Hi,

Building a road race motor and I'm trying to copy what the LS3 does in the TA2 cars. Looking at pictures, I see something weird (or at least weird to me).

The water pump is modified to plug the pressure heater line and they have a fitting on the suction (into the water pump from heater) line. And what they do is route the suction/in heater line to an expansion tank (circled blue). The steam vent ports on the heads are routed to that expansion tank (circled green) and so is the radiator (circled orange).

What I normally see for LS3 steam vent routing is that the steam vent goes to the pressure/hot radiator hose through an adapter fitting. And sometimes I see it going straight into a fitting that's been drilled/tapped into the water pump. And what I've heard is the "best" and "most right" way to do it is to get a bung/fitting on the radiator just below the cap and run the vent line to there.

Any ideas on how/why this works? I'm new to the LS3 steam vent game so I have no idea what they are trying to optimize with the various approaches.