Anyone following the 2019 Barrett-Jackson auction in Scottsdale will quickly realize there is a strong market for well restored G-Wagons. With so much market potential, why not reimagine more G's? The first project for me was turning a G55 into an AMG G55 Squared. I know it was never a production model, but some portal axels, new springs, king shocks, bead lock wheels, and 35" tires... it comes awfully close.
What do to with a sluggish Puch 300GD? Last year I picked up a Getrag 5-Speed from Europe so why not the upgrade the OM617 naturally aspirated 3.0 diesel and 4-speed with an OM617A turbocharged engine with the 5-speed.
I've owned a turbo swapped 300GD before and you can really feel when the turbo kicks in. I'm looking forward to mating it with a 5-speed to increase the top end speed when driving on the highway.
For those not familiar with the OM617 of the '70s and '80s it was one of the most successful and bulletproof engines ever manufactured by Mercedes. Well maintained versions have been known to register over half a million miles without being rebuilt. At only 85 HP, the inline 5 powerplant was not zippy but they did feature good milage and when fitted to cars like the 300D they were well received in Europe and then later in the US. The engine featured a simple mechanical design that, once running, required no electricity.
In 1976 Mercedes started testing a redesigned engine that added turbo. Several records were set and over 200 HP produced was by test models. By 1978 production models existed and in the US it was mated to the W116 that became the first turbocharged diesel sedan. The 300SD became a popular car during the energy crisis ushering in the age of diesel power for passenger cars. As a turbo powerplant, the OM617A produced 121 PS (89 kW; 119 hp) @ 4350 rpm, torque 230 N⋅m (170 lb⋅ft) @ 2400 rpm.
Tuners have been known to squeeze more power from the 3.0 inline 5 OM617A by using high-performance fuel pumps, injectors, and turbochargers featuring intercoolers. Extreme cases have recorded well over 200 HP to the crank although the longevity of the engine will surely take a hit.
I've owned a turbo swapped 300GD before and you can really feel when the turbo kicks in. I'm looking forward to mating it with a 5-speed to increase the top end speed when driving on the highway.
For those not familiar with the OM617 of the '70s and '80s it was one of the most successful and bulletproof engines ever manufactured by Mercedes. Well maintained versions have been known to register over half a million miles without being rebuilt. At only 85 HP, the inline 5 powerplant was not zippy but they did feature good milage and when fitted to cars like the 300D they were well received in Europe and then later in the US. The engine featured a simple mechanical design that, once running, required no electricity.
In 1976 Mercedes started testing a redesigned engine that added turbo. Several records were set and over 200 HP produced was by test models. By 1978 production models existed and in the US it was mated to the W116 that became the first turbocharged diesel sedan. The 300SD became a popular car during the energy crisis ushering in the age of diesel power for passenger cars. As a turbo powerplant, the OM617A produced 121 PS (89 kW; 119 hp) @ 4350 rpm, torque 230 N⋅m (170 lb⋅ft) @ 2400 rpm.
Tuners have been known to squeeze more power from the 3.0 inline 5 OM617A by using high-performance fuel pumps, injectors, and turbochargers featuring intercoolers. Extreme cases have recorded well over 200 HP to the crank although the longevity of the engine will surely take a hit.
I've enlisted the help of the folks at Reinvent the Wheel to design the powerplant for my Puch G. They build a high-performance OM617A with an upgraded camshaft and Bosh M-style fuel injection pump to deliver an additional 40-50 HP over the stock OM617A. The plan is to exceed 150 horsepower when all is said and done.
The upgrade will require the use of some components from the original engine, including the 24V alternator, power steering, glow plugs, flywheel and vacuum pump. I'll need a new clutch, for the 5-speed and a new shorter driveshaft. Once complete the truck should have better performance at altitude (I live at 7000' elevation) and at highway speeds.
Look for a full review when the truck is finished in a couple of months.
Once complete, the "turtle" will be going to the body shop for some touchup bodywork and I'll get started on bringing the interior back to its original spartan military specifications.
