Seeking comment, guidance, etc. on the following proposed setup that I am building for my '07:

Suspension: KW Clubsport 11K springs all around with Hardrace front camber thing-a-bobs
Sway Bars: Front Eibach, Rear Miata NC FSB (I think I am getting the softtop version, have to check)
Wheels: 17X9 +60something all around (probably just get the Tire Rack brand STR class wheels)on RS3's (doubt I will go R compound yet, but might)
Ride Height: ???? suggestions welcomed before I search more on this topic
Alignment: ???? suggestions welcomed before I search more on this topic

 

Is this your daily driver? Do you care about tire wear?

It seems to me that 11K springs all around will cause a lot of oversteer, especially if you don't have a very stiff front sway bar or ultra soft rear sway bar. I just now got my car to be more neutral (after battling oversteer for years), but I have 10K front springs and 8K rear springs with a Saner front sway bar set to medium.

 

Gernby,

Not my daily, drive the car mostly to track events and maybe once a week or so.

Thanks for your comments... and I agree with you:
I am somewhat concerned with the full square (spring rates and wheels) set up. It seems most STR setups are softer in the rear. I was hoping the bigger than OEM Eibach front bar (I was going to get a new/used SANER bar from that group buy, but decided not to) and softer than OEM Miata FSB on my rear will kill some of the oversteer.

At worst, I may just have to pick up some stiffer front springs or softer rear springs.

 

There's a set of CR struts with Swift Spec R springs for sale in the classifieds.


CR Spring rates

Front: 7.0kg/mm=392ft/lbs

Rear: 6.2kg/mm=348ft/lbs


Spec R Spring rates

Front: 7.5kg/mm=420ft/lbs

Rear: 7.0kg/mm=392ft/lbs


For a track based car your definitely going to need those camber joints in order to get the right alignment/neg camber especially with a square set uo. As for ride height, stay away from excessive lowering, the swift Spec R's I believe lower the front/rear 1.25 inches.

 

Steve,

Thanks for the spring info, but I will be running full coilovers (KW Clubsports). Bought them from a group buy on S2K.

 

David, you had a chance to ride in mine with the OEM suspension, Euro alignment and a Saner FSB on med.
I got a bit of understeer, but it did feel a lot more planted than your current set up.

I hope the KWs and sways help you get your loose back end under more control.

 

Thanks Pete.

Part of the plan was to get 17X9 wheels all around. The wheel purchase is going to be delayed for awhile. So, I may just install everything that I have and try to adjust the car for staggered setup... we'll see.

 

I would definitely suggest a softer rear spring with a "square" tire setup.

Currently I'm running AST 5100s with 600F/500R spring rates, a Whiteline front bar, an NC MX-5 softop front bar in the rear, and "square" 17x9s with 255 RS-3s. Before the MX-5 bar in the rear, my car was still quite loose on corner exit, even with the staggered spring rates.

This fall work should finally slow down enough to let me back out to the track, and then perhaps I can finally run the new setup at MSR.

 

I would say that setup would be a good start, but with the Eibach front bar you might need to run no rear bar. How stiff is the Maita bar compared to the OEM AP2 rear bar? Sounds like it is a little softer than the OEM bar


And I dont think you will need the camber adjusters. How much camber are you wanting to run in the front??

 

Thanks for the input!

Since 11K is about 616 my spring rate is similar to Alitain's. Maybe with the staggered tire and bars it could be neutral on even springs? Someone within the racing forum did a comparison on the Miata bar to OEM and it is definitely less "springy/stiff" than the rear OEM bar.

Also, I haven't decided on amount of front camber. 2.5? 3? not sure how much would be necessary on the street tires (probably not as high as 3). I'll just keep reviewing the STR thread in the racing section.