Hey all, I have been doing alot of reading & am now more confused than befote I stared. I have a track only WRX with a 2L motor with forged pistons & oil cooler, here in Perth Australia we are now in summer and will see temps around 36 deg C, I have been running ELF 10W50 and would like to change to a Redline 10W40 is there problems with glazing bores with full synthetic oils ? and is this suitable oil ?