The Kneeslider

Doers Builders and Positive People

DIY Quarter Scale Fuel Injected DOHC V8 Engine

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Quarter scale DOHC fuel injected V8 engine built from scratch
Quarter scale DOHC fuel injected V8 engine built from scratch

There is a subculture of incredibly skilled hobby machinists turning out work that is awe inspiring for anyone who has ever stood before a milling machine or to those who simply appreciate great work. This V8 engine, built entirely from scratch, is one of those “best of breed” examples; fuel injected, double overhead cams, serpentine belt drive for the accessories and a smooth running sound that just amazes.

Double overhead cams, all from scratch
Double overhead cams, all from scratch

The project has a very detailed, two year long thread over at Home Model Engine Machinist, where builder keith5700 details everything he did, the troubles he ran into while learning his way through the tough spots and photos galore. You need to go through the pages to appreciate what he’s done.

Machining the water pump impeller
Machining the water pump impeller

This isn’t some CNC masterpiece, this is a manually machined and sometimes even hand machined project that looks like the full size prototypes it emulates. Those intake pipes on the manifold were roughed in on the mill then hand finished with a grinder.

Combining the skill in design, machining and finishing with the technical knowledge and skill of incorporating the fuel injection makes this a real masterpiece.

This isn't his first machining project, this is a 1/8 scale helicopter rotor assembly for a model
This isn’t his first machining project, this is a 1/8 scale helicopter rotor assembly for a model

He’s done some beautiful non-engine work before, too, the 1/8 scale helicopter rotor assembly is pretty spectacular in its own right. This is what a lifetime of learning, working and practice leads to, stunning work that can be appreciated by a wide range of hands on builders as work of the highest caliber. Very, very well done!

Thanks for the tip, William!

Link: Home Model Engine Machinist

Comments

      • I am wondering if he had to make it all? What about the cog belts for the cams? Or those little sparkplug wires.

        • The belts were made, but he made the cogs.
          The sparkplug wires, are just wires.
          The fuel injector started as an automotive one, he took the coil/pindle etc out and drilled the smallest hole he could for a spray plate. That one single injector is under the plenum, spraying upward, fogging the intake. Its triggered by a Megasquirt.

          He made the tiny spark plugs, machining an outer sleeve, and pressing a electrode through a hollow core and then pressing that into the sleeve.

          all this is in the build thread.

    • Thanks for the link!!!

      This V8 and the many beautiful projects displayed in the museum are inspirational. I have a desk drawer full of pretty parts that should assemble to be a running 43cc v twin. It had a serious design issue, though. I’m going to give it another crack soon. This time it will be 33cc of unrestrained thunder (I hope).

  4. amazing job, whish I had the man’s skills.

    stil found one small imperfection : there is a bolt missing on the the intake calshaft sprocket on the right cylinder bank 😉

  5. People who can do fine machining work like this are true legends in my book. They create works of art.
    I worked for an R&D company for a while and they had many a machinist with similar skills but I suspect they didn’t have the LOVE for doing it like this guy. Amazing!

  6. Wow, This thing is amazing. I’m really digging that rotor assemble, too. I’ll have to check out this guy’s build thread.

  7. Hey GM! TAKE NOTICE! DOHC V8 based on an older 350 TPI setup. Seriously?! This is more than cool!

  8. Some of the questions you guys have about spark plugs and fuel injection are covered in his build thread. It’s DIY, all the way. He’s good.

    I’ve been seeing more of this happening in some other projects where the builder has to figure it out as he goes and ends up succeeding doing what he didn’t know how to do beforehand. The technical complexity of the projects is rising, too.

    This is what it takes to succeed in anything and these days, with almost any knowledge you need available for the asking, it’s how much ambition and determination you have that sorts out those who do and those who don’t. I like it.

  9. As a machinist I see a beautiful finished product but I also know the amount of time that has been invested is monumental. Who covers his ‘honey do list’? Who’s mowing his lawn and who is riding his motorcycle?

  10. Hrrm, a quarter scale v-8 DOHC…. assuming its true to scale, that puts it at roughly 87.5 cu in, and given that many chevys put out 300 hp… that means a theoretical 75 hp. lets detune it to 60 hp, just for sake of argument, however the LT1 had a 360hp option…

    ok so, 88 cuin,60hp beautiful sounding little motor… could be right at home in a motorcycle… afterall the TC88 in a softail ran 67hp. But the COOLNESS factor is multiplied by 100, and its actually ridable unlike the boss hoss.

    PLEASE tell me that the guy that built it is watching this thread…. lol