F430/360 Challenge bushings maintenance ??

I'm using the F430 Challenge bushings in my Scuderia, as the stock bushings have too much flex for high grip tires (Hoosier A6).

The white plastic (delrin I think) presses in the control arm. I use Castrol bushing grease before pressing them in the control arm. I use more grease in the inner of the bushing, so the pass-through part of the flanbloc slides properly. These pass-through pieces are supposed to be tight to the bushings with no play at all.

My problem is that they start making annoying noises after a little while. They tend to get some play with the pass-through piece, at this point they become noisy. Some brand new bushings already come with play, whether I get them from the Ferrari parts counter, or manufactured by a machine shop.

It is an annoying task to remove the 8 control arms and press-out and press-in new bushings. I have done it 3 times already, and have yet to do it again. I get worn out bushings in as early as 500 miles.

So, is there a way to get stronger delrin bushing, use a special grease that prevents wear, or a different design (not a monoball, cannot use) that lasts longer?

I don't want to go back to the rubber stock bushings. The stock bushings did not produce any noise, despite of the inner bushing being a metal to metal contact against the pass-through part from the flanbloc.

Once they get play, the dynamic toe and camber has play as well, and the car develops a vibration at very high speeds (harmonic vibration from the geometry play).

Any help is deeply appreciated.

 

It helps a lot. I didn't know that there could be such a massive tolerance for a piece that is supposed to have a snug fit.

The factory bushings have play, most of them. I bought 24 of them on the first batch and only 3 came snug. Later on I bought 20 bushings from a machine shop in Texas, and 12 came tight.

I started keeping a spreadsheet rating how tight was every bushing for every control arm on the car, since the 2nd change. I noticed that the ones that were tight at the install time stay good a lot longer, I have 2 bushings in the rear that still have the original Ferrari Challenge bushings and they are fine.

I think the ones I got from the Texas machine shop are Delrin, not sure. They are not as white as the stock Challenge ones, but they still look and feel soft compared to the Delrin bushings that I have seen for Hondas and Corvette, and they wear out rather quickly as well.

I'm going to try using zero lubrication on the bushings (first need to find a local machine shop in Los Angeles with the strongest delrin raw material available).

Thanks a lot.

 

The ones I'm getting custom made on the last batch were good on the outer edge, all of them have a snug fit, but the inside is a problem.

I just inspected mine, and definitely they are getting sand trapped because of the grease (accelerating wear), and I agree that once they have play they accelerate the wear.

The downside on these bushings is that once they wear out, the dynamic camber/toe gets variations, and there is a vibration at high speed (harmonic vibration) coming from the wheels.

I'm going to keep tracking on the longevity of the 4th set, if they last one year I'm happy camper with that, but it is annoying to change them every 2-3 months.