After removing the original rubber door bushings, fit the replacement delrin units and thread the bolts in by hand and close the door. Open the door note the position of the door bushing before torquing the bolts down.
If the door has difficulty closing or you prefer to alter the fit you may sand some material off the bushing.
Good-Win Racing Staff Notes:
Sean @ GWR: Without a doubt this is one of the quickest modifications I have ever performed and also one of the best. Go over some train tracks or joints on the freeway and you'll immediately feel the chassis absorb the imperfections with reduced noise, vibration and harshness.
Had another brands door bushing on my 95 NA and honestly didn't feel a difference. Maybe because i had more done to that car.
So I was a bit skeptical on the ones for my NC. I must say, i 100% truly felt a difference. Im actually kinda shocked as I already had the notion in my mind that these weren't going to do anything and I wasted $70... But boy was I wrong.
What definitely sealed the deal for me was, I have a noise in the front of the car, most likely bad control arm bushings as the car has 170k on the chassis. This noise/rough feeling was felt inside the cab when hitting speedbumps, divots in the road etc. Would feel it literally every time I drove the car. Didn't bother me much as i somewhat knew the issue.
Now with the door bushings...that noise/thunk will not go pass the firewall. It is nowhere felt in the cab. Completely isolated to the engine bay/front suspension. That really made me go WOW.
Anyways, thanks for reading. If you dont have them yet i would highly recommend them.
Honestly one of the most cost effective and easy mods I've ever employed. My car feels a lot better on the track and on the streets. The doors close with a satisfying thud and I could tell immediately that the overall chassis stiffness was substantially improved. If you have sways, shocks, tower braces or anything like that but haven't done this, you're not getting the most out of your other improvements. Buy these now.
My Miata was flaccid in the door section. After installing these Delrin Door Bushings (installation was super simple) the car had never been more stiff. WOW I noticed a difference immediately! Even my girlfriend, who rarely goes for a ride, noticed the additional stiffness. Better handling and I could feel the curves better, too!
everything you have heard is true. should be standard equipment for every na or nb miata. previously had to creep over cattle guards. now I can go over them at 15 to 20 mph and it feels just like a little unevenness in the road.
These flat out work in tightening up the cockpit over expansion and sharp, abrupt bumps. I had to shave some material off though to help with opening my door as the fit was super tight. Overall, very worth the $60. GR