Hey all,

Getting ready for next weekend track event. Just finishing the gutting on the M3, and I've removed the heater core. What do I do with the 3 coolant lines that are now open? Do I plug them, or loop them? Since there are 3, which are needed? I assume I can also remove the heater control valve.

All you mod guys speak up with your setups!

Well, on my p-car there are only two and they are being plugged. No sense circulating hot water.

Ok ... removed the heater control valve, so now I have the 2 hoses (makes sense). Do I plug them, or loop them? :help

I plugged them. I had James at RRT make up some delrin plugs which fit in there and are held in place w/ hose clamps.

Hmmm ... talked to a few local guys here, and they looped them. So is this like a personal perference thing, or is there a "right" way? What would be the reasoning behind doing one or the other?

Thanks!

Hmmm ... talked to a few local guys here, and they looped them. So is this like a personal perference thing, or is there a "right" way? What would be the reasoning behind doing one or the other?

Thanks!

With any car, you'll want to loop them I'm thinking the M3 is the same. Circulating water is not a waste; it will play a part in cooling the engine. The heater core also helps cool the engine when water is flowing through it. Not sure I would get rid of it unless you are terribly concerned about its weight.

Nik

The heater core also helps cool the engine when water is flowing through it.

Very minimally compared to having a proper cooling system. Keeping the heater core for "cooling" is a very bandaid approach to simply making sure your radiator is up to task. The weight savings and the lack of scalding water entering the passenger compartment of a race car are two very good reasons to ditch it if rules allow.

You need to loop them

The hoses to the heater core are in the circuit of the thermostat bypass.

The BMW cannot use a restrictor or just remove the thermostat like other cars, it is a system that opens one route while it closes another. By just putting plugs in the bypass circiut for the thermostat, you will be preventing the thermostat from working consistently.

Excellent! Thanks for the responses, and the good background info. :redspot