Why Do LS Engines Have Steam Tubes?

What are these crazy looking tubes on my LS and why do I need them anyway?

In an LS engine, the thermostat is in the water pump housing, which is locating much lower on the engine when compared to the old SBC set-up. With the LS design, the temperature and flow of the coolant are regulated before the coolant ever enters your engine.

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HOLLEY ON SOCIAL:

[mikeypooh]

I’ve seen many videos addressing this issue, but this one provided an exceptional explanation without fill-in material trying to push their products.

[TheReinoPaasonen]

These holley efi and LS videos are best in the industry. Thank you Holley!

[stoneyswolf]

The SBC 400 has steam holes in the cylinder head. If you install aftermarket cylinder heads and don't drill them you can have overheating problems.

[TheBarnCarsandBicycles]

pretty sure the big kit with the merge block won't fit under a stock LS1 or LS6 intake. Does Holley have a solution?

[moreclips]

Ive got a really interesting question. Can i use a steam port connection as a temp fix for a blown head gasket? Exhaust is getting into my cooling system and it displaces the coolant into the overflow tank. Wondering if i can vent those fumes with a simple t connection on upper radiator hose. Extra line leading to the drain of my overflow tank 😂 so janky, but in theory do you think it would work?

[TexasNova]

They do not recommend routing it to the Water Pump 2:19. Needs to be routed just under the Radiator Cap

[darryloflife]

Good point now concentrate on the water pump and see if it performs according to the required flow rate and head pressure for the heat output of the engine. You will find as we have that the water pump is the most important component on an engine, in order to bring about a proper tune spec. Both Ford and chevy woke up to this a few years ago which is why they placed the thermostat on the inlet. There is still alot of work to be done.

[bryancingel]

So if mine are having problems. Would this cause over heating while driving? It stays normal at idle but when I drive it over heats

[knucklestheechidna]

Could you not put a t fitting on the hose going from the reservoir to the radiator and hook steam vents up to that?

[icebergnews]

Can you please tell me if coolant is supposed to be a steady flow back into the radiator on a Chevrolet LS6.0
Thanks

[liveandletlive]

So coolant is flowing in it out of those 2/4 holes on top of the engine?

[RideUnited]

I have 5.3 240sx turbo, u think with blocked rear steam ports and just the front steam line will be ok? 2003 5.3 stock 706 heads

[Pittaz]

What do you recommended for a throttle body bypass setup on an ls1

[nyplantingsgardendesigners]

Do the later model LS7 have a different setup? I tried swapping my 2006 LS7 kit onto a new GMPP LS7 crate engine and the adapter that bolts over the steam hole dowel is too long.

[monkeymph]

If you vacuum fill the cooling system you shouldn't have a problem

[cristianh]

So I can just refill my engine coolant by just putting coolant into the radiator? I’m on a ls swap and I have my fitting on a water pump spacer

[CVPI]

where can i get the AN fitting that goes on radiator?

[jamesdriscoll]

the cold water come in though the thermostat ? thats what the vid shows at :45

[waynenz]

why would you want to tap into water pump to circulate steam back through engine

[jeffbowman]

This is total crap... just another way to make a buck.