Thanks ph1. The car is a 1995 model and it definately is a crack. The car has plenty of big$ bolt ons but the rb26 is internally stock. I have access to a mates standard RB26 that I want to build with forged pistons, balanced crank etc but this would be done over trhe next 12 months. If I buy the car now I am hoping the slight loss of water will not create other problems until I perform the transplant. What do you think may have caused the crack? I have heard only impact to the motors ancillaries such as power sterring pump bracket can cause the block to crack but after several investigations I can confirm this car has not been hit in the front. It is running a modest 1.2bar.