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LTX and LSXPutting LT1s, LS1s, and their variants into Third Gens is becoming more popular. This board is for those who are doing and have done the swaps so they can discuss all of their technical aspects including repairs, swap info, and performance upgrades.
Holy ancient thread batman! So many out there seem to favor the T-fitting into the upper radiator hose or drilling and tapping the water pump itself. I've been emailing back and forth with Kurt Urban who makes a really nice kit for the steam vents and he says that the best place to run the steam vent is to the radiator below the cap area where the radiator fluid is being pulled into the motor to help create a vacuum effect and pull the fluid down. He did say the T-fitting was "ok" and better than not running anything. I've only found one company that makes a radiator that fits a third gen (Supposedly anyway) that offers the steam port, BRP hotrods, but it's $600. C&R and Griffin can both make a custom version but that's going to run near $1000 if not a little more.
I've been emailing back and forth with Kurt Urban who makes a really nice kit for the steam vents and he says that the best place to run the steam vent is to the radiator below the cap area where the radiator fluid is being pulled into the motor to help create a vacuum effect and pull the fluid down.
Post #4. That's where mine is. Stock 3rd gen radiator.
I should have said, "stock replacement 3rd gen radiator". The fitting was used in later years with the heater control valve to shut off flow to the heater core in max AC mode. The aftermarket prefers to stock parts that fit as many applications as possible. So, even though my car didn't have that valve, the aftermarket replacement radiator had the fitting. Much less than $600, cools my LS1 fine. As long as you aren't doing a power adder on the 6.0, it should be fine, too.
I should have said, "stock replacement 3rd gen radiator". The fitting was used in later years with the heater control valve to shut off flow to the heater core in max AC mode. The aftermarket prefers to stock parts that fit as many applications as possible. So, even though my car didn't have that valve, the aftermarket replacement radiator had the fitting. Much less than $600, cools my LS1 fine. As long as you aren't doing a power adder on the 6.0, it should be fine, too.
I should have said, "stock replacement 3rd gen radiator". The fitting was used in later years with the heater control valve to shut off flow to the heater core in max AC mode. The aftermarket prefers to stock parts that fit as many applications as possible. So, even though my car didn't have that valve, the aftermarket replacement radiator had the fitting. Much less than $600, cools my LS1 fine. As long as you aren't doing a power adder on the 6.0, it should be fine, too.
I should have said, "stock replacement 3rd gen radiator". The fitting was used in later years with the heater control valve to shut off flow to the heater core in max AC mode. The aftermarket prefers to stock parts that fit as many applications as possible. So, even though my car didn't have that valve, the aftermarket replacement radiator had the fitting. Much less than $600, cools my LS1 fine. As long as you aren't doing a power adder on the 6.0, it should be fine, too.
That looks just like mine. I believe I got it on-line from radiator.com, or something like that. It cost a bit more than that then, but not much (like $115 or so). I don't remember O'Reilly or Advance Auto carrying them for that little back then.
Ok. So that middle port I'm assuming is where you ran the steam vent to. I'll go with it then. Totally having to buy things for this LS swap that I'd never considered.
I don't have the car to look at right now, tried to find a photo. It's a little grainy (all I had was a cheap digital camera back in 2010), and the fitting is actually closer to the top of the tank as was recommended. It's between the overflow hose and the cooler line.
The steam hose has an adapter in it to go from the small steam line from the engine to the larger fitting on the radiator.
Pressure at the engine will move air & steam to the radiator. Water column in the radiator will reduce pressure differential and slow the air purging process so the higher the hose at the radiator the better. I have no idea if there is a height where the line is crossed between moving air and not moving air. Could be, I just don't know.
I have a manual transmission so I drilled through trans cooler at the upper port of the radiator and used that for the steam line. My own experience is that it works so good that the system will darn near 100% air bleed itself with the car sitting in the garage for a few days. I had to add just a little bit of coolant after running the car the first time. https://www.thirdgen.org/forums/ltx-...ml#post6007530
Regarding radiator, a typical LS engine doesn't need a lot of radiator so a stock 3rd gen radiator is usually more than enough. I have an overside 3-core Modine radiator that I bought when I had the big block and it is way over kill for my LS. My engine exceeded 210F only once during hours of back to back dyno pulls during engine tuning. The shop said it was amazing how my engine never got too hot.
I didn't want to drill into the water pump I bought the upper hose tee. I used the 4th gen fans with the 3rd gen radiator. I cut an upper 3rd gen single fan shroud to fit.
