UK and Jap engine differences
 

does anyone know the physical difference between the classic WRX Jap and UK engines. i would have thought the piston design may be slighty different on th jap to the uk due to the jap engine running a more aggressive ignition map and more ignition advance due to the 101-103 ROn fuel. therefore the pistons take a bit more of a battering, so are they any different to the UK ones? also what is the difference between a WRX engine and a Wagon engine.
i believe that the wagon has a slighty smaller turbo? is this true?

cheers

chris

The wagons do have the smaller turbo,but i dont think there is any difference in the engine.

AFAIK,the uk and jap engines are the same,its only the sti engines that are different.

Cam differences between UK and Jap, Pistons are the same.

Rob

so based on the cams being the only difference, will a wagon engine with my old turbo from my WRX go into my WRX and run ok? or will the cams cause me grief with the original subaru engine map?

yes

Rob

as long as you are talking about using your saloon ecu and not the wagon ecu

yes i will be putting the engine from the wagon into the WRX and putting my old turbo from WRX onto the wagon engine. i will continue to use the jap ecu that is in my WRX.so just to clarify this will work ok?
i bought the car with a dash 22 actuator and chipped ecu. when i bought it, it was running 1.25bar (i had it turned down to 0.9 but still often peaked at 1.05-1.1bar). boost was raised via a bleed valve which is what think did the damage to the jap engine. i will keep the actuator but ditch the bleed valve and replace it with an electronic boost controller. i wish to raise the standard boost level but what level is safe? im running the standard IC with a ARC induction box and a full BPM exhaust.
thanks for your help
chris

1 bar is about max if it is the old slanty type intercooler , also are you running standard injectors 380 cc with standard fuel pressure if so you will be almost maxing these out . personally i would not turn the boost up at all until you have a knocklink for detecting detonation and a AFR to indicate fuel mixture , as the import ecu is set for 100 ron fuel not british 98 ron optimax and the ecu is all ready running advanced timing for its set up of 100 ron so if you then put low ron fuel in and up the boost you may well be getting detonation and that is what damaged your engine , you say it has a chipped ecu , which one if it is a scooby ecu this converts it to run on english fuel and retards the ignition , other chips just fool the ecu by altering signals and don't adjust for british fuel, just my advice i also have a 93 wrx and have purchased all the above as well as a later model intercooler and can say that the car runs great with no signs of det .

good luck


Mark