Top-Gun

I'm installing upgraded ARBs on my car, the ROW M030 22mm front and ROW turbo 21mm rear. I bought the correct bushings as per the PET.

The rear calls for bushings with part #477 411 313 D. These bushings are quite a bit smaller in I.D. than 21mm. I was able to get them installed with the clamshell brackets tightened up against the subframe, but the split in the bushings is splayed open and the bar doesn't rotate freely.

I'd suspect these were the wrong size, but a quick google search uncovered pictures of 911s with ARB bushings that look similar when installed. Does anyone with a 21mm rear ARB recall their bushings being like this?

If this is how they fit I think I'll opt for aftermarket polyurethane replacements and live with having to lubricate them periodically.

Thanks.

Top-Gun

Picture of a 911 with a similar condition to what mine look like installed.

k722070

try using a washer as a spacer between the subframe and mounting bracket.

JasonAndreas

The last letter in the part number is supposed to correspond to dimensions but according to PET, somewhere in the mid-90s that part number may have become a 19.5mm bushing.

nine9six

When I installed my M030 ARB and bushings, it look nothing like your photo and I strongly suspect those are the wrong bushings. Why not order your bushings from Sunset Imports, since they aren't at all expensive. I ordered both rear bar and bush from Sunset, years ago.

This doesnt make sense, based upon what we see in the photo. If smaller, I would not expect to see the gap between the bar and bushing.

Top-Gun

That would make sense that it changed to a smaller ID bushing, as these definatley don't look right.

I ordered these from Porsche so my concern was that ordering another set with the same number will yield the same result. Maybe these were old stock or something.

samurai_k

Assuming you ordered the right parts, then when I have experienced with new bushings they were hard to install brand new. What I found is get some longer bolts or a c-clamp and use them the seat the bushing with the clamp. Then replace the longer bolt with the right hardware once set. Also spraying the bushing with some spray silicone helped with the install. In my build blog below I talk about it when I installed my front ARB last fall.

IainM

Top-Gun

Just a follow up in case anyone comes across this thread in the future. I went back to my local dealer and had them check the descriptions on the part numbers, both correctly stated for 22mm and 21mm sway bars. Reordered and they came in exactly the same.

The issue is not just isolated to the rear bushings, the fronts also appear too small when installed. I measured the bushing IDs of both the fronts and the rears and they measure 20mm front and 19mm rear. I'm confident the fronts are correct as the part number ends in "22" and there are two beige dots on the side of them, matching what I've seen others have.

It appears to me that Porsche intentionally runs these with a 2mm interference fit. Perhaps the gap in the bushing appears to close with use as the bushings find their happy place in the clamshells. I was able to make the rears look better by coaxing the bushing closed with a large flat screwdriver while tightening the clamps, but theres still a gap. The fronts are too tough to access while dealing with the PITA clam shells so they have an even bigger gap.

In summary, if you install these and think you got the wrong bushings as they look too small, they're supposed to be that way from what I can tell.