Yet another head question please

timmy p · Post by **timmy p** » Sat Oct 04, 2008 1:11 am

OK, so I am having a heck of a time finding the EJ20G,H, and K heads, and I dont really want to worry to much about the wireing for the the phase 2 stuff (EJ22T 94 Legacy RS Turbo wagon).

Aside from getting the EJ25D (P1) DOHC heads, what about the NA heads from the EJ22E (NA EJ22)? Dont they have larger intake valves ? In theory they would flow more than right?

If I were to run those (EJ22 NA heads) would the cam gear sensor work? Plus if I got an entire engine it would also come with the correct fuel rails and intake to use the side feed STi injectors as well. Would this be a decent alternative than searching forever to find a set of the EJ 20 *** heads?

my build so far is:
EJ22T block
weisco pistons
TD04/VF39 (Cant decide)
PP6 EM
07 WRX intercooler
coolant tank mod

intake and heads are undecided at this point, please help me out. Apperantly the tuner shop is saying it may cost a fortune to rebuild the stock heads and for a fortune I can get some better ones.

Thanks for any help.

-Tim

timmy p · Post by **timmy p** » Sat Oct 04, 2008 1:47 pm

Anyone ?

dscoobydoo · Post by **dscoobydoo** » Sat Oct 04, 2008 5:49 pm

Sadly, I do not think the na ej22 heads are going to be worth the trouble.

While the G/H/K heads are not easy to find, you have to be patient.

And I would not bother with the TD04. Not much of an upgrade from the Vf-11. ( And it seems you are working every other angle on the build.)

Just keep checking the boards and ebay.

93forestpearl · Post by **93forestpearl** » Sat Oct 04, 2008 11:51 pm

The EJ25D heads have much much larger ports than any EJ22E heads. They can be had for cheap and work really well. The only thing is it is worth the time and money to go to shimless buckets.

On top is a 22T head. Below is a 25D head. They are about a 60 cfm increase in flow. Plus, they are cast as a turbo head and are easy to make work. Oil feed is a plug that's already there, and the bosses for the coolant and oil drain are there, you just have to drill and tap them.

Also, if you are going through all this trouble, don't dink around with a TD04.

dropdfocus · Post by **dropdfocus** » Sun Oct 05, 2008 3:35 am

Agreed, the EJ25D heads are a decent & achieveable option for higher flow heads. As for the VF39, beware of the hot sides getting cracks around the EWG flapper. A very common problem with them. This is the main reason I chose not to go that route and why many STi owners are dumping them on NASIOC left & right.

93forestpearl · Post by **93forestpearl** » Sun Oct 05, 2008 3:54 am

^ True. If you are patient, you can find a VF22, 34, etc for reasonable money. What you define as reasonable money is your call. If you are willing to spend a few duckets and can/learn to weld, you have many more options open to you.

PhyrraM · Post by **PhyrraM** » Sun Oct 05, 2008 3:54 am

Here's an old thread that deals with the mounting locations on the EJ25D heads.

http://bbs.legacycentral.org/viewtopic.php?p=245655

dropdfocus · Post by **dropdfocus** » Sun Oct 05, 2008 4:13 am

Nice, thanks for the link to that older thread. I made sure to save the pictures for later use when spring rolls around & I swap the 22T/25D balanced & blue-printed hybrid motor into my car.

93forestpearl · Post by **93forestpearl** » Sun Oct 05, 2008 5:44 am

Good deal on going with the 25D heads. They actually make the ports on WRX heads look small.

kleinkid · Post by **kleinkid** » Sun Oct 05, 2008 6:44 am

Is there a particular span of model years of the EJ25 DOHC that would be better to use than another?

93forestpearl · Post by **93forestpearl** » Sun Oct 05, 2008 6:55 am

Well, the '96 25D heads used HLA's, which aren't the best for going over the stock redline. On the other hand, the sold shim-over-bucket design of the '97-98 is ok, unless you want to push it. The shims can pop out if you have nasty misfires or use launch control, when then tears everything up.

I trying to chase down some shimless buckets for mine, since everything is the same as the newer WRX stuff. I just don't want to pay $18 for each of 16 buckets.

dscoobydoo · Post by **dscoobydoo** » Sun Oct 05, 2008 5:11 pm

As for the VF-39 crack thread:
While the crack has been an issue on the Vf-39 and some VF-43's, it is more of a visual issue than a performance one.

less than 1% of these cracks actually cause issues in the turbo.

Read up on NASIOC on this. I also have an 05 STI, so I made sure I was knowledgeable on the issue because I HAVE a VF-39.

But due to this problem, it means people panic and dump their turbos for cheap.

i still support using a VF-39 or VF-43.

timmy p · Post by **timmy p** » Wed Oct 08, 2008 2:18 pm

Thanks for the help!!

iluvdrt · Post by **iluvdrt** » Sat Oct 11, 2008 3:18 am

Ok, it seems we (timmy p and me) got the 98 DOHC heads, cams and stuff on order so I have few more questions to installing them.

1. Will the cam gears work off of the p1 dohc with the cam sensor, and if not, how do I fix that?

2.Which HG do we use? I believe the kit Tim bought comes with Cometic HG's for the EJ22T, probably stock thickness. Will these work?

Will EJ22T head bolts work, or are we better off going with studs from ARP? If we need studs which engine do we buy them for, the 22t or the 98 EJ25 (since were using those heads)?

3. As far oil goes(for the turbo), we can tap into the head and braze a fitting into the oil pan for the return right? And the coolant can just be tapped into the heater hoses. I would rather not dump all of that hot oil and coolant into the head if we dont have to. I read the turbo hook up thread above, and dont really like the return spots in the head. (I have been lurking for about 2 months now LOL)

Thanks.

93forestpearl · Post by **93forestpearl** » Sat Oct 11, 2008 5:54 am

1. The triggers are the same. You can use your cam and crank angle sensors from the 22T heads.

2. You can use the stock gasket. Your compression ratio will be a tad low though. Cometic makes a 98mm bore, .051" gasket for the 22T application. It's .008" thinner than stock.

You cannot use the 22T head bolts, as they are about .7" longer. You shouldn't really reuse torque-to-yield bolts anyways. The standard DOHC (WRX, STi, whatever) head studs from ARP work fine.

3. There is a plug on the head you use for an oil source. The spots for coolant are pretty blatant, just drill and thread for a 1/4 NPT. As far as the oil return on the head, its a non-issue. The factory return spot goes right into the main oil return galley, so you are not dumping a bunch of hot oil into the inner workings of the head. If there was a problem with it, Subaru would have done something about it a long long time ago.

If for some reason you still decide to put the return on the pan, make absolutely sure that your return spot is above the level of the oil in the pan, otherwise the oil will back up in the drain, and journal bearing turbos really do not take too kindly to improper drainage. Namely the shaft seals.

dropdfocus · Post by **dropdfocus** » Sat Oct 11, 2008 1:02 pm

All extremely good information to pass along Dan!

iluvdrt · Post by **iluvdrt** » Sat Oct 11, 2008 5:58 pm

Cool, I guess we will just use the head oil/coolant ports since they arent a big issue. It seems safer in the long run.

Our rebuild kit from top line came with weisco head gaskets (Stock ej22t), so well just use them. Compression being a tad low doesnt concern me to much as long as the car will still start and run ok off boost.

ARP bolts here we come. I know on my EJ25D build Subaru reccomended using the stock bolts over again, because the torque to yeild didnt strech the bolt. I have almost 40k on that rebuild with no probs, so I just thought would ask. Thanks.

You guys have been VERY helpfull, we really appreciate the help.

iluvdrt · Post by **iluvdrt** » Sat Oct 11, 2008 8:59 pm

OK it appears the EJ22T intake will not bolt onto the ej25d heads. Which intake manifolds will work with the least amount of wireing problems. I am guessing the EJ25D intake will work, but I am having a heck of a time finding a complete manifold. Are there any other options??

PhyrraM · Post by **PhyrraM** » Sat Oct 11, 2008 9:17 pm

EJ20G is the easiest. It's designed for the 90 degree turbo inlet. And the EJ22T harness will work with very minor mods.

Failing that any phase 1 DOHC intake will work. EJ20K and Legacy twin turbo (EJ20H and R) are factory turbo but designed for the under manifold turbo inlet. EJ25D is common, but has EGR and is a non-turbo design. I bet there is tons of info on turboing the EJ25D on RS25.com

I have a EJ25D manifold I can let go of if you can't find local.

iluvdrt · Post by **iluvdrt** » Sun Oct 12, 2008 3:12 pm

Well, Looking at my intake on my 98 GT aside from the egr the intake looks to be almost identical to the ej22t's as far as IAC valve, and connectors. Plus it will accept the larger injectors from the STi.

As far as EGR goes, its no biggie, Ill just make a block off plate for it.

I am really leaning towards this intake because the ej20 is hard to find parts for, and I am already familar with it.

iluvdrt · Post by **iluvdrt** » Sat Oct 18, 2008 6:33 pm

OK, I got the EJ25d heads from a 98 with the buckets over the valves. Problem is, is they came disassembled and the buckets were just tossed in a box. Does it make a diff where they go? I took a pick and pulled the shims out and miked them. I have 1 that is 2.64mm a few that are 2.51-3 mm and the rest are 2.31-2.35mm. How do I determine where they go?

Also can you buy the fuel rail o-rings, bucket seals, and injector hold downs from the dealer? will the injector hold down caps from the ej22t manifold work on the ej25?

I am also not sure where to drill on the head for the oil retun line(is that the line that needs drilled or is it coolant?). I lloked at the pics posted above in the link, but I am not sure what hole it is I am drilling for.

will the ej25D DOHC rocker type t-belt tensioner work on the ej22T block or do I have to use the t-belt tensioner from the EJ22T with the STi t-belt?

Which spark plugs do you guys reccomend...STi, or EJ22T, or EJ25D?

Also so far here are some parts I just got:
ARP head studs
EJ25d intake manifold
t-belt covers
invidia up pipe
STi exhaust manifold
STi mid pipe
Flowmaster muffler (came with the car 2.75")
STi yellow injectors
STi t-belt
new water pump (NAPA)

Thanks for the help.

iluvdrt · Post by **iluvdrt** » Sat Oct 18, 2008 7:07 pm

Also it looks loike I would be drilling 2 holes in the head is this correct? 1 for the oil return in the lower corner, and 1 for the water return in the unfinished hole by the oil return hole. Is this right? What size bits would I use, and thread pitches for the taps?

Thanks for the help.

iluvdrt · Post by **iluvdrt** » Sun Oct 19, 2008 3:20 pm

Anyone??
I will be installing these things shortly, I really need some help, perhaps a "sponsor" who can help walk me through this. I only have about 1.5 months to finish because I deploy soon, so any help is greatly appreciated.

93forestpearl · Post by **93forestpearl** » Sun Oct 19, 2008 5:58 pm

How about a 1/4 NPT? That should work fine. Or you can go with a larger size if you want.

iluvdrt · Post by **iluvdrt** » Sun Oct 19, 2008 10:53 pm

NPT fort he oil?

As far as coolant, cant that be routed into the heater hose tube? It looks like it would work.

legacycentral bbs

A forum for 89-94 BC-BF(BJ) Legacy Owners and Fans

Yet another head question please

Yet another head question please

model year