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Needing a pretty tidy Suspension Upgrade for the NB Build.

Looking to dial in a progressive predictable tarmac rally setup for road use and track work,
focus will be on high speed stability and braking an area where the NB suffers compared
with the NC platform.

I have decided to go for a Custom SPAX Build as specified by Greg Nolan from SPAX Australia,
it works out at a mid priced $3,800 and includes custom pillowball mounts choice of springs etc ...


Another option I had was to get bespoke Active Suspension made this would been $4,400
in parts and a bit of R and D to and from to Melbourne but still has promise.


MCA GOLD Series is a bit on the high side at $6280 but might have been worth it once fully dialled in.


Next question is what complementary upgrades were helpful eg.

- Nolathane Bushes
- Strut Braces
- Chassis Bracing
- Aero


Thoughts from any tarmac rally types or racers.

As per the strut brace thread, get the base right so the suspension will work.

How far are you willing to go? As you can see from my S14 build I started from a bare shell so have built a cage and seam welded the shell for maximum chassis stiffness.

If not looking at pulling the car down to nothing, look at seam welding the engine bay and some bracing for the chassis and suspension sub frames to body connections so movement is kept to a minimum. The stiffer you can get the chassis the better the suspension will work and the more you can fine tune to your requirements and driving style.

I'd class this as over the top.

https://www.facebook.com/media/set/?set ... 569&type=1

Inboard rear suspension.

Why don't you ask the experts. MCA weren't keen on urethane bushes in general and recommended changing back to stock sway bars for my application.

Given the money you've spent else where... Buy the golds, the wtac results speak for them selves.


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Just going to throw my two cents in here as I have been talking to a heap of the national Tarmac guys myself.
Basically they all run standard rubber bushes in their cars as most aftermarket ones have no room to give and end up making the car too harsh and cause a lot more wear and tear on the car also . Especially as the roads are so rough generally.
Also the kW coilovers seem to be a very popular setup for racers in the Aus Tarmac series.
After heaps of research and talking to very experienced racers in who are commited to Tarmac I will be going a similar setup to the kW but the budget is the only issue lol.

Keep them coming this looks pretty sweet.

http://shop.keislerautomation.com/Mazda ... -20876.htm

front and back, saves a kilo or two, have emailed them for more details and it looks
they have Started a K Swap as well.

I spoke with Josh from MCA thay are always honest and indicated the Gold Series would be of minor benefit over the RED Series which is only $2600.

That Inboard Suspension at the rear is interesting should solve the lack of travel issues.


I like the MCA Hammerhead but it's not really a car any more it's more of a very sound science experiment,
that they build up around super soft 295 all round rubber it's just not relevant for the MX5 platform.

Yeah, I was going to suggest look at the mca reds.


The push rod assembly above is pretty interesting. It's something I first thought about when I got my car. There are a lot of advantages to it but it's still added complexity.

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Mca reds would be ok but in my opinion I would opt for something with separate adjusters for both rebound and compression, other wise it's just a gamble as to weather the valving is the right spec for ur application. If it's not that means sending the suspension back to have the shim stack adjusted. At least with separate adjusters you can tune the shock more accurately. Unfortunately it's not one size fits all

To have separate adjustment you need either a twin tube shock or external canisters. I've been told mca can add external canisters to the reds.

I wasn't just talking about the hammerhead, the two evos run MCA golds as well along with a lot of the other competitors.


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My normal questions, what is your budget and how are you going to measure improvements?

Make a plan, change one aspect, test & analysis then make more changes or introduce another change. There are some really good books on this subject, competitor car aerodynamics & competition car data logging (Simon McBeath) and Race & Trackday Driving Techniques (David Hornsey). Or have a read of this http://www.jameshakewill.com/sus-pos-v1.pdf

It takes horsepower to overcome drag, drag causes downforce. Have you calculated your drag coefficients? This will help you produce the most downforce for the HP you have. It is a fine balancing act with aero and low horsepower cars.

I would say MCA reds with external canisters (this is what I am considering when the BC's need replacing as this gives you separate bump and rebound settings. However until you sort out the rest of the suspension you may not know the spring rates you require.

Have you thought alignment settings? Maybe consider adjustable camber arms to get more than -3 deg camber. This will also depend on the tyres you will be running.

If you can please post what your ultimate goal will be, full slicks 200 RWHP or DRZ03's 150 RWHP for example.

K swap - 150whp is only the beginning

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Over the top options:
http://aeromotions.com/products/s2-dynamic

Keith Tanner (of FM fame) has documented his Targa Miata rally build, possibly using FM's Afco brand suspension.

I think there is a Canberra based MX-5 rally nut and forum member 'Russellb', who might be able to advise on proven solutions, too.

www.targamiata.com
viewtopic.php?f=68&t=43832


Rally driving - aka playing in the mud while breaking expensive toys, what's not to like? :-)

Nick.

I'm not sure the Keisler uprights are going to be of much help in rally application.

The design goal of those is correct roll center's on really slammed track setup and they start with 3 degrees of camber and more through normal suspension adjustment.

I suspect in a rally application you will be ramming a wheel into the chassis or bottoming the shocks before the bump stops do their thing.

From my research into these, typically for a 2.5 in drop over factory, 1in is by the springs and 1.5 by the uprights.

At these low ride heights, interference between the rear axle and rear suspension coils is something to look out for.

Andrew Keisler is very help though.

Those parts are barely out of prototype stage, however, and only tested applications are for low track vehicles.

Having a K24 powered MX-5 shows you are a bleeding edge racer, well beyond anything I can advise on.

Let us know how your build goes.


Nick.