Report on ej20 sohc combo

mhrallyteam · Post by **mhrallyteam** » Tue May 10, 2005 5:14 am

Just to give some feedback on my ej22T with ej20T block, or let's say ej20T sohc. Im utterly satisfied, i feared losing power or torque, but thus far it is an impressive engine. Not 350hp STI impressive, but more pretty damn close to a wrx at 12 psi impressive.

For the cost this is a great alternative. The 8:25 CR with 11psi and 4:111 gear ratio gives a solid performance in every gear. I wanted to share my joy, i love my car again.

THAWA · Post by **THAWA** » Tue May 10, 2005 6:17 am

I was contemplating doing this not too long ago. Glad to hear it's worth it. How does it compare to the stock setup? Or did you have the stock setup?

Project_Legacy · Post by **Project_Legacy** » Wed May 11, 2005 12:33 am

yea i'd like to know as well. im pretty sure i am going to do this hybrid in the next few weeks. could you tell us which parts you used? such as what from the ej22t and what from the ej20t? or was it pretty much JUST the shortblock of the ej20t? also, did you have to buy a new gasket set for the ej20t or did you use ej22t gasket set? thanks for any info you can provide. i'd be greatly appreciated. i really want to get this car up and running SOON!!

thanks again

mhrallyteam · Post by **mhrallyteam** » Wed May 11, 2005 5:39 am

all you need is a ej20t shortblock and 2.0l head gasket, that's it

Compared to the stock setup :

The powerband went up in the tach range by 500-750 rpm, it pulls strong until 6000rpm

It revs much easier, i think the piston coating has a lot to do with this

The turbo doesn't seem to be out of puff as soon as before, but it comes at 2750-3000rpm instead of 2250-2500

At 9 psi it pulls more then at 11psi with the old block

I now use a wrx oil pump and water pump, the oil press is 25psi higher at every rpm.

At the price the wrx shortblock was its defenitively worth it

Project_Legacy · Post by **Project_Legacy** » Wed May 11, 2005 2:19 pm

heheh. nice man. thanks a lot.

Matt Monson · Post by **Matt Monson** » Wed May 11, 2005 5:16 pm

Just for clarity he is using an EJ205 USDM WRX shortblock. If you use an EJ20G JDM shortblock, your results will be similar, but your CR will be 9:1

Project_Legacy · Post by **Project_Legacy** » Thu May 12, 2005 1:34 am

o damn thats not good. how could i make it have lower CR without changing pistons? thinner head gaskets? if i do that i run the risk of maybe the valves hitting the piston. i was told that motor im lookin at is an interference motor. any suggestions guys? thanks

Don

THAWA · Post by **THAWA** » Thu May 12, 2005 2:12 am

I believe it's only a valve to valve interference motor in stock form.

evolutionmovement · Post by **evolutionmovement** » Thu May 12, 2005 3:08 am

Thinner gaskets would raise the CR anyway.

Steve

Matt Monson · Post by **Matt Monson** » Thu May 12, 2005 3:55 pm

9:1 is still pretty boost friendly as long as you have decent engine management to govern it. The pistons on the EJ20G stick out of the deck even a touch more than the EJ22T does, so I would not recommend a thinner gasket. You might rin the risk of the piston actually hitting the lower edge of the combustion chamber on the heads, and not just the valves. To find out for sure, you would need to take some measurements.

I do know a buy in LV (Subachad on other boards) who built one of these engines recently with the EJ20G. He wanted to drop the CR a bit more, so he actually ground out some material from his EJ22 cylinder head to give it more volume. He did this with the valves out as he was rebuilding the heads with a full port job. You could say he blueprinted his heads. I don't know how much he gained, but probably enough to drop it a .1 or .2 in CR. He is running the car at 10psi on a TD04 (almost identical to the VF-10 in flow) with no problems. He plans on upping the boost to 12 or so overtime.

The trick with running a higher CR on a turbo is you don't boost them as much. Your effective CR is higher because your base CR is higher, and thus boost should be a bit lower to avoid detonation...

Impregacy · Post by **Impregacy** » Thu May 12, 2005 6:03 pm

is the bore size of the ej20g smaller than that of the ej22's? If so, are the chambers on the ej22 heads a little big. Also do the pistons seem to match the head in terms of the quench pads? Subaru engines are a bit of a mystery to me because of their tendancy to detonate even with low low compression. Someone on theoldone.com said it was in part because of the comustion chamber design and in part because of the cam timing. So i guess i'm just wondering if the ej20g block and pistons are a better match for that head.

Project_Legacy · Post by **Project_Legacy** » Thu May 12, 2005 9:07 pm

im sure the ej20g bore size is smaller than the ej22t. i dunno about the combustion chamber stuff tho. i was told i should use the ej20g head gasket for this project. i dunno... im going to check out the motors in a lil bit. thanks guys. hey matt were u using the ej20g?

Matt Monson · Post by **Matt Monson** » Fri May 13, 2005 12:31 am

Head volume on the Ej22T (and E) heads is 40cc
Head volume on the EJ20G is the largest Subaru ever used at 57cc

Bore is smaller on the 2.0. And the pistons are essentially flat tops. But who told you that Subaru's are prone to detonation? That's a load of hooey...

We used an EJ20G on our build. It is non-intercooled currently and detonates above 10psi at anything over 4500rpm. Timing control and an intercooler will address that eventually. Keep in mind, we are using a 1.8l ECU, which advances timing more than either of the 2.2l ECU's...

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Report on ej20 sohc combo

Report on ej20 sohc combo