Hey im sure i'll get flamed but i searched for about 20-25 minutes and couldnt find this specific instance. now i have to go to work so i'm out of time to look for it.

I have a chance to purchase a JDM Ej207 shortblock (including pumps an pan) to put into my 04 WRX. It has 30k (its on mwsoc) and from what i understand and have been vaguely told is that it would be as simple as dropping in the new block. Theres no wiring or modifications necessary right? Also can someone shed some information on the Ej207 (aka the advantages over my stock block besides stating 'more power holding') such as will i see a power gain?

Sorry if its a dumb question but i'm new to scoobies.

You won't see a power gain unless you have the supporting mods to take advantage of this block. It is stronger because it is semiclosed deck, so it will take more boost without cylinder flex. But if you don't have a turbo that can give that to you and a way to tune it, there's no point...

i have a stock turbo now with all supporting mods for a bigger turbo but dont trust my stock wrx block. For the money would you suggest to just take apart my motor and rebuild it for that? I dont intend going huge but would like an 18g or vf39

You won't see a power gain unless you have the supporting mods to take advantage of this block. It is stronger because it is semiclosed deck, so it will take more boost without cylinder flex. But if you don't have a turbo that can give that to you and a way to tune it, there's no point...

It also has factory forged internals and is balanced. You can safely run a 207 bottom end to 8500 rpms or so.

could my stock heads take an increased rpm range?

The EJ207 has higher compression so you would see power gains and faster spool. What those would be exactly I dont know. You would have to get a tune, head work etc. If you are getting this you may as well get a full longblock or full motor swap. Any motor work on a WRX worth doing is worth doing right. IE: get parts that were specifically made for each other.

would it be worth it to just go for a s2 crawford short block instead?

no

i would wager that most people here are perplexed at the desire to upgrade a 205 block w/ a vf39/18G .. its simply not necessary. that setup is only good for 240-300 whp max.. a tune by a reputable tuner is far more valuable

no

i would wager that most people here are perplexed at the desire to upgrade a 205 block w/ a vf39/18G .. its simply not necessary. that setup is only good for 240-300 whp max.. a tune by a reputable tuner is far more valuable

+2....unless you have a shaddy tune there is no reason your ej205 wont support either of those turbos. Start talking gt-30's and other larger turbos then I'd be conerned. Just make sure you get a good tune and tell the tuner you dont care about peak power but want the car to run for xxxx amount of miles.

im mainly worried about the block crapping out on me. How much would it be after all if i spun a bearing on my stock block

understood
but its more about the tune than the block the 205 is FINE to those power levels
save your $

im mainly worried about the block crapping out on me. How much would it be after all if i spun a bearing on my stock block

If you spun a bearing it would be because your tune was off and you detonated or you contaminated your oil with a fueling issue. Or it would be because you overrevved it. I am with Jaxx on this. Spend your money in other directions.

Americanyouth,
ALL Ej20's have a forged crank and forged rods. Not ALL Ej207's have forged pistons. Some do, and some have hyperuetic cast pistons. I don't assume it's forged unless they confirm the one they are looking at is in fact forged pistons...

Yes all ej20s have forged rods, but only the 207 has rods light enough to handle the rpm.. as for the forged piston, only the ver.7 has them. To the 207 swap, your going to utilize the block if youve got the right heads to rev it out, but if its cheap enough, why not..

You wouldn't be the one trying to sell this block would you?

Plenty of people have revved stock Ej205 and Ej22T rods well up into the 8000rpm range. It's not out of the ordinary. But again, unless he's got headwork and cams that let him go up there, he's not going to be entering that territory. He's sure as hell not going to do it with a vf39...

Nah, im not selling the guy the block, I have a 207, thus giving my input. W/o proper head work anyone reving 8k range is crazy, it doesnt last long, complete 207 w/ heads revs to 8.5 w/o any problems.

Americanyouth,
ALL Ej20's have a forged crank and forged rods. Not ALL Ej207's have forged pistons. Some do, and some have hyperuetic cast pistons. I don't assume it's forged unless they confirm the one they are looking at is in fact forged pistons...

With the GD guys, I assume we are talking about a v7 block, not a GC 207 motor. Although you're right, it could be a v8+ which would not have forged pistons either.

not trying to steal your post, but would a entire Ej207 (full block) bolt into a 02, 03 WRX without wiring?

no..jdm stuff isnt obd-II compatible as far as i know

The EJ207 swap is plug and play in the GDA's. You are correct that they are not OBD II but you can plug in the USDM ECU if you want to trade AVCS for OBD II compliance. You can also get your USDM ecu tuned to run the EJ207. If you use the JDM ecu it can be tuned ( I can't remember if it is Utec or not).

I would not just swap the short blocks or even the long blocks. If you are serious about a stronger block then the crawford, axis, cobb, etc short blocks can be had for a good price. In any case you will need to get head work done and a tune to take advantage of the new parts.

OR as the experts are telling you, Get a good tune on the EJ205. Even though it is not subaru's best block ever, it is still good.

OR as the experts are telling you, Get a good tune on the EJ205. Even though it is not subaru's best block ever, it is still good.

hey thanks, everyone is saying the EJ205 is complete crap and i am about to finish 5 months or hard work to find out the engine i have is complete crap. I know its not the best but i also want to feel i should be able to upgrade it without having to buy a new block.