I'm looking at upgrading the ej20 in my classic uk impreza soon as I want to take the performance a little further, i'm currently running 330 bhp 300lbft @ 1.35bar, I'd like to achieve between 350-400 bhp/lbft with minimal lag. I am aware i'll need the supporting mods but am not sure weather to use an uprated stronger ej20 0r go for ej25 as the basis of the upgrade? have seen an ej25 advertised and wondered if this would be a good basis and how it was different from the new age ej257? Thanks, Neil.

 

Any thoughts, idea's people? would like to know what would be a good basis for an upgrade? would a strengthened ej20 be suitable? or is the 2.5 route a better bet? thanks in advance for any help /suggestions.

 

Isn't the EJ25 open deck and naturally aspirated? If so then you'll need to change the pistons to lower the compression ratio.

 

would that be the normally aspirated engine from the legacy? I think I'd be better off with the new age ej257 then?

 

Why has my post been deleted?

 

ej257 is good block...I've got one

Gives very nice torque figures with decent turbo

 

Did you change any of the internals mate? i've heard the ej257 pistons aren't very strong and the reliability and strength of the rods and bearings is questionable?

 

OE Sti pistons do have their limits but yes, I did the whole hog and uprated - better safe than sorry.

 

thanks mate for that mate, any chance of a quick run down of what you used? did you build the engine yourself?