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I am have just bought a Brown Davis roll bar which weighs about 18kg?? I just spoke to a friend of mine who bought a BD stainless steel polished roll bar 10 years ago which weights only 3-4kg. Is there a lightweight BD roll bar which I may not know about ?

I believe you can get an alloy roll bar which costs more and of course weighs less.

Most people will though have the standard steel roll bar.

Maybe someone else can confirm this as i dont have a BD roll bar myself.

I think that was polished alloy, not stainless steel.

18kg seems high, I don't remember it being that heavy, but it was a while ago and the memory fades ...

But there are no lightweight steel rollbars, and if you think about it you will realise why

I have a polished alloy BD bar. It would only be about 3kg or so.

I don't think it is CAMS approved like the steel ones though...?

18kg for the powder-coated steel BD rollbar sounds about right to me. I've had the bastard in and out of my car a few times now.

zossy1 wrote:I have a polished alloy BD bar. It would only be about 3kg or so.

I don't think it is CAMS approved like the steel ones though...?

I am not a fan of over-engineering especially when it comes to adding more weight to a light weight Sports car. I can see why you would need a heavy duty roll bar but if results can show that a lighter material is just as strong then I will am prepared to pay a premium for the lighter and nearly as strong option. Keeping in mind how many tenths of thousands of dollars porsche charge for something that is 55kg lighter.

The heavier roll bar could help balance the MX a bit more by shifting more weight to the back ???

zossy1 wrote:I have a polished alloy BD bar. It would only be about 3kg or so.

I don't think it is CAMS approved like the steel ones though...?

My first BD was alloy, and it was light. And looked very nice.

But, if CAMS says you need a roll bar, it needs to be steel, as alloy is no longer allowed (unless you have an old one in a car with the necessary documentation).

I am thinking of cutting mine down to a single hoop so it only protects the driver and the passenger can die.

That way it will be about the same weight as the aluminum roll bar but I still get all the protection I need.

BD may be able to do one in chromoly but it will be expensive. I would expect that you would be looking a real weight saving maybe 50%.

wun911 wrote:I am thinking of cutting mine down to a single hoop so it only protects the driver and the passenger can die.

That way it will be about the same weight as the aluminum roll bar but I still get all the protection I need.

I like the single hoop look as well, im surprised no one makes one for the mx5, i was admiring a lotus 30 the other day at West Gosford getting some work done on it that had a very nice single hoop bar and thinking just that.

Just got my frog chassis frame rails, BD roll bar and Sparco seat installed by Motorsports Essentials. It really amazes me how reasonably priced Dean charges…really MX5 type prices. One time I went there to service my MX5 and I came back with more money then before the service. It seems like Dean really knows the MX5 inside out. I am I giving him free publicity…hell yes especially after all the good work which he has done and for the price he has done it for.

I will post feedback on whether the roll bar, seats and frame rails did anything to improve my driving enjoyment.

Just went for a night blast after chassis rail, BD roll bar and Sparco seat was installed. wow...all I can say is I did not know the MX5 can feel so different with mods. The biggest difference seems to be the improved ride comfort over bumps as the suspension seem to be absorbing the bumps more effectively. I get more of the german can thump over bumps rather than feel the car creaking. Its just that much closer in chassis rigidity compared to a non convertible.

The only problem is I can't isolate the effect to the BD bar or the chassis rail as both were installed at the same time. I reckon it would be 50:50.

As for the Sparco race seats, it was a laugh out loud ridiculous initially in getting in and out but after a few times you do get used to it. It also feels a bit strange sitting in it initially but like others have said it is surprisingly more comfortable compared to the stock seats...it must be the support. The seats just add that bit more to the driving enjoyment as I felt tightly held in during corners...you can feel corners better and seem to have a better sense of what the car is doing.

I took out my spare wheel to make up for the weight of the roll bar. : )

All in all, I feel it was money well spent as it does help me enjoy the car and the drive quite a bit more. Roll bar also does add a bit more masculinity to the car.

Below are mods I have made which is ranked from most perceived difference to the least.

1. T&C Exhaust and Cat system
2. Install NB8B chassis brace under the car.
3. Frame rails and BD roll bar
4. Tokico Sports Suspension and Springs
5. Sparco Sprint Seat
6. DDM CAI (can't seem to feel any difference with this install).

Happy driving guys. I reckon the chassis stiffening mods should not be an optional upgrade for any NA and NB as it adds so much more solidity to the car. You'll definately notice the difference around bends and corrugated roads.

I had a few more drives after the chassis frame rails and BD roll bar install. Wow..I am starting to understand how some people actually shared about the ability to focus more on the bonnet and the front of the car now during hard cornering. It just seems like your driving vision is less blury because you jiggle less over corrugations and corners.

The other thing I noticed was that I could now dial down my Tokicos to 3 which was too uncomfortable before the chassis and roll bar install. As a result the car feels so much more planted over fast tight corners as there is much less floaty bouncy feeling.

All in all, I have to say that Mazda really did nearly go all the way with optimising the handling. I am quite literally shocked at how much improvement i am experiencing from a few simple mods. The MX5 has a great DNA in low center of gravity and 50:50 weight distribution so it is amazing what you can build on.

Like most people who have tightened their chassis, I would say spend the $1500 to improve the rigidity of your chassis and the benefits to ride, handling and comfort will astound you. Don't worry about the extra weight as you won't feel it. Its amazing how shity the NB felt when I first bought it...felt like a piece of rattly annoying tin can...now it feels like a 911 coupe ! My NA definately felt more buckled down compared to my 99 NB.

For me, I'd say the improvement was 80% butterfly brace, 20% roll bar.