Garage Star Delrin Door Bushings

[★ revlimiter ★]

I've driven around 75 miles with these door blocks over a lot of different surfaces. I have some feedback.

Car: base 2001 NB with a rollbar. There's like no bracing on Bucky at all. No diagonals on the rollbar either. The windshield shakes CONSTANTLY. Or at least it did.

I installed the blocks with one of my beloved JIS screwdrivers (shameless advertising) and went for a drive. The whole car felt immediately transformed. The windshield hardly shook and I could actually feel the front and rear suspensions being independent of each other. I only got cowl shake on one bump on this test drive. I was hugely impressed.

I then drove around 50 miles the next day. The car started out nice and firm, but by the end of the day, I was seeing some windshield shake and the car was feeling more like a normal Miata. I was a bit disappointed. I figured that the first day was just new-part-excitement and maybe things weren't as magical as I was imagining. I don't have any NVH meters after all. It's all subjective. But it definitely felt shakey.

When I got home, I installed Sharka's door blocks. I did this with a ratchet since no JIS screwdrivers were handy at the time. I was amazed at how much the bolts kept tightening down after I felt like I'd gotten them tight. The delrin smooshes down a pretty good amount. On a whim, I opened up Bucky's driver door and tightened down the door blocks there. The driver door? TOTALLY LOOSE. The screws had worked their way loose and were barely finger tight. I zipped all 4 down with the ratchet (passenger side was decently tight still).

On the next Bucky drive (today), the feeling of strength and rigidity returned. Bucky felt like a real car again, and that feeling lasted all day. I covered about 35 miles today over a bunch of surfaces. The "Miata feel" of a wet noodle with a shaky windshield never came back.

I effectively gave myself a blind test. I had no idea that the door blocks had loosened and I could definitely feel something had changed when driving around with them loose. I'm rather amazed this happened. It was an awesome blind test to take.

So. These things WORK. I imagine Ken will be extremely busy making these since 100% of all Miatas on the planet require them. It needs to be one of the early mods every novice Miata driver does: rollbar, shift knob, vent rings, door blocks. Not necessarily in that order.

I'll have a ton of photos posted as soon as I get some driving impressions with Sharka. That car has a ton of bracing and doesn't shake much at all. I'm guessing the blocks won't be as noticeable, but we'll see.