how many holes to drill in thermostat to increase cooling efficiency?

[CrUZida]

I haven't read anywhere Brett stating that he's had the stock radiator professionally cleaned?

["Z" UTE]

Similar situation at the workshop last week. the guys chased all over the place to try and fix an overheating problem.

Customer advises that there is a reco radiator fitted.
The lads changed thermostat, radiator cap, and water pump. The bloody thing was still overheating. Gave the engine a complete tune with a sniffer up the tail pipe to check lean running.

The boss called the customer, and asked where the radiator was reconditioned. "That one came from a wrecker". Sure it looked good, with a nice shiny coat of black paint. but the flamin thing was partially blocked. A proper "reconditioned" radiator was fitted. No overheating problems now.

cheers Chuck