an American V8 Engine
into a Mercedes 107 Chassis
Most owners find a 450SL's power to be "adequate." It's a heavy car for its size, though, and it's stately rather than aggressive or impressive in its acceleration. In additon, the high cost of an engine rebuild leads many to consider swapping in an American V8 as an alternative to having their 4.5 liter V8 rebuilt when the time comes for a rebuild.
"So why aren't engine swaps more frequently done?"
First of all, there are no "kits" of engine mounts, electricals, and so forth that would make such a swap easier (there are kits for Jaguars, but not for older Mercedes). As a result, every swap is "from scratch" - as a fellow 450SL owner commiserated:
It has been done, though. The Chev V8 in the 1975 450SL to the right was listed on eBay, but the seller wouldn't respond to my request for more info, so I can't tell you any more about it beyond what was in the listing: "This SL mercedes has front tube frame with mustang II rack-pinion steering. The engine is a 1967 396-350 HP. Has been freshen with new rings and bearings. Has eldebrock alum. intake.. New eldebrock carb. Headers and new aluminized exhaust with flowmaster.. 700 R transmission."
How far can you take the concept?
Consider Brad Martin's 1978 450SL Pro Street Hot Rod (below) - the project took a professional shop ten months to complete, working on it 40-50 hours per week. The cost of the conversion was somewhere over $45,000, and the finished car has been appraised at $65,000.
Brad describes it this way: "The car has MB stock suspension with the crossmember modified, new rack, motor mounts, oil pan (double sump) with #10 line to join them together. Custom headers and exhaust. Inner fenders are for looks as is the tin work on the firewall. The motor is a crate ZZ4 Chevy 350 with 355 hp and 406 foot pounds of torque. A 350 trans was used because a 4-speed AT was too big. The rear was tubbed for M/T 29x18.5" tires and a narrowed 9" Ford rear end (4.10:1 gears). An aluminum fuel tank was built to fit between a 2x3" frame from the seats back. Other features include: 1968 Camaro bumpers (rebent and finished without bolts showing), stock MB front brakes, Wilwood Racing brakes in the rear, Boyd wheels (15x7 and 15x14), and stock interior, climate control, and both tops. I'd be willing to sell it for $35,000." If you're interested, email him at email@example.com (Minneapolis, MN)
Not a Chevy fan?
A successful, though very complex, transplantation of a Mustang 5.0 drivetrain into a 1980 450SL is described at http://www.geocities.com/benzswap/. Can you say, "Not for the faint of heart?!"
Nevertheless, the dream persists, and more will be posted here as others share their stories with me. I've decided to go another way - the BIGGER MERCEDES ENGINE swap!
- M D "Doc" Nugent