Hi Everyone !

i have a 2003 WRX ,and need to replace my shortblock because of a broken piston ring, and 150.000km on the clock ( sorry i'm from italy) . So now i'm gooing to replace the entire shortblock with a OEM one from subaru and was considering to put a spec C EJ207 on it beacuse it costs the same as a EJ205 shortblock , so in case in the future i want to build up the motor i already have a good block , but for the moment i'm ok with 300HP .

My question ist about the compression rate, if i'm not wrong by putting an ej207 shortblock i will reduce de compression right ? .... how can i keep the same compression like the stock wrx ?? I'dont want (if thats possible) to have tha car tuned again because it was done new 3 weeks ago....


What is the compression on a stock ej205 and ej 207 ?

Thanks

Oliver

 

The same - 8.0:1

 

so why does the compression sink with the ej207 block ? Is the difference in the STi head gasket ?

 

depends on the age of the EJ207 but the later style pistons (after MY03) are hyperpeutic and not particularly strong...........

 

it will be a 2011/14 JDM spec C EJ207

 

you mean the 'thick walled' very weak one??
very poor choice IMO for higher power due to a machining relief / flaw in the cylinder walls meaning they have a tendency to split liners under aggressive use