strut braces

[AJ]

i'd call it a draw myself

[Okibi]

Nahh don't turn it into some sort of competition.

I really appreciate CT's thoughts as he's got a wealth of knowledge and experience.

I'm just trying to interpret the results i've had and draw a technical conclusion.

[Gilly71]

To add another point of view...

To demonstrate the point (crudely), assume for a moment that your car has no suspension at all only a fixed chassis (like a go-cart if you like). When you corner your chassis will flex, particularly between the two front wheels, two rear wheels and between both front and rear axles. Too much flex can be conterproductive to mechanical grip as the chassis is absorbing energy that would otherwise be directed as weight (read grip) on the tyres. Remember that grip is affected largely by the amount of weight (or force) applied perpendicularly to the contact surfaces.

Stiffening particularly the front and rear axle lines independantly can help 'tune in' high speed grip as CT and Okibi have described.

Adding back our suspension and variable steering geometry we can now more reliablely tune the finer characteristics of our cars though suspension tuning, without being limited by chassis flex which can limit the extent to which we can create additional grip in particular. Of course you can go too far, by having a rock steady chassis and very hard suspension settings, that will be determental to grip as the car is easily upset by the smallest of bumps because both the chassis and suspension are reflecting all the energy rather than effectively absorbing any.

Generally road cars, particularly convertibles can always do with some extra chassis stiffening, as the manufacturers are often limited by weight and material costs initially. Mazda has been able to gradually improve chassis stiffeness over each successive model by improving design and materials. The latest NC is 50% more torsional rigid (between the axles) than the NB8C and probably double that over the early NA's.

The thing to point out here I feel is that generally stiffening will be beneficial to overall handling but care needs to be taken to re adjust suspension and alignment settings to make the most improvement.

I've noticed significant diffence in increased understeer with the front strut tower removed, and after fitting the Racing beat type II bar I noticed reduced scuttle shake going over bumps.

Hope this provides a more simplistic explaination for the non tech heads..
(Sorry Okibi /CT I hope I'm not too far off the mark, I know Ive left a lot of detail out)

[Okibi]

I’m more a bumbling fool than a tech head.

I just wish I had the technical expressions to simplify my explanation regarding the change in characteristics I felt with the addition of the strut brace to our stock NB8A .

[AJ]

bumbling fool be buggered!!.......you're the translator between the full on tech heads & us plebs Okibi

[JBT]

Well, I've got a strut/tower/shock/whateveruwantocallit brace fitted to my car and I'm leaving it there. Sorry, but I'm damned if I could notice any difference once it went on though.

[Ted]

Never noticed any handling difference in the upper brace (engine bay) other than making it harder to adjust the shocks and pull plugs/leads out. Unfortunately, unlike McPherson struts, double A-arms apply the inwards forces differently and lower down. The top brace can still reduce flex for corrugations etc.

The underbody braces though are very different, nothing like an MX5 chassis and PPF totally braced all the way out to the sills. Easiest shown in jacking up one corner of the MX5, and try that on different year models. The later cars are extremely rigid out of the box.

[smiles]

WHOA what a difference.
I just fitted the front and rear under body braces and it's made a huge improvement. There's a significant reduction is body shake and it just feels more stable.
I've also found it feels like it's more prone to oversteer (perhaps I was just having too much fun!) now, could this be right? The steering feels better, the whole car feels better.

Thanks for the advice guys, I think I'll stick with this level for the time being, bang for buck I'm quite impressed. I think it may have even reduced the size of the hole in the ozone, it's that good!

Thanks again.
Ian

[Babalouie]

I've also found it feels like it's more prone to oversteer (perhaps I was just having too much fun!) now, could this be right? The steering feels better, the whole car feels better.

Thanks for the advice guys, I think I'll stick with this level for the time being, bang for buck I'm quite impressed. I think it may have even reduced the size of the hole in the ozone, it's that good!

I think (as CT has said) the braces don't affect how the rubber meets the road, but it would reduce the body twist and therefore give a sensation that the car is more responsive.

But I had the same impression when I fitted the Brown Davis, the car was definitely more taily.