If you’ve been following our work here at Partee Racing, you already know how passionate we are about the BMW S62. It’s a phenomenal engine—powering cars to Rolex 24 victories and giving enthusiasts something special under the hood. And while many folks often bring up rod bearings or vanos as its trouble spots, let me say it again for the people in the back: neither of those typically cause catastrophic engine failure. But one part does—and that’s the dreaded U-shaped chain guide.
Over the last 10 years, we’ve probably disassembled more S62s than any shop in the U.S. and in that time I can’t recall a single one that didn’t show some form of U-shaped guide degradation. The culprit is well-known by now: six tiny clips that secure the brown plastic guide to its cast aluminum backing. Over time, they go brittle, break off, clog oil pumps, and in some cases, interfere with timing chains and flat-out stop the engine.
So we said enough is enough. We didn’t just tweak the old design—we scrapped it and started fresh.
After months of design iterations and obsessive prototyping, we’ve landed on what we believe is the final form of this part. It’s not just an upgrade; it’s a complete reinvention. First up, the material. We went with Stanyl 46 TW341, a top-tier, high-heat polyamide. If you’re into materials science, you know what that means: high wear resistance, high strength under stress, self-lubricating, and excellent thermal performance. It’s what the OEMs are using in their highest performance chain guides today and a significant step up from the cheaper PA 66 polymer that the OEMs use in many guides.
Our U-shape guide is then bonded to a billet aluminum backing—CNC machined from 6061 aluminum. This isn’t the cast aluminum junk that BMW included in their original design. It’s precision-cut strength.
We ditched the fragile clips and replaced them with three interlocking lugs and a self-tensioned fit that literally becomes its own clip. You don’t simply pull this guide off the backing. You wrestle it off.
And because overkill is underrated, we added three staking pins, inserted into the Stanyl 46 from the back of the billet aluminum backing and locked in place with green Loctite and chamfered stakes. Those pins aren’t going anywhere—and even if they wanted to, the engine block is in their way.
Triple redundancy. Zero excuses.
We didn’t stop at structure. We addressed flow and fitment too:
This guide is plug-and-play—if your idea of play is obsessive engineering.
We’ve already started installing these in real builds, including one of our tech’s own engines. It’ll see 2,000 to 3,000 miles, then be torn down and inspected for wear before we commence pre-sales of the guide. Our confidence in the fit, performance and durability of this part, however, is total. That’s why it comes with a lifetime warranty. If it fails? We replace it. Period. (You wouldn’t get a new engine in any circumstance, but you would get a new guide.)
We’re targeting a regular retail price just under $900. Yes, it’s significantly more than the stock $395 piece—but it’s also the last U-shaped guide you’ll ever buy. If you’re already investing $8,000–$10,000 into chains, tensioners, and vanos, skimping here makes no sense.
As I’ve said before: if you’re going to invest that much into your S62, don’t cheap out on the piece that’s most likely to kill it.
We’re not stopping at the U-guide. Next up: the bank 1 tensioner guide. We’ve already started prototyping it with Stanyl 46, proper oiling holes, and a better fit than anything stock. And yes, we’ll probably tackle the final fixed bank 2 guide just for good measure. Our current vision is a full chain guide kit—all redesigned, all lifetime-rated. One kit. One install. Zero worries ever again.
If you’ve made it this far, thank you. This guide has been a labor of love, frustration, and more than a few shop debates (all of which I won). But we’re proud of what we’ve built, and we’re excited to get it into your engines.
Be well, and go fast.
—Peter Partee
