Radiator Out-let Help for LS1 Plumbing

[badazz81z28]

Gents,



Running my LS1 crossover tube back to the radiator.

My radiator seems to have 2 possible threaded connections built in and both on the same side. Which one should I use? There is one right below the radiator cap, the threads look like 3/8" NPT and there's one about 6" below that which looks like 1/4" NPT....

Does it matter? The top one looks like its meant for a heater hose.

Thanks!

[ccmc]

The top one right at the filler neck should be your overflow.
But the one six inches down sounds like the trans cooler connection. See if there is another one about did inches further down. I'd so the two lower are for an automatic transmission.

Pics?

[badazz81z28]

Yes, directly under the filler neck is the coolant overflow ( I have it hooked up to the overflow bottle). Right under that there is a connection and 6 inches below that is another one. These tap right into the cooling system ( I have pulled them to check).

There is also an additional two for the transmission.

[Northern Goat]

Can't say for sure without a pic, but your rad sounds like my entropy rad, in which case the 1/4 is for the steam line.

[badazz81z28]

Here you go...

[ccmc]

Wow, what a bunch of typos! Damn phone. Anyway, yes next one down just below the overflow is the one your looking for. At least on my ls1 oem radiator that's where the t fitting steam line goes. Don't know what the next one is though. Coolant level sensor maybe?

[badazz81z28]

Do you have a picture of how the stock set-up looks like?

[ccmc]

I'll take a picture when I get home tonight.

[ccmc]

Clear line is overflow
Black line is steam vent
Metal line is transmission
Bottom in pic is capped. Don't know what It's for