KanseiKat

Where are you guys finding OEM bushing kits? Yes, I searched, sorry if it's been beat to death. The closest to OEM (and cheapest) I can find is the $400 FM high performance rubber set.

aidandj

iTrader: (5)

Yep, thats the cheapest ive seen.

Arca_ex

iTrader: (2)

Can't wait to get this **** on the car. Most pumped about the offset bushings, I'm 9000% sick of outside edge wear.

KanseiKat

Well damn. For a little bit more than FM rubber how could I not get a delrin kit. I'll have an order in soon as I figure out exactly what I need.

Are the four bushings that aren't delrin included in the kit? I'm guessing they're rubber if they are, and the higher price up is for poly/bronze.

aidandj

iTrader: (5)

They can be included. They are poly. See here.

hi_im_sean

iTrader: (3)

Ive got 2 or 3 more kits to do, and then ill make you next. Did you want to just bring the car over and we can do them as we go? or?

Any races in the next 3 to 4 weeks? We can get just the offsets in there sooner, like this weekend, if needed.

Leafy

iTrader: (1)

Yeah thats about what I can buy OEM ones for.

Arca_ex

iTrader: (2)

Nah, not going to bother changing the car for the next event, already working on other changes. Just going to do bushings/coilovers/corner balance/alignment all in one go.

I'm doing the Pro East event on Feb. 20/21, then on the 22nd I'll check on the status of the coilovers and if they are on schedule I will just take all the control arms off the car and bring them over. The next "deadline" would be the NASA east event on March 5/6. Probably want to be ready to corner balance and align by Thursday March 3rd, so three weeks from now.

hi_im_sean

iTrader: (3)

That'll be close, but we'll play it by ear.

Oscar

iTrader: (2)

So after reading all of this I'm better off selling my fresh set of powerflex bushings and making my own from steel and acetal at uni for just material cost?

hi_im_sean

iTrader: (3)

That, or bronze your poly kit.

Yes, "bronze" is now a verb.

Oscar

iTrader: (2)

Bronzing sounds good. Easier to sell off complete PF set and machine my own sleeves

Alternative

Would it be easier to increase the sleeve size to 20mm and use 40 or 50mm OD Delrin tube? Could cut down a bit on machining, prices I've been seeing is ~$12/ft

hi_im_sean

iTrader: (3)

No. I use 7/8" sleeves which is 22.22mm. 20mm is a decrease and would be to small for the camber locations. Also the OD should ideally be a bit bigger than 40mm to aid in the interference fit, and you would still need to drill out the bushings after pressing them in still anyway. Never mind the fact that they all have shoulders. I also doubt the ID of plastic tubing is held to any of sort decent tolerance.

mx592

iTrader: (2)

Maybe this was mentioned in another thread, but why 863 bronze over 841? I realize 863 is stronger and has a higher load capacity, but doesn't the iron content make it prone to rusting? Is the extra bearing capacity necessary? I can't imagine any single bearing seeing even close to 1500 lbs. of load under hard cornering...a 1G (~2500lb) cornering load, even if all of it was directed through just the lower arm of one wheel would still be divided among roughly 4 bearings so the per-bearing load would be only 625 lb.

Leafy

iTrader: (1)

Factor of safety, bigger that is the longer the bearing is going to last in an application like this.

hi_im_sean

iTrader: (3)

It wont rust seeing how its oil impregnated and alloyed with copper. Periodic greasing with the zerks will also mitigate or eliminate any rusting that would occur.

Although static loads in cornering may not exceed bearing load, shock loads will. Rumble strips, pot holes, etc. Although im sure 841 would work without cracking in two, as leafy said, 863 will wear longer. Its only about $35 for the entire car to use 863 over 841.

thumpetto007

iTrader: (15)

So did I **** up by getting these?

Energy Suspension Bushings Miata

aidandj

iTrader: (5)

Not at all, especially if you have a street car. I would say poly is by far the best budget option (if you don't have access to a lathe).

Delrin is very stiff, and also requires a lot of labor to machine (instead of just being cast like poly)

See the details about the bronze bushing conversion kit if you want to get rid of some of the binding issues with poly.

That being said 90% of track miatas run poly, and it performs perfectly fine, it just isn't the best solution

mx592

iTrader: (2)

So what about delrin bushings inside of the poly? If solid delrin bushings work with the bearing loads that these part see, then why wouldn't a delrin sleeve inside a poly bushing? You can buy tight tolerance 3/4" ID x 7/8" OD tubing (+/-.010") for $5 per foot, which is CHEAP!!:

McMaster-Carr

Or you could go with oversize tube and finish it to the necessary size if the above tubing proves to be too sloppy:

McMaster-Carr

Or you could go with igus bearings for $2.74 each in quantities of 50:

igusĀ® Plastic Plain Bearings: iglideĀ® J

I am considering these options along with stainless sleeves - possibly precision ground 440C or even 17-4 PH if I can successfully drill it.