Calling all gear-heads; Custom Motor Build


I speak fluent Vise-Grip
One of the guys that works for me is a serious gear-head. He lives and breathes octane. He's very well known in the local racing circuit as the guru of HP. He can build an engine like nobody's business. And like most of us, he's usually willing to spend more on his hobby than some folks think is reasonable. He's not one to take extended vacations; he'd rather spend his money on pistons, intakes and carburetors.

Anyhow..... He just finished a custom V-12. Yep; that's 12 cylinders, folks. He took two 302 blocks and cut the front two cylinders off one and the back two off the other. He welded the blocks together (and the total runout of the main bearing bore was 0.002 before he line bored it!). For the heads, he cut one in half and welded it to the front of one head and the back of another. When he put it all together the block and head welds were staggered.

Of course, he had to build a custom intake and exhaust. The first intake was fairly complex because he built a cross-over setup with plenum boxes on each side and six outboard carbs, but it proved to be way too much flow for the motor. He ended up doing another welded build with two standard intakes and mounted two 700 CFM Holleys. The exhaust was easy; he bought a couple of header kits and routed it all together.

The guy he sent it to for boring fouled up and bored it 0.040 over, so his first pistons were useless and the guy had to buy him a new set of pistons ($700 for the set -- ouch). He had a custom crank machined; I think he said it was a little less than $4K, but I could be mistaken. OF course there's a custom cam too. He built a planetary gearbox to run two 6 cylinder distributors and feeds one bank off of each. At any rate, it's a beautiful machine now that it's complete.

Now for the money. 552 CID, 385 ft-lb @ 2600 rpm, 584 ft-lbs @ 6400 rpm and 697 HP @ 6900 rpm on pump gas (93 octane). It's as smooth as a buttered jet engine (and probably uses a similar amount of fuel). He hasn't decided what to do with it yet but was considering building a GT40, Mark IV around it.

Feast your eyes.....

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You can see the original cross-over intake in the bed of the truck in this image.
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This is the planetary box driving the two distributors.
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Well-known member
Interesting build. Pretty smart guy and great builder, but those HP numbers seem low for that many cylinders


I'd build a bike around it. This would be badazz. But the most amazing is this guy. Being a mechanical engineer myself i can appreciate it. I wander why no major car builder did not buy him as a major player for some serious development.
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