LS7 coolant expansion tank?

Steven Lobel

GT-R build thread in other forum.
Need an expansion tank and want to fit the needs of the car.

Attached PDF of diagram that I think is correct.

LS7, Superlight radiator, Superlight Vintage Air unit, Heater valve for LS7 ordered from Chevs of the 40s: OAP50-1555.

Factory tank with no overflow attachment, so no good unless I want to risk spilling coolant.

Radium engineering makes a good one but expensive.
Radium Engineering Coolant Expansion Tank | (20-0270-00) – Modern Automotive Performance

How about this? Volvo Coolant Reservoir Expansion Tank - P3 124415 31200320 11853024001

How much overthinking am I doing?
Can I combine inputs/outputs with T-fittings?

Terry Oxandale

Skinny Man
Can't see the attachment. That Radium tank sounds like it could double as a small dry sump tank, and IMHO, extreme overkill on something as simple as this.

This is what I've done, which has been flawless in my expectations. It burps the system with each hot/cold cycle, allows a good vacuum to be used to fill system, and very cheap (which for most of you guys is less of an issue).

Not the exact part I used (cast Moroso remote thermostat tank), but very similar:

Weiand 7134WIN Weiand 6-71/8-71 Supercharger Remote Thermostat Housing


And then send the overflow to larger adjacent tank with a nice billet cap.
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