KA overheating

[240sxfamily]

Okay, we picked up that s14 on here for 650, Did 5 lug swap, well still in process, 300zx brakes, put carpet and headliner in it, and the leather seats and a wheel. Now, for the engine, before it was leaking coolant real bad, tightend all the rad hoses and it stopped..has a ebay radiator(from PO), new tstat, and new waterpump(us). I believe its a head gasket or the temp sending unit. cause heres an exp.

We pull out of walmart, the guage is below c, 1 mile down the road its above H...is that really possible for it to heat up that fast? the motor runs like a charm.

Its got 110k on it if that helps, i mean if its a blown HG no problem we got them stocked so we might do that either way, but its just time we dont have right now, he bought this as a daily, so we can work on the other s13s and the track s14.