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"SL from Hell": The Monsterous 2005 RENNtech Stage 3 SL65 AMG

This 2005 Mercedes-Benz SL65 was modified by RENNtech at a cost of $22,000 when still new, and as a result, is now producing a mind-bending 700bhp and 900 ft-lbs of torque. Its no secret that AMG-tuned R230 cars – especially the top-of-the-line, twin-turbo, V12 SL65 - have substantially more power right out of the box than their stock counterparts. This particular example, however, adds a fist-pounding 96 bhp and 162 ft-lbs over the “stock” AMG monster. Find it here on Ebay out of Lyndhurst, New Jersey. With over 5 days to go, this RENNtech/AMG tire-slayer is already at over $37,000 with reserve not met, but we’d venture to guess there’s plenty more bids to come on this one.

The Cubanite Silver Metallic (aka Pewter) paint seems to shine well despite undetailed reports of a non-airbag accident in 2008. The original 2-piece AMG wheels claim to have been recently powder coated (in the correct finish) and are a rare and expensive set on their own.

Regarding this car’s extensive performance modifications, the RENNtech Stage 3 package goes beyond the typical “tune and badge” treatment with a full RENNtech ECU upgrade; 3pc Full Carbon Fiber Airbox; RENNtech High Flow Intercooler Pump Kit; Stainless Steel Performance Mufflers; 100% Locking Differential; and a RENNtech Transmission Performance Upgrade. Without the transmission upgrades provided in this “stage 3” package there is little doubt that the stock Mercedes 5-spd transmission offered in 2005 would last barely beyond the quarter-mile with this much hp & torque.

RENNtech badges are present on the front fenders but AMG badging is retained in the rear (below the questionably-styled rear lip spoiler) and on the badly cracked and sun-faded AMG cluster. Cosmetics seem to otherwise be in line with what would be expected on a well-cared for 2005 vehicle with under 38,000 miles.

These R230 SL65s have retained their value better than their W220/221 counterparts with nice, lower-mile examples regularly selling in the range of $35,000+. It stands to reason, therefore, that this RENNTech-tuned example should be no exception; assuming there are buyers that actually want MORE power than the factory-offered AMG SL65 beast. The seller states that “all receipts and service orders are in hand…by certified Mercedes-Benz dealerships” but makes no mention of the original RENNtech paperwork provided with the upgrade work. Its likely included with the aforementioned paperwork but serious buyers should consider confirming as such.

Despite the seller’s New Jersey location, the “autocheck” report substantiates seller’s claim that this is a “Florida car” and thus, rust-free. The previous four owners (not including the seller) appear to have all been in the Naples, Florida area.

Even without the RENNtech upgrades the R230 SL65 is a very special hardtop convertible roadster that should garner the interest of any modern Mercedes enthusiast. Thus, with the addition of the stage-3 RENNtech goodies, this car should now command their attention.


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