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Why do you have a rollbar? Road or track?
Posted: Fri Jun 19, 2015 5:00 pm
by madkeen
Hi folks. I don't track my NA8 but I have been wondering if I should get a proper roll bar (not one of those cheap stylebars that offer no safety.) I see quite a few MX5's on here, if not out on the road, with roll-bars intact, and wonder if people only get them because you go on track?
Would you get one for a road only car?
I know they technically make the car safer, but they areexpensive and I think they really ruin the shape of the car. Seem so heavy-handed on a sweet little NA.
Interested to hear opinions.
Thanks
Re: Why do you have a rollbar? Road or track?
Posted: Fri Jun 19, 2015 5:18 pm
by KevGoat
If the roll bar was no longer intact, I doubt you'd be seeing the car on road
I'm of differing opinion in that I reckon a roll bar can enhance the look. I had a BD bar in my NA and the change in the feel of the car was quite discernible. Less shake and just felt more solid. Does cut down on using the back shelf a little, but then so do the wind deflectors as well. I don't go on the track, road only car and yes, I will fit one to my SE eventually.
Re: Why do you have a rollbar? Road or track?
Posted: Fri Jun 19, 2015 5:30 pm
by Lokiel
I think the MX5 Plus Twin-Hoop roll bars suit our cars beautifully.
Not only are they a safety feature in the case of rollover, but the MX5 Plus roll bars with their in-built torque box really stiffen up the chassis. There's quite a lot of debate on this but I'm a firm believer after getting one fitted to my SE which has the stiffest factory bracing of any NA/NB - it was still quite noticeable.
NA/NBs don't have much bracing to prevent chassi-twist - the MX5 Plus roll bar really helps eliminate this.
Re: Why do you have a rollbar? Road or track?
Posted: Fri Jun 19, 2015 5:35 pm
by madkeen
Interesting feedback guys. Thanks. Keep it coming

I think my aversion to the look of rollbars is in part because I have an LE with cream seats. When you have black seats, black roll bars tend to blend in not so bad.
I agree the AutoPlus twin hoops are best suited. Maybe I can look into twin hoop chrome bars (if they exist) to sit better against my cream seats! Hmmmm
Re: Why do you have a rollbar? Road or track?
Posted: Fri Jun 19, 2015 5:47 pm
by lee
I've got a BD bar in mine for a few reasons
-Safety; it's a fair bit stronger than my spine is, so should the car find itself wheels side up, i'll probably end up with a compressed spine rather than complete decapitation. Also acts as a strong transverse brace between the seatbelt towers which should prevent crumpling in the event of a T-bone crash. I've been in a car on the vertical line of the T during a T bone crash, and a strong B pillar is the only reason the other dude lived.
-Aesthetics; i love the look of the car with the BD bar in. It kinda makes it look a little like a targa top
-Functionality; I can hang my bike from it, and I strap my ProjectG Bikini top over it.
-Price; i got mine on a sale, I paid less for it new than I've seen them go second hand.
Re: Why do you have a rollbar? Road or track?
Posted: Fri Jun 19, 2015 5:53 pm
by manga_blue
An NA8 should already have a factory brace across behind the back seats to stiffen it up. A B&D rollbar just replaces that and makes no noticeable change. I can't imagine how any other shaped piece of steel across the same span would be any different but you never know.
Re: Why do you have a rollbar? Road or track?
Posted: Fri Jun 19, 2015 7:01 pm
by Magpie
Mine is for looks.
Re: Why do you have a rollbar? Road or track?
Posted: Fri Jun 19, 2015 8:42 pm
by Snowmotion
My MX5 Plus Single hoop torque box was for mostly safety but a bit of looks.
I like to look of them and at 6'3" I needed one that would not limit seat travel.
It gives me a good secure feeling in the car.
Re: Why do you have a rollbar? Road or track?
Posted: Fri Jun 19, 2015 8:48 pm
by Jeo
Magpie wrote:Mine is for looks.
Beat me to it Magpie. Harkparking for the win.
Re: Why do you have a rollbar? Road or track?
Posted: Fri Jun 19, 2015 10:44 pm
by Nevyn72
madkeen wrote:I know they technically make the car safer, but they are expensive and I think they really ruin the shape of the car.
Yeah, I have to agree entirely!
I mean look at this image to see how the Automotive+ twin hoop absolutely ruined the shape of my car......

Re: Why do you have a rollbar? Road or track?
Posted: Fri Jun 19, 2015 11:06 pm
by davekmoore
BD one on mine. It will be staying because the car is tracked. Compared with the previous NB8a and NA6 cars, this one is waaaay stiffer. Dunno whether this is the roll bar or the extra bracing on an SE. Of course, it's also much heavier, so doesn't stop or corner or accelerate as well as some other cars at the track. Some track cars have even had a general stiffening-ectomy to reduce their weight and apparently to allow some chassis flex. These do tend to have rollover protection inside them though, in some cases full cages, which might reduce the need for other stiffening.
Re: Why do you have a rollbar? Road or track?
Posted: Sat Jun 20, 2015 12:05 am
by madkeen
Thanks for your thoughts everyone.
Ha! Fair call Nevyn72. I stiiiiiiiiilll think your car would look nicer without it, but hey, that design is 1000% more pleasing to my eyeballs than the ones with the crossing bars or Brown Davis). Like the chrome too! I think you just put a dent in my savings....
Re: Why do you have a rollbar? Road or track?
Posted: Sat Jun 20, 2015 8:16 am
by lightyear
I still don't understand how people can feel the chassis being stiffer from installing a roll bar. Look at the car properly with the roof down and doors open. Now imagine how it is stiffening the chassis.
A hardtop is the common mod to brace the car.
For a road car, I don't think you need one. The percentage of MX5's flipped on the road would be tiny. Even on the track, the percentage would be so small. Spend your money on maintenance.
Re: Why do you have a rollbar? Road or track?
Posted: Sat Jun 20, 2015 9:24 am
by StillIC
lightyear wrote:I still don't understand how people can feel the chassis being stiffer from installing a roll bar. Look at the car properly with the roof down and doors open. Now imagine how it is stiffening the chassis.
A hardtop is the common mod to brace the car.
For a road car, I don't think you need one. The percentage of MX5's flipped on the road would be tiny. Even on the track, the percentage would be so small. Spend your money on maintenance.
Thanks Lightyear, I am glad someone here sees past the traffic.
I have an AGI roll cage for use on the track (which I highly recommend), but if my car were a road car only it would be gonski, although I would install the NA8 tower brace if I didn't have something there.
When I was between cages (BD to AGI), driving on the road without the cage felt liberating. And the chassis felt just as stiff (i.e. not stiff!) as when the cage was/is in place. But without the cage I could see out the window more easily, adjust my seat to where it was comfortable, throw my jacket on the parcel shelf, not bump my head on anything, put the roof up and down from inside the car, unzip the window without cracking my neck, access the fuel tank without spending a weekend dismantling and mantling, and generally enjoy life to the fullest!
Having a cage brings many disadvantages but only one advantage for some of us. If only the MX5 seat backs were taller.......
Re: Why do you have a rollbar? Road or track?
Posted: Sat Jun 20, 2015 10:42 am
by Lokiel
lightyear wrote:I still don't understand how people can feel the chassis being stiffer from installing a roll bar. Look at the car properly with the roof down and doors open. Now imagine how it is stiffening the chassis.
A hardtop is the common mod to brace the car.
:
The seatbelt towers provide structural rigidity but are basically a U-shaped brace so the tops can twist in opposite directions.
Put a brace across them, such as the meaty torque box built into the MX5 Plus roll bar, and this twist is reduced significantly (imagine two fence posts; add a beam across the top and it's much harder to "wobble" them from the top).
In an NA/NB, this brace is essentially the only significant horizontal brace above the floorplan (the NC has much better chassis stiffening - it was recognised as a deficiency in the NA/NB).
The hardtop is definitely NOT a brace.
PS: I've never drĂven around with the doors wide open so cannot verify that the rollbar makes a difference with/without the doors wide open.