LS swap headers -what did you use?

[sail78385]

Factory LS exhaust manifolds look like the passenger side is going to cause issues, since the passenger side dumps down and back. On the 6.5 Detroit the passenger side goes straight back. Im curious what others have used, seems like the only thing that comes close to mimicking the passenger side is a turbo style header. Has anyone found anything and recycled the Humvee Y pipe?

 

[Swfb]

I have a set of own made headers on my engine. The complete exhaust will be custom fitted to these headers.

 

[sail78385]

I have a set of own made headers on my engine. The complete exhaust will be custom fitted to these headers.

That's awesome! I'm not that talented

 

[Vapor Trail]

I used Speed Engineering LT1 Conversion Swap Headers. They fit pretty good for L86

 

[Anvil Motorworks]

Look into shorty headers. Vaportrail and I have a LT swap using shorty headers as the drop is better. LS headers are different at the flange so make sure you get LS specific shorty headers.

 

[sail78385]

Thanks Anvil… can I just say that I appreciate all your knowledge you pass along. Also, I can’t believe that nobody has made a header specifically for LS in Humvee. Im sure the market is small but to me that along with a set of radiator hoses would really make the whole thing a cake walk. I don’t have a lot of fabrication tools here so it’s advantageous to me to find something that works from the get go. Where I live anything that requires fabrication is incredibly expensive.

 

[Anvil Motorworks]

Universal headers for your LS will work just fine and I would even bet the factory manifolds will work too. It’ll be tight on the passenger side next to the frame rail but it’s doable even with 2.5” exhaust tubing.

As for the coolant hoses I had planned to manufacture hard pipes for the LT swaps but with all the different water pump styles and different inlet/outlet locations, there’s no one size fits all unfortunately. The same is true with the LS. For the lower radiator pipe id recommend using the factory one, then just cutting the end (closest to engine) just after the crossmember. From there you should be able to find a hose to fit. As for the top, I see most people using flex hose. While it’s not my cup of year, it gets the job done.

 

[Vapor Trail]

Every time I see someone doing a swap like this their coolant ports look different then mine so he's giving good advice. I cut my lower ss pipe up and rewelded it in a different configuration and bought several coolant hoses from Summit, Amazon, and local parts store. At the top I though about machining a new housing but finally someone came out with a billet rotating one for the LT so thats done now. They make several of them for the LS. The hose had to be a reducing elbow so that took a while to source.

 

[sail78385]

Every time I see someone doing a swap like this their coolant ports look different then mine so he's giving good advice. I cut my lower ss pipe up and rewelded it in a different configuration and bought several coolant hoses from Summit, Amazon, and local parts store. At the top I though about machining a new housing but finally someone came out with a billet rotating one for the LT so thats done now. They make several of them for the LS. The hose had to be a reducing elbow so that took a while to source.

thanks for the advice! I used the Dayco hose website to dig up some options for hoses and ordered a rotating neck for the lower hose. Hopefully I’ll be able to make something clean and then move on to figuring out the upper. Trying to keep the mechanical fan makes it a little more challenging.

 

[Anvil Motorworks]

If you still need to find hoses like reducers and reducing elbows and such, HPS has a good catalogue of parts to pick from. Below is a pic of the reducing elbow I used to connect my water pump to the custom coolant pipe I made. I’m running an electric fan so I definitely have more clearance but these hoses help a ton without having to fabricate.