I have a 280zx turbo that is burning a huge amount of coolant. After letting the car idle for about 20mins it burns through the reservoir tank. White smoke is coming out of the tail pipe. I am not sure if the engine over heats because after 20mins my whole garage is full of smoke and its hard to breath. I pressurized the radiator and it held pressure for about 10 mins, so there are no leaks in the cooling system. I also did a compression test on the engine and the numbers where 145, 141, 148, 147, 147, 148. I did the test again but adding oil this time and the numbers where 162, 160, 161, 162, 160, 162. I ruled out a head gasket problem since all the numbers are the same. I checked my oil and there is no coolant mixing with it either. The car has been sitting for about two years. I have replaced just recently replaced the turbo and starter. Thanks for your help

 

Still sounds like a head leak....

 

Head gasket, or cracked head. Do a leak down test with the motor warm.

 

and don't breath that stuff in man, it's dangerous, probably even more so because of the burning anti freeze

 

Thanks for the help guys. I just finished doing the leak down test and it points to a cracked head. I have been looking around for a head and found a N42 in my area, Do you think that putting a N42 head on a F42 block would better then replacing it will a P90 head? I know the N42 head will create a higher compression ration then the P90 head. I also know that the P90 has bigger combustion chambers and slightly raised valves. If I where to put the N42 in I would have to make sure there was enough clearance between valve and piston. Is there anything else that needs to be check or modified for this set up to work? any input would be greatly appreciated.

 

I doubt it's "cracked". It's probably warped / blown head gasket.

Pull the head and have a machine shop check it for you (usually free).

 

P90's warp all the time. Pull it and put a straight edge on it. You want a P90 - it's the best stock flowing head you can get.

 

Thanks for the help guys I will try to take off the head sometime next week and I will let you guys know what is wrong with it.