Yes, You Can Put LS Heads On A Ford 300 Inline-6, But It's Not Gonna Be Easy

Having gotten to examine Allen Millyard's welded-together Kawasaki V8 up close at the Barber Vintage Motorsports Museum, a bucket-list item for sure (sadly, his Kawasaki V12 was in storage at the time), it seems that if a genius builder is sufficiently motivated, no engine project is impossible. Weld together motorcycle engines to make a V8 that not only works, but works like it came from the factory that way? Just give him time. 

Having also explored the stupendous similarities between Ford's Windsor and GM's LS V8s, and finding that there are people actively working to make LS heads on Windsor V8 blocks into viable engines, it's time for an LS-headed Ford project that's not only been done to completion with real running results, but has been done multiple times: GM LS heads welded together and bolted to Ford 300 inline-sixes. It's actually been done so much that a forum user called InlineDave87 over at FordSix.com says he grabbed some no-name aluminum small block Chevy heads to graft together because "I was just wanting to go outside the norm of everyone piecing together LS heads."

Now, don't go thinking that because this swap is relatively common it's also easy. The only reason it works at all is because the Chevrolet LS's 4.4-inch bore center spacing and the Ford 300's 4.48-inch spacing are close enough, though only two cylinders will end up perfectly centered. The head and block bolt holes also line up almost exactly, with the largest difference being 0.05-inches.

Pushrods come darn near fitting, though the block does need notching so they'll mate up with the lifters and not scrape. Everything else? Get ready for serious fabrication, from custom-length pushrods to a bespoke pushrod side-cover.

One of the more prominent LS-300 projects belongs to Ken Hutchison, who runs the Tall Garage YouTube channel. His engine is in the "running" list, with the first startup happening in September. Hot Rod, which had been following the build, connected Hutchison with Holley Performance Brands, which gave him a set of Hooker exhaust manifolds. Hutchison promptly sliced them up and welded on a T4 flange for a turbocharger. The engine sounds like an angry bear being woken from hibernation:

This is the culmination of over three years of work. Hutchison's inspiration came from Ken Ellison of Ellison's Machine Shop, who built a Ford 300 featuring a head made from three Boss 302 heads that were cut into six segments and welded back together. Since Boss 302 heads are expensive and rare, and LS heads are decidedly not, Hutchison went with the LS heads. 

The flow rates aren't super far off, either: Boss 302 heads, which are dang close to Ford's 351 Cleveland heads in design, flow 279.5 cubic feet per minute (cfm) on the intake side and 186.5 cfm on the exhuast side with 0.6-inches of lift, while the 317 6.0-liter LS heads Hutchison used flow 243.3 cfm intake and 193.7 exhaust with the same lift. Granted, the Boss head's intake flow is superior by over 30 cfm, but that's nothing a good porting wouldn't take care of. 

Plus, Hutchison didn't have to segment the heads like he was cutting up carrots for a stew. He simply sliced off one chamber each, making two three-combustion-chambered sections to weld together. Well, "simply" isn't fair. Hutchison ended up with a boomerang-shaped head he had to machine flat.

Then there's Jaron Nelson's LS-head-shod Ford 300. It's also turbocharged, and he's shooting for 500 hp at the wheels, but there hasn't been a dyno run yet. Recently, Nelson posted a video of the engine running in his '35 Chevy rat rod on his YouTube channel, Piston Ranch:

Nelson went with a four-two approach, basically grafting an extra pair of chambers onto a complete head. His big-brained approach includes a coil-on-plug ignition like a Ford Taurus SHO V8 and a custom harness he made out of scavenged bits from a bunch of Chevy Suburbans.

Back in 2014, user 512Fairlane on the 429-460.com forums shared photos of his dad's finished LS-six in the engine bay of a 1962 Ford Falcon, which was done with epoxy holding the head pieces together. It looks gorgeously gnarly with triple Holley two-barrels, and this build would make Allen Millyard proud. As 512Fairlane explained regarding his father's process in a comment on BangShift, "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."

Finally, perhaps the most extreme build yet is this "Crown Hick," or an old Ford F-100 body plopped on a Panther Platform Crown Victoria:

Yes, that's an LS-headed Ford 300 with an 8-71 blower! Unfortunately the owner wasn't around to start it up for the guy filming. Even more unfortunately, there's a dearth of info about the build online. If you built this or know more about it, please spill the beans.