LS Swap Radiator Hose Adapter w/ Steam Port, 1.5 Inch - 1.25 Inch

• Provides standard LS steam port connection without modifying existing radiator
• Adapts LS 1.25-inch water pump hose to standard GM 1.50-inch radiator hose
• 1/4-inch hose barb fitting connects to LS steam line fitting on engine block
• Black powder coat finish blends in black rubber hoses for a discreet look under hood
• No custom LS swap radiator purchase required, saving you money on your project

Reuse Your Existing Radiator for Your LS Swap with Our LS Hose Adapter

There’s no doubt that one of the reasons the LS swap is so popular in GM muscle cars is that the overall cost to do the swap is relatively low. We didn’t say cheap, but it is certainly a cost conscious way to go when you need to repower your classic GM muscle car or truck. Though grabbing a salvage yard Vortec 4.8 or 5.3, cleaning it up, and adding a few necessary items like swap headers and engine mounts will get your new to you LS under the hood, there are several other aspects of the swap to consider, such as the cooling system.

Unlike the older SBC or BBC, the LS engine family features a thermostat that is in the water pump housing. While this design allows for temperature and flow to be regulated before the coolant enters your engine, having the thermostat at a low point means that any air in the cooling system can easily get trapped in your engine. Air bubbles in cooling passages disrupt coolant flow, create hot-spots, and can cause overheating issues, pre-ignition, and detonation. Fortunately, there are steam ports in the heads that allow this trapped air to flow away from critical cooling locations to a high point outside of the cylinder heads. Since these engines utilize a closed pressurized cooling system, the steam tubes must be connected back into it at some point. 

A swap specific aluminum LS radiator is generally considered a must have item for the LS swap to be successful. The LS radiator is designed to mount like the stock radiator but features the proper steam port connection and a smaller upper radiator hose bung to function properly with the LS engine. This is great if you have no radiator to put back in the car, or perhaps your radiator is junk, and you need to buy a new one anyway. However, there are plenty of LS swappers that have a perfectly functioning radiator in their GM muscle car and would rather spend their LS swap dollars elsewhere than an expensive LS radiator swap. Enter the Speedway Motors LS Steam Port Radiator Hose Adapter, a runner-up for the 2020 SEMA Best New Street Rod/Custom Car Product Award!

Solves All of Your LS Swap Radiator Hose Issues with A Quick and Easy Install

Our LS swap radiator hose adapter solves several issues related to the LS swap cooling system hose routing configuration without looking like you spent a weekend in the plumbing section of your local hardware store. No one wants to see brass NPT fittings cobbled together to make the LS water pump outlet hose connect to your original radiator. Not to mention the more fittings you use the greater chance of leaks or parts failure due to vibration.

Our budget-minded hose adapter provides a clean and simple solution. It features one 1.25-inch end to match the LS engine’s water pump outlet, along with a 1.5-inch end to match the upper radiator inlet on standard GM-spec radiators. This solves the two different hose ID issue, but we went a step further and added an integrated streamlined 1/4-inch 90-degree hose barb fitting for the LS engine’s factory steam line port on the block. This provides an LS steam vent radiator hose solution that simply attaches inline in the upper radiator hose.

No longer do you have to consider having your radiator modified for a steam line port or use some clunky fittings to create a LS steam vent radiator hose setup in your upper radiator hose. To top it off we use a black powder coat finish to blend the LS swap radiator hose adapter in with your rubber radiator hoses for an OE look that just fades away under hood. Pick from our dozens of cooling hose and tubing options to finish your LS swap cooling system hose routing and you’ll be that much closer to twisting the key on your fresh LS swapped ride.