mx5cartalk.com

Hi all.

I'm new to the forum and new to MX5's.

I haven't been able to find the answer I am looking for relating to the front camber adjustment.
I recently purchased an NB and had a wheel alignment done with 2 degree front and rear neg camber.

I would like up to 5 degrees front camber for Phillip Island. If I buy an offset bush for the lower arm, do I also need a similar upper to get 5 degrees?

Also, can anyone recommend a suspension setup place with race experience near Nunawading or Ringwood.

Thanks in anticipation.

5 degs is a lot of camber on the front! What tyres and suspension are you running?

To get that much from camber bushes you will definitely need them top and bottom. Extended lower ball joints might be a better idea for the lowers as these give you +3 from factory max, whereas bushes are more like +2 at best. (per arm, so +4 for upper&lower together)

fwiw my NB8A orig had only lowers and I could only get just over 2.5deg. I had to do upper as well to get the 3.5 I now run. The fact adjusters are a bit over halfway, so I could probably get 4.5 maxed out, not that I'd want that much camber..

I can get a bit over -4 on the front with eccentric bushes.

rascal wrote:5 degs is a lot of camber on the front! What tyres and suspension are you running?

To get that much from camber bushes you will definitely need them top and bottom. Extended lower ball joints might be a better idea for the lowers as these give you +3 from factory max, whereas bushes are more like +2 at best. (per arm, so +4 for upper&lower together)

fwiw my NB8A orig had only lowers and I could only get just over 2.5deg. I had to do upper as well to get the 3.5 I now run. The fact adjusters are a bit over halfway, so I could probably get 4.5 maxed out, not that I'd want that much camber..

Thanks for your reply. Not knowing the best setup for the car now, I would like to build in plenty of scope for camber adjustment in the beginning. I might end up running much less than 5 degrees. The struts are adjustable Ohlins, wheels are Enkey 15 x 8 with Yokohama AO50 225/50 and front bar is 1mm thicker.

I don't like the prospect of offset bushes as they are likely to alter with use. I like your advice about extended lower ball joints. Where can I get them in Melbourne?

Magpie wrote:I can get a bit over -4 on the front with eccentric bushes.

Thanks Magpie. Do you get any slippage of the bushes or camber changes with hard use? What do you think of extended lower ball joints in comparison to the bushes? Cost wise, the two alternatives apear much of muchness.

No slippage as long as they are torqued up to OEM specs. I have made this mistake before...

The extended ball joint would be the preferable option. Even if you do this putting grease nipples into the control arms will help you keep it nickel greased down there.

Trackphotos has installed them, from memory a write up is in his garage thread.

If you want the rolls Royce solution you could go spherical joints and derlin bushes.

Make sure you keep an eye on your alignment bolts as they as take a hammering in a track car.

Thanks Magpie.
Extended ball joints it is. Spherical joints would be a bit much as I will be driving it to the tracks.

Bauer extended ball joints:

http://949racing.com/SuperMiata-Extended-Lower-Ball-Joint.aspx
https://www.flyinmiata.com/extended-lower-ball-joint.html
http://5xracing.com/b-95910-bauer-limited-production.html
https://www.facebook.com/BauerLTD/

I have the ELBJs fitted to mine and am at -4 degrees with the car sitting at 115m at the pinchwelds.

Why would you want -5 degrees when you plan to drive the car to the track?
I gather this is a road registered car since you mentioned this?
Depending how far you need to travel to the track, you will wear out the inside of your tyres, not to mention your braking will suffer on track as well.

I run -3.25 degrees up front and that is enough for use at SMSP which has long high speed corners. I get pretty even tyre wear. A little more on the outside.
It is also enough negative camber to wear down the insides of tyres driving Sydney to Melbourne and back as I found out from Fanfest. That's with 0 front toe!

I installed ISC Racing Delrin offset bushings in the upper arms to get the camber required.
I can get a bit more negative camber but don't do it as the car also does Motorkhanas and driver training days on Street tyres plus is dríven to all the track events.
The car has Tein Street Flex Coilovers 7kg/6kg/mm F/R running at about 115-120mm to the pinch welds with 225/45/15 tyres. I have the standard front SE 23mm sway bar and no rear.

Link to ISC Delrin bushings
https://iscracing.net/offset-bushing-installation/
The benefit of these over polyurethane is you can lock them in place with a grub screw without them tearing up over time. They are stiffer, but being in the upper arm it's no big deal.
Mine have been in for a while now and have not budged. The only potentially noisy part is the big factory long bolt washers rubbing on the face of the bushings. I have worked out through trial and error that Penrite Moly Grease works well at stopping this and it does not wash away. It has lasted more than a year so far with wet Motorkhanas and track days. No grease is required around the bushing, just the face where it touches the washer.

If were to do the same project again I probably would go with the extended lower ball joints, which I didn't see around when I did my negative camber increase through the bushings.

Thanks a lot guys. All good information. I have ordered a set of offset ball joints which I will instal next week prior to another alignment and corner weighting. The current alignment gives me a little less than two degrees front and two rear to try my first sprint at PI on Saturday.

I'l have some information about the cars performance after Saturday. At the moment it seems to have a front up attitude so I think it needs adjusting ride height lower. Maybe lower all round?

What are the pinch welds and where? What ride height do people find a good compromise?

pinch welds are the long crimped lip of steel aloong thr body under thr doors.

basically the joint where floorpan and uppef body were joined and welded at the factory.

Thanks, makes sense. Now to work out what is the ideal ride height.

Be aware that the lower you go the less camber gain you get.

If you are getting the car corner weighted then you should ask them to check the damper travel/droop and adjust accordingly.