I have an 85 w150 with a 318. The guy I bought it from said the engine was rebuilt recently, but every time I tried to fix the timing, the vacume advance hit the firewall (no more room). I found the issue was with the distributor drive gear being off 4 teeth. I fixed that and re-installed the stock intake with new correct gaskets. Ran like a top, untill it overheated in 3 minutes time. With it running, the top radiator hose was cold, had no pressure. I took off the radiator cap and it was flowing, but was clearly a mix of oil and water. Droplets fo water on the dipstick too. This was never an issue before I fixed the timing issue. I got new intake gaskets and put them in. It had a new thermostat too. The old gaskets were in place perfectly too. I am going to finish it up tomorrow and flush it & start it. Any ideas on what would have caused the oil & water to mix? Also, can heads and intake from a 360 fit on with no mods and would I buy 360 head gaskets or 318 head gaskets? Please help this newbie out.

 

iirc the 360 heads have larger port volumes and you may lose power by switching to them, unless you've got high rpm goals to take advantage of the extra flow capacity.

but I've read about so many different head combos that they're all muddled in my mind now.

 

How is the coolant level? Overheating and water in the oil might be the result of a blown head gasket (or worse).
Regards,
Greg