Expansion tank plumbing with no heater

[txbuilder]

I am doing a non-GTM build with the LS engine and I am wondering if anyone has any information about plumbing the rear expansion tank using the heater input and output run through the expansion tank without a heater core in the system. Can this create any sort of problems? I just wondered if maybe the volume of flow might be more than necessary and if that might create any problems.

[crash]

Nope. You should be fine. I would make sure to run the steam vent line to the tank, but other than that, you should be able to just mount the header tank high and have full flow through it and all will be good. This higher flow will also ensure that the thermostat works properly. Yes it takes a little bit of flow out of the cooling system that goes to the radiator, but not a significant amount. Remember that the flow through the main lines is darn near equivalent to the flow through a fire hose!

This is exactly how the header tank on the GTM-R will be plumbed.

[txbuilder]

Thanks, I will get it all installed and post the results.

[VD2021]

I am doing a non-GTM build with the LS engine and I am wondering if anyone has any information about plumbing the rear expansion tank using the heater input and output run through the expansion tank without a heater core in the system. Can this create any sort of problems? I just wondered if maybe the volume of flow might be more than necessary and if that might create any problems.

If I'm not mistaken Kemp plumbed his rear tank bypassing the heater core. He's in PR.

[Kempo]

As Vidal said that is the way I did it. I also ran the steam vent line to the fitting on the side of the tank as Crash recommended. No ill effects so far at least with car standing still since I still can't go kart it. The temperature goes up and as soon as the fans turn on the temp goes down.