EJ22 piston.

 

IF you were to attempt to bore out an EJ18 to 22 you would end up with aluminum cylinder walls about 1-2 mm thick. Not to mention you'd need to bore even bigger to fit a sleeve. It just isn't possible.

[tallwelder81]

ok fair enough, and thanks for the warning.

 

even if it were possible physically, it sounds expensive.

 

but i read in a well known source that subaru made the ej22

better by a new, low-friction, lighter-weight piston.

10% more power, 3% more fuel efficient.

 

my question then, i suppose, would be:

 

does anything like that exist for an ej18?

new and improved, lightweight, low friction pistons?

[idosubaru]

here are aftermarket pistons:

http://www.importperformanceparts.net/imports/rodpistoncombo_subaru.html

 

you might want to look into rebuild costs - they are rather costly. i got all amped up to rebuild a subaru motor a few years ago then started pricing it all out and it's not cheap at all once you start tearing into the block. i'd price out everything and see what the financial picture actually looks like. headgaskets, resurfacing heads, valve job, delta cams....you're already at the cost of just buying an EJ22 in my neck of the woods. more money, less power.

 

you could also buy a car with a blown motor, install the Ej18, sell it, and then buy an EJ22. or buy a cheap car with a good EJ22 - swap motors and resell it. i could easily end up ahead doing that here, but it's not hard to find rusted out cheap cars that are otherwise in great shape out here.

Edited July 18, 2011 by grossgary

[LeoneTurbo]

I am doing the same to my EJ18E for my EA81 wagon as fuel economy has top priority.

 

I'm fitting EJ16E pistons which up the compression ratio to 10.6 when you're using the early 1992-1996 pistons with long skirts or to 11.0 when using the later low friction light weight EJ16E pistons.

 

The EJ16E and EJ18E run the same heads and block bore, the only difference is the shorter stroke of the EJ16E with longer rods and domed pistons. The piston compression height is identical between EJ16E and EJ18E pistons so they are a direct swap. Piston rings EJ16E and EJ18E are identical.

 

 

 

 

 

That hike in compression ratio will dramatically improve engine efficiency. Together with some torque cams you could improve it by as much as 10-20% while still getting decent torque.

 

I will be running mine with a 2006 and later exhaust manifold which also requires a different oil pan, that should yield even more power and torque.

 

I expect my modified EJ18 to make 125 hp at 5500 rpm and 125 lb-ft at 4500 rpm.

 

I will also fit a modified trasnmission with extra long ratios and a 3.9 final drive. Engine rpm at 60 mph is going to be about 2400 rpm. Not good for overtaking but excellent for smooth and frugal cruising.

Edited July 18, 2011 by LeoneTurbo

[Mykeys Toy]

The higher powered engines came in the mid to late 90s here. They will have IIRC single port exhaust and are interference engines so if or when you lose a timing belt it is time to have the heads and pistons checked.

 

Mike

[LeoneTurbo]

All EJ18E engines are non-interference engines... Check out the deep pockets in the pistons.

[tallwelder81]

Awesome! now thats the kind of solution i was hoping for.

 

some relatively cheap and relatively easy factory parts swap with a solid and noticeable improvement.

 

 

 

but this all brings up a NEW question. where do i get ej16e pistons, and how common are they, or to put it another way, how high should my hopes be of finding them?

 

P.S. thanks leone. big clear pics are always a help. and thanks to everyone else also.

[LeoneTurbo]

They (the 1.6L) have been available in Europe and Japan in the Impreza GC/GF line. So chancing running into them stateside are pretty slim.

 

I ordered them new from the dealer here (in Europe) and they were around 50 euro each excl. tax (which would not be due when shipping outside Europe).

[tallwelder81]

so maybe like 250 US cash? thats not bad.....

 

out of my budget TODAY, but very attainable in the future at some point.

 

wonder what shipping would be.

[cutlass69]

out of ALL the junkyards i go to, Evey single one with a ej25 in it has printed on the window, bad engine.

 

 

Every single one with ej22 in it has printed, engine good....

 

that means something if you are looking for reliability.

ej25 is not as reliable. proven over and over

 

if you want to stick with ej18, get delta cams, and be done.

 

Not completely true the EJ2.5 is reliable as long as you keep the timing belt up to par.

[LeoneTurbo]

Belt issues? Head gasket failure is the biggest reliability issue of the EJ25.

[cutlass69]

but that was just an issue from the type of HG they used right? not the engine it self?

[tallwelder81]

hey, damnit. YOU arent supposed to hijack MY threads.

only i am supposed to do that to everyone else. what the heck???

 

lol.....

[LeoneTurbo]

but that was just an issue from the type of HG they used right? not the engine it self?

At first (with the composite gaskets) it was the gasket, later on with the MLS gaskets it's the block. Due to vibration of the clinders (it's open deck remember) the block rubs against the MLS gasket causing the block to wear. The only fix is to deck the heads AND the block and it will be good for another 100-150k miles.