1990-1996 Legacy/Impreza AT vs MT Heads difference

[vwilson]

I have a 1996 Impreza MT EJ22. I don't have the car, just the engine. I am looking at converting it to dual port exhaust but have a few questions about it:

1. Will any heads from 1990-1995 be a direct bolt on?

2. I know early cars didn't have EGR but Is there any difference between heads from a AT vs MT car that would prevent me form using AT heads?

3. I think my current engine has Roller Rockers and HLA. What do most 1990-1995 heads have and should I swap these over during the conversion?

4. Would EJ22T heads work or should I stay away from those for my purposes? Is it easy enough to block off the oil ports on the passenger head for non-turbo applications?

Any help would be much appreciated.

 

Thanks.

Edited September 16, 2019 by vwilson

[wtdash]

1. Yes

2. No difference except for that EGR port, that can be blocked off.

3. I can never remember the name - Tappets?- and HLA on '90-'95. I don't know if those are worth swapping or not.

4. Yes, the block is the same in '96, just the single-port, RR + HLA, differences.  I put EJ22T heads on an extra '90 or '91 engine, with the '96 Intake manifold, ran NA for  few months before going turbo'd -LINK. I was able to block the water and oil ports off w/out an issue...but don't recall what I used, but I had a bunch of left-over parts, bolts, etc, so probably just used what I had.

 

Good luck w/the 'vanagon' (?) project? :-)

 

Edited September 16, 2019 by wtdash

[vwilson]

Awesome thanks for this. 

It’s actually a ‘66 Split bus conversion.

It’s amazing how well these engine fit in that engine compartment.

For the Turbo heads did you just use the plate on the back of the NA head? I’m new to these so I have no idea if this is the right block off for a turbo or even where the passageways are on the turbo heads.

Edited September 16, 2019 by vwilson

[Hellzbellz1234]

bro that things gonna be scary fast

[FerGloyale]

Any Dual port EJ22E heads would work. 

They all use that same plate......it blocks the distributor port.  No USDM cars got distributors though so they all have plates here.  EJ18/22

Turbo heads have like m10 and m12 or 14 banjo bolts for coolant and oil lines......easy to block off.  Hardest thing is the return tube, it's got to be extracted (kinda tough) or cut and shut (welded closed).  Or if you want to be hoopty just put a capoff over it's end.......it'll get oily though.  But why unless you just have them lying around?  They are Slide Follower/Hydro adjuster and same size valves so nothing gained to use for NA.

USDM options are basically 90-94 with Slide follower/Hydro adjuster or 95 which IIRC are Roller follower/Hydro adjuster. Between those 2 options I'd go with the 95.  95 from AT will need EGR port plugged, easy.  m16 bolt IIRC?  or just take a old EGR tube end and cut and shut.

 

I personally would try to find some JDM EJ20E (NA) heads.  Same size valves and combustion, but with non-interfernce, Roller follower/Solid adjuster cams and rockers.

Those are the Heads and Cams I run on my lifted wheeler.  Weighs ~3500 lbs and pushes 31" tires.  I did de-burr and "match" the heads to the intake ports and de-burred and light polished the exhaust ports.  Well worth the work if you are gonna have the valves pulled for a grind already.

And yes that will be crazy scary fast.  What trans are you using?  The stock one will be WAAAY short geared for that EJ.  You'll be shifting every 0.5 seconds! And it might break it.....I'd be careful with 130 hp through a box built for about 50.  Lucky for you there are lots of options for upgraded VW trans and adapters.  

 

[vwilson]

This is great information. Thanks. I don't have EJJT heads I've been offered to buy some but didn't know anything about them. I'd prefer to not use them. I kind of thought that '95 heads would be slightly better for what I'm doing. The problem is they are impossible to find. 

I'm currently running a Rancho, Prostreet, Freeway Flyer transmission so it should handle the extra HP. Also put front and rear disc brakes.

Well I guess I'll have to call a ton of junk yards to find some '95 heads.

[el_freddo]

I’d love a set of the EJ22t heads and an ECU if I could source one - but postage over the puddle to here would be a killer  

I have some EJ20 Na heads here but I’m unsure of their condition. It wouldn’t be hard to get another set. But again, the postage stateside would be more killer than from there to here. 

Sounds like a cool build! 

Cheers 

Bennie

[Numbchux]

'96 EJ22 is going to be single exhaust port. Everything '90-'95 will have dual ports. So your exhaust manifold will have to change to match.

22t heads would be the same, but the cams will be cut different for the turbo application. You'd want to get N/A cams from the same year (I don't know the details on this, but when I had Delta grind some cams for me years ago, there were at least a couple different versions in those years).

 

5 hours ago, el_freddo said:

I’d love a set of the EJ22t heads and an ECU if I could source one - but postage over the puddle to here would be a killer  

No you don't....Those heads and ECU are good for nothing more than stock power (and stock EJ22t power is nothing to brag about).

[wtdash]

47 minutes ago, Numbchux said:

 

 

No you don't....Those heads and ECU are good for nothing more than stock power (and stock EJ22t power is nothing to brag about).

I respect your opinion, and would state w/a 'chipped' EJ20G ECU those heads don't produce HP,  but torque is notable.

This is w/the following upgrades, but all on the stock engine:

Setup:
Stock EJ22T and heads
TMIC
"550" STI injectors (525cc)
TD05H (with 90 degree inlet from '93-'96 wrx/STI)
Exhaust: 3" downpipe and  all the way back w/Dynomax muffler
STI Fuel Pump
Rob Tune EJ20G ecu and ignition converter
JECS "green label" MAF
Snorkus removed
 Mopar (Neon, etc.) coil pack and newer-style EJ22 wires.
Stock BRK6E plugs gapped to .028

--MBC set to ~18.5 psi; pull done in 4th gear.

 

Remember This is at the WHEELS, not the crank.

Run 1
HP: 229 HP
Torque: 309 ft-lbs

Run 2
HP: 219 HP
Torque: 287 ft-lbs

 

 

 

 

Note: I apologize for the thread hijack.

Edited September 18, 2019 by wtdash

[el_freddo]

20 hours ago, Numbchux said:

No you don't....Those heads and ECU are good for nothing more than stock power (and stock EJ22t power is nothing to brag about).

For what I want to do they’ll fit my needs. Plus there will be factory data on the emissions side of things that’ll help with my engineering requirements. 

The turbo oil and coolant feeds on the back of the head would be a bonus too - makes things a pot load easier to plumb things in! 

Cheers 

Bennie

[Numbchux]

2 hours ago, el_freddo said:

For what I want to do they’ll fit my needs. Plus there will be factory data on the emissions side of things that’ll help with my engineering requirements. 

The turbo oil and coolant feeds on the back of the head would be a bonus too - makes things a pot load easier to plumb things in! 

Cheers 

Bennie

You have much better options available to you. Plumbing oil and coolant lines isn't difficult. You could pay a machine shop to modify heads to add the ports for a tiny fraction of the cost of the shipping from here (not to mention it can be DIY'd with half decent tools).

 

22 hours ago, wtdash said:

I respect your opinion, and would state w/a 'chipped' EJ20G ECU those heads don't produce HP,  but torque is notable.

Yea, they can perform, I've probably seen a hundred builds like that, even helped hands-on on one about 15 years ago which had a Link standalone and almost every supporting mod solely to see the limits of the SOHC heads. He swapped to EJ25D DOHC heads (still with N/A Cams) and performed so much better in every way.

Edited September 19, 2019 by Numbchux

[el_freddo]

8 hours ago, Numbchux said:

You have much better options available to you. Plumbing oil and coolant lines isn't difficult. You could pay a machine shop to modify heads to add the ports for a tiny fraction of the cost of the shipping from here (not to mention it can be DIY'd with half decent tools)

Thanks Chux, I can see how to tap oil and coolant from the back of the NA head. I’ll look into this further. 

I know we have better options, that’s why I have a Gen1 RS turbo. The EJ22 turbo build is being built to fit into a space that I don’t want to modify - and I’m not for all our power, just a bit of fun. 

I’ll leave that there, I’ll move on and drop any further inquiries in this thread. 

Cheers 

Bennie