Hi can anyone tell me the differences between 2.0 ej cylinder blocks for normally aspirated and turbo, wrx and Sti ? Is it possible to build a forged turbo motor starting with any block as long as the crank rods and pistons and the rest of the engine are for a turbo motor ? The reason I ask this is because I have a very good condition 2.0 N/a block which I was thinking of using to build a forged turbo motor therefore saving me the aggro of having my car off the road for longer than needed. It would be great if I could build up the bottom end before I take my engine out. Any info would be great thanks
Pete.

 

you will need a turbo block too start with the cylinder liners are alot thicker than the n/a blocks.

 

Oh ok thanks for that Pete, didn't think about cylinder wall thickness, the bore and stroke are the same so I just thought there was a chance the blocks were all the same.

 

Are you sure about this? Please share your source of information. Did you tear down and compare the two engines or do you have some documentation from Subaru showing this difference?

I have always known that the turbo and N/A blocks are exactly the same (except for the N/A blocks possibly being open deck even if the corresponding turbo block was closed deck).

 

I too am interested in the facts behind this. I made an SR20 det once from a std primera gti block, it held up very well, with no reportable failure.

 

i thought that the blocks were the same only the internals on WRX/STI were stronger then N/A but the blocks it self were the same.

 

crank and rods are the same on 2.0 NA and 2.0 wrx turbo i belive also

 

I have fitted turbos to Vw golf 1.8 normally aspirated gti engines with no failure, I've also fitted 16valve cylinder heads to 8v engine blocks with no problems that's why I was hoping I could use the na block I have now for a turbo build I always thought that all the blocks came off the same production line. I think I'll have to try and compare this block I have here with a turbo one, Unless someone can give me more info on this thanks for the input fellas

 

Hi all never stripped a n/a block so only going of what ive read.
just looking for the book now pretty sure its got pics to show the different cylinder wall thickness s

 

might of got this slightly wrong on the 2litre block 2.5 n/a block deffinately different to the turbo block cylinder liners alot thinner
pic 1 ej20 turbo block
pic 2 ej25 n/a block

 

Thanks for taking the time for posting the pics, the only problem being that they are ej20 and ej25 comparisons and prehaps not the best to compare? Still be really interested to find out if there is any differences between ej20 na and turbo casings

 

No difference....

The 2.0L N/A & the 2.0L Turbo Wrx engines both share the same block casings.

Just to be certain of this (as it's been a few years since I was building these engines) I have checked the official Subaru parts program & it lists the same part number for both.

 

Thanks a lot pee vee that's just what I wanted to hear
And thank you everyone else for your input on this thread.