Twin vanos cooling system

[jimbo88b]

Hi guys, can anyone out there with a 328/330 twin vanos conversion shed any light on how to set up the cooling/expansion system? I'm not using the original radiator with the expansion tank built in, so i'm looking for a suitable aftermarket header tank. 325 header won't work as there aren't enough inlets. Any ideas much appreciated, thanks, James.

[Motorhole]

One small inlet (from radiator overflow) and one large outlet (to metal pipe that runs alongside engine block) are all you need. The 325i header tank has those plus a 3rd overflow outlet. Lots of people use these, not sure what you mean by not enough inlets/outlets?

[jimbo88b]

I've got two hoses, one is a return from the heater matrix, and the other comes from a union above the n/s engine mount which both go to the built in header tank on the original E46 radiator. The 325i header tank has only one inlet, as you confirmed, from the radiator overflow. So i've got to work out where these two hoses will go, as i assume they need to go to an expansion tank. I've got no metal pipe running along the engine block either, so i've got to work out where the expansion tank will feed back into the cooling system. Donor engine is a 1999 328i twin vanos.

[Motorhole]

Is this what it looked like?



I think the heater matrix return should go to the hose fitting pointing to '11' on the fig; at the back of the engine.

Regarding the hose fitting by the engine mount - I assume you mean the one that connects to the pipe numbered '5'? If so, this is the only pipe from the engine to the header tank.

I don't know whether or not the radiator you're using has an overflow outlet? If so, this would go to the overflow inlet on the E30 325i header tank.

I'm sure somebody else will be able to correct me if I have that wrong