RMM...old COBB vs Powerflex

kaminari · 2026-05-21T07:48:52-0500

Hello everyone, many years ago on my ST Mk7 I installed the Cobb RMM, the old version with the holes. It got damaged and I need to replace it, but I’ve seen that it was updated with the new version without holes due to “resonance issues.”

How does the yellow+purple Powerflex RMM compare to the old COBB one I currently have and to the new version? No track days, just spirited street driving.

Thanks!

Switchback · 2026-05-21T12:17:43-0500

Honestly the Rear Motor mounts have come a long way since the first few options (Boomba, OG Cobb, etc). I probably wouldn't spend the money on the Powerflex mount, you can get similar from Whoosh or even ebay specials (Which Ron gets his mounts from China anyway).

The Bushings will fail over time unless you splurge for the rubber ones, but given the cost difference I'd just go with the cheap one and budget for a replacement in a few years when the bushings wear out.

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RMM...old COBB vs Powerflex

kaminari

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