NA Camber adjustment (> 1deg)

[takai]

Just bought an NA, but gave it a bit of a push on the way home. Feels squirmy in the front end, like it is rolling over on the tyre when cornering. Normally i would run about -1.5 - -2 deg on this style of double A-arm setup, but it looks like the eccentric bolts max out at about 1 degree.

On the US forums i read that their primary solution is extended lower ball joints, but that could be because SuperMiata are massive over there.

What other options are there for greater than 1 degree negative camber? Car is primarily for track days and occasional street driving.

[Magpie]

Has it been and had an alignment yet?

Yes extended lower ball joints and or eccentric bushes, however only -1 degree suggests other things may not be right down there...

[greenMachine]

Isn't the NA front subframe (K-mount) camber-limited, compared to the NB subframe?

Even so, that seems low. Same both sides? What pinch weld height?

[takai]

Haven't had a chance to test it out for certain, but from the geometry and adjustment it looks like it maxes out at -1.1 or so. But if in reality it cambers in more, then ill go with that.

I have to replace a ball joint anyway, as its knocking a bit, and thinking i may as well pop extended ones in rather than standards if that is the normal way to go.

[Dean.H]

My NB could get a bit less than 1 deg on one side, a bit over 1 deg on the other side. Nothing was easily visibly bent.

I installed extended ball joints however they developed play after about 3 track days. They sent me some free replacements which I wasn't going to put in, but my car chewed out the offset poly bushes I put in as replacement, so I've gone back to the extended ball joint and non offset bushes. Seems to be holding up ok now, but I haven't been driving the car much either. Bauer were developing some improved design extended ball joints when I had the issue, which might be in production by now (?)

By the way, I think offset poly bushes can work, you just need to pin them carefully in place, or get lucky!

You may wish to also consider an offset Delrin bush in the upper arm only. This works but reduces clearances to the inner guard. Only an issue with lots of camber and big tyres.

[takai]

My NB could get a bit less than 1 deg on one side, a bit over 1 deg on the other side. Nothing was easily visibly bent.

I installed extended ball joints however they developed play after about 3 track days. They sent me some free replacements which I wasn't going to put in, but my car chewed out the offset poly bushes I put in as replacement, so I've gone back to the extended ball joint and non offset bushes. Seems to be holding up ok now, but I haven't been driving the car much either. Bauer were developing some improved design extended ball joints when I had the issue, which might be in production by now (?)

By the way, I think offset poly bushes can work, you just need to pin them carefully in place, or get lucky!

You may wish to also consider an offset Delrin bush in the upper arm only. This works but reduces clearances to the inner guard. Only an issue with lots of camber and big tyres.

Hm, so it almost sounds like a complete adjustable control arm might be a better option, with standard bushes and ball joint?

[ManiacLachy]

No, just get the extended lower ball joints from Bauer. It'll be a minimum of fuss and cost, instantly increase your max negative camber by 2 degrees. Easily replaceable and reversible in minutes. Doing adjustable control arms is a big job.

The new production versions have just been released. I think the change is just a reinforced body, I don't think it's anything to do with the actual ball joint.

[Dean.H]

Hm, so it almost sounds like a complete adjustable control arm might be a better option, with standard bushes and ball joint?

only if you have the time, skills, and really want to do it. Even though I did have issues with the initial extended ball joints, above advice is right that extended ball joins is probably the easiest way to do. Keep a close eye on them before/after track day. Your call though of course.

I happen to have some new extended ball joints here that I'd sell you for less that what you could get them for if any interest.

I'd suggest turning up at your local state mx5 club track day and talking to people with similar cars, or with mods you'd like to do. Bring your car and have a drive at the same time!

[takai]

Hm, so it almost sounds like a complete adjustable control arm might be a better option, with standard bushes and ball joint?

only if you have the time, skills, and really want to do it. Even though I did have issues with the initial extended ball joints, above advice is right that extended ball joins is probably the easiest way to do. Keep a close eye on them before/after track day. Your call though of course.

I happen to have some new extended ball joints here that I'd sell you for less that what you could get them for if any interest.

I'd suggest turning up at your local state mx5 club track day and talking to people with similar cars, or with mods you'd like to do. Bring your car and have a drive at the same time!

Ill flick you a PM. Im already talking with a bunch of 2B guys and others down here in Vic.

I have made the move into the MX5 from an IPRA AE86, so I am no stranger to car setup etc. It is mainly the little nuances between cars that im wondering about. Normally on a dual wishbone setup I would just set it up with a pair of heim jointed ends. But given that this is a cheap weekend racer, having the option of using a proper ball joint is attractive.

[Magpie]

Hm, so it almost sounds like a complete adjustable control arm might be a better option, with standard bushes and ball joint?

NO, these are not available for good reasons! Even if you find them for sale on Ebay check to see if they have any supply. There are rear adjustable arms available and these do not have any major issues. I have them on mine (track car) and one of the lock nuts gets loose every now and then. Since I put a drop of loctite on it 6 months ago it has not moved.

These may be what you need http://sadfab.com/bushingpackages.html

[Luke]

-1 degree on a NA up front is pretty much the maximum you will get.
On my NB SE I could get -1.5, but that is because they were lower and have the updated NB8B geometry in the frame.

Now I was really unlucky, I did my front negative camber increase before extended front lower ball joints were a thing or at least I dod not know about them many years ago.
I went with offset bushing in the upper A arms.
I did a fair bit of research before doing it and stayed well clear of all the Poly ones as they apparently rotate under load, more so in the lower arms then upper.
I went with ISC Racing Delrin offset bushings for the upper arms. You lock them into position with a grub screw so its set and forget, or at least thats what they say. As I found after about 1 month they were squeaking way worse than any poly bush would. I men like a kid jumping on a old metal sprung bed base. They do need grease to stop this unlike ISC say. Delrin is not as sell lubricating as advertised.
With my coilovers I can get as much as -3.5 degrees camber up front.

However if I were to do it again I would be doing the extended lower ball joints. That is what everyone I talk to at track seems to use now.

Saying all this there is a advantage or disadvantage for both methods as well dependent on your wheel and tyre choice. With the bushings in the top arm you will gain more clearance on the outside of the front guards, but less to the spring. I found that the front guards are more limited for space on the outside than the rears and rears can gain a lot more with rolling, at least on a NB. So for me with 15x8's with a +32 offset fitted with Yokohama 215/50/15 A050's fit in very nice with the offsets. I think my tyres could possibly just rub on the outside front guards if I had the extended lower ball joints with this wheel tyre combo.
When I had 225/45/16 on 16x7 +40 rims the inside of the tyres was just touching the metal body work next to the top of the spring. This is sort of relevant as 225/50/15 is the same rolling diameter.

[Junkwhale]

What's your ride height? The static camber is related to where you are in the camber curve based on ride height. The lower you are the more negative camber will be possible. At really high (anything over OEM) you'll struggle to get into the negative at all.

[CrazyRacer]

NO, these are not available for good reasons!

I have seen plenty of adjustable front upper arms advertised, both with rubber bushes and spherical bearings and was wondering why you say not to use them???

[Magpie]

I have seen plenty of adjustable front upper arms advertised, both with rubber bushes and spherical bearings and was wondering why you say not to use them???

Safety issues, they break. I will try and find an email from one of the previous makers of them which gives reasons why they do not sell them. The rear adjustable are fine, front I personally would never use.

[takai]

I have seen plenty of adjustable front upper arms advertised, both with rubber bushes and spherical bearings and was wondering why you say not to use them???

Safety issues, they break. I will try and find an email from one of the previous makers of them which gives reasons why they do not sell them. The rear adjustable are fine, front I personally would never use.

If they break then they were not built properly. Plenty of cars built and even sold brand new with adjustable tubular A-arms.

Factory 116 arms, the 211 ones came with threaded sections for adjusting camber and caster.

There is nothing inherently dangerous with adjustable A-arms, and heck with the MX5 upper arms being essentially symmetrical it spreads the load even better than asymmetrical arms.