One Hundred More Horses Set Free
The newest dish on our menu of conversions is the BMW M5 – which our team has taken from 441kW to 515kW – a gain of 74kW, or a solid 100 horsepower!
Torque, meanwhile, surges to 907 Nm from 750 in showroom form and there’s no compromise on the delivery either: at just 1 500 rpm it has already climbed from 355 to 420Nm. At 6 000 rpm, there’s still 735 on tap, almost as much as the standard engine’s maximum twist, which is achieved at 4 000 rpm.
We’d like to think we’ve taken Beemer’s performance sedan to the next level with this Stage Two conversion for the M5.
The first thing we changed was the exhaust: out went the standard outlets to be replaced by an RGM-Techniflow system painstakingly built by our welding gurus. The downpipes from the V8’s turbochargers are also new and the quartet of catalytic converters has been dispensed with. It measures 76mm in diameter and is fabricated from 304-grade stainless steel, using a combination of mandrel bending (which leave interior diameter unchanged) and pre-formed sections. As the pictures show, dozens of pieces go into the construction.
The individual behind the mask plays a huge role in the outcome and it is skill- and labour-intensive work to achieve this level of quality.
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The tail end, installed pre-assembled, is a maze of intricate piping with a transverse silencer per bank of cylinders. It continues to utilise the original dual-tone exhaust volume control (or M Sound Control in BMW-speak) flap system which is integrated into the Techniflow exhaust. Owners who find the M5 a little too subdued appreciate the deep and rich exhaust tone this bypass function creates, which leaves no doubt as to the car’s performance credentials. There’s also more ‘crackle’ on the overrun…
To maximise the benefits of the exhaust RGMotorsport turned to software experts, JB4. Their M5-specific solution integrates seamlessly with the car’s CANbus wiring, maintaining all the original drive-mode functionality including the exhaust volume control. It also allows for electronic wastegate control for superior boost targeting, allowing maximum output to be safely achieved.
Cost of the conversion is R110 000 including VAT. Talk to our sales team about the options on the M5, including a further upgrade which unleashes even more grunt and is designed for use with our own RGM Torque race fuel!