Two LS1 Heads into a Single Inline-Six Head

1962 Ford Falcon with inline-six motor with head made from two LSx heads

We have seen someone building a V12 out of two inline-six motors and another building a V10 out of two V8 motors. Here is someone making an inline-six head out of two LS1 heads. The builder had reached the limit of the old Ford 300 ci inline-six head after 40 years of racing with it. The motor was built to race in a 1962 Falcon with a Jerico four-speed transmission. Below is the builder’s son explaining the details and process a lot better than I could.

He was looking for an inexpensive cross flow head alternative. He picked up the LS1 heads for $300.00. Its in a 62 Falcon drag car backed by a Jerico 4 speed trans. The epoxy is sealing in the center of the water jackets so it doesn’t see the temperatures you would think. The bore spacing is about .080″ different so two of the cylinders are centered and the rest aren’t. The LS1 head has a small enough chamber that this didn’t cause a huge issue. He uses Comp cams 1.8:1 roller rockers with a solid lifter non-roller cam. Ford 351 Windsor flat top pistons on stock 300 6 rods.

He blocked off both heads with a plate but drilled a hole in the middle to let the water pass through. We considered O-ringing the plates so the heads wouldn’t even need to be attached to each other or like you said running their own water lines. With the 6.0 L heads you may have to make more than one cut in the middle because I think the combustion chambers are larger or a different shape. Dad looked at those too but decided on the 5.3 heads for that reason. When he compared the heads to the 300 head gasket he decided to use the 5.3. There are some other holes in the head on the head gasket surface that have to be blocked. He epoxied in some little plates. They are trapped by the head gasket so they can’t come out.

Also, the block has to be notched to clear the push rods and the push rod/lifter cover plate has to be modified to seal everything up. He started with stock rocker arms with a trunnion kit and adjustable push rods but the push rods would not stay tight at high RPM. Switched to 1 piece push rods and Competition cams adjustable roller rockers with 1.8:1 ratio. The push rod holes in the heads have to be opened up for clearance as well. This is definitely not a “bolt on” project but the only machining he subbed out was the machining of the adjoining head surfaces and then he had the head surfaced after epoxying them together. Everything else was done with a die grinder, a drill press, and his 40 year old hack saw.

The results can be seen in this video.

1962 Ford Falcon with inline-six motor with head made from two LSx heads

1962 Ford Falcon with inline-six motor with head made from two LSx heads

Source: via Bangshift

23 thoughts on “Two LS1 Heads into a Single Inline-Six Head”

  1. Really interested in talking more about this. We are looking to venture down the road of mass building turbo charged straight 6 fords and I want to make an initial build for our prostreet Maverick Chassis. I would LOVE to try this. The Article is a little limited. Thanks

    1. it’s a good looking engine for sure. i’m always interested when ever someone uses an engine that everyone and their brother uses. if it was mine, I would’ve used a “tuned header” meaning all the tubes having the same length. something like a formula 1 header. some ppl call it “spaghetti”

  2. Have you all done anything else with this project? Are there any drawings to help those of us not as good to put the LS heads on our big sixes?

    I will be grateful for any help.

  3. I have a 3 piece welded LS1 head….so that the cyl’s line up perfect….also the water jacket is not the epoxy method. I can send pics

      1. I’m interested in how he did the coolant passages cuz it seems like the exhaust side coolant passage would line up there’s just not as many or bigger holes on the 300 versus the LS but the big problem I see is the coolant passages by the pushrods I definitely like instead of just cutting one cylinder off and doing two pieces doing three pieces so the combustion chambers line up better once I’m out of school I’d love to try and do this kind of a build and put it in an old bronco I’ve also thought about trying to make a roller cam work in a 300 even though pretty much everyone tells me that it wouldn’t work cuz the lifters but I was hoping some way to make the stock 5-0 roller lifters work in there Even if I have to have machine shop somehow bore him out or put in a bushing cuz I think I read that the lifters would be too small in the 300 and oil would leak past but it’s all in my head until I graduate.

    1. Sorry for the extended delay responding to you guys….. life got a bit complicated…. The head is for sale…. I will be driving down to LA from Canada in the next few days and could bring the head with me. open to offers…. cant figure out how to add a picture here…. grrrr heres my email addy…. hit me up ad Ill send pics

  4. Chrysler small blocks and Gen III hemi have 4.46″ bore centers which seem like they would line up better as the difference is .020″ rather than .080″. A hemi head would look better too.

  5. The small block Ford and the 300ci i6 have the same bore spacing, headbolt pattern and water passages. I’ve made a head using two 351c 2v heads. I put the motor in my 66 Econoline van.

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