legacycentral bbs

I'm trying something here, my 2.2 block is knocking pretty bad at the crankshaft, since it has over 250000km and runs at 10-12psi all day.

So, the cheapest repair i could fine is swapping a wrx block in place of the old 2.2. I neither have the time or money to rebuild a 2.2 block.

I'll either trick my maf signal to lower the injector duty cycle or run 12-14psi boost with intercooler, fcd, and stock fuel mapping. I'll let you know how it turns out.

You shouldn't have to trick the ECU or at least not much. It gets the signal from the MAF and injects fuel for that amount of air. Seems like it would run no problem.

Yeah, you're right. But still, the injector will give an amount calculated for a 2.2, so i'll run a bit rich i guess?

go for it,

id use a 20g instead of a 205 though

That's not how mass-flow engine management works.

This smaller-displacement engine will consume less air, so the airflow meter will measure less air, so the ECU will inject less fuel.

Running rich would be fine, wouldn't it? Other than the mileage, you'd have the ability to up the boost and not have to worry as much about knock/detonation, right?

I really thought i would get a rich mixture too, that's why i wanted too run higher boost. But i might just wait to verify.

But that also mean that the injector won't be working has hard has before for the same boost level at x rpm, since less air is compressed.

I'm i right? i don't want to be optimistic and blow something up

Keep in mind, it will run richer everywhere. Many guys running bigger injectors on stock EM have big problems with super rich idle, the car stalling frequently and fouling plugs really quickly. If you use the EJ22T injectors, it is a non-issue. But if you run the EJ20 injectors, you will need to address this...

What are you going to do with your ej22t block. I would hope that it gets rebuilt. That is the most wanted subbie block out there.

For the block, im trying to spend less money on this car, so i'll try to sell it, it is still good, the knocking is not at a point of no return.

Somebody with more cash coudl build a really awesome engine with that.

To come back on the topic, I wonder what the compression ratio would be, ej20t block with ej22t sohc heads.

I know that a ej22T block with wrx heads gives a lower, 7,3 comp ratio.

Anyone have a clue?

Yep,
If you search this forum, you can find the details on the one I built. A phase I Ej20G block w/Ej22T heads runs a 9:1 CR.

I would need to re-run the numbers for the Ej205 block. The EJ205 block had 8:1 CR stock and 47cc combustion chambers. The Ej20G was 8.5:1 but it's heads had a 57cc combustion chamber. Your EJ22T heads have a 40cc combustion chamber. My gut says you will be right around 8.5:1, but only math would verify that...

The project started today, in 6hrs i have the engine out and ripped apart. Everything on the block swaps over easily.

The only part that bothers me is the head gasket thickness, mine were 0.60 on the 2.2, and the wrx ones are 0.20 thick

I'll double the gasket each side, but i won't triple, it's just to much IMO.

Anyway, 8.5 CR would be perfect to me. I'll keep you guys informed.

when i was using some CR calculator programs i was amazed at the effect the thicknes of the headgasket had on the CR.

I replied to your PM, but we used the EJ22T head gaskets on our build. The small difference in bore shouldn't adversely affect anything...

Or you could always source some EJ20G head gaskets. There are a few sets floating around the country at speed shops and dealerships...

The mechanic i work with wouldn't put bigger bore gasket on the engine, he implied it would generate detonation, 100% sure.

He builds many race engine for rally, and i think the same way he does.

I just dont want to bend a valve because of 0.20 less clearance.

That's interesting. Many of the local guys running Ej22's with Ej25 heads use the EJ25 head gasket to keep the compression up. I have never heard of detonation being an issue on those engines. But then, I am by no means a race mechanic...

It's ALIVE

Took 9hrs from getting the car in to doing road tests. No valve clearance issues whatsoever, i used two 0.20 wrx head gaskets each side.

The CR doesn't seem too high, but thats only butt feeling. It pulls hard, at 9psi for now. The powerband moved higher in the rev range by at least 500rpm. Idle is perfect, not too rich. And i didn't hear any detonation, but i ran 94octane just in case.

Bottom line, it's cheaper and easy to replace an old and tired 2.2t block with a WRX 2.0t block, everything fits except the belt tensioner. DO IT

I calculated the CR of my ej22t head with ej205 block setup.

With 0.40 " head gasket it gives 8:3 CR Just perfect with the small turbo i have. Thats why it pulls so hard at 8psi

Awesome to hear that it's working so well.