I agree with Kelvin entirely, but if you autocross and want good belts to
keep you still, they will not let you use them if you don't have a rollbar
to protect you.
James Nazarian
'71 B roadster
'71 BGT rust free and burnt orange
'63 Buick 215
On Wed, 29 Mar 2000, Dodd, Kelvin wrote:
> Michael:
>
> Sorry to jump in on this, but this question went around the list a
> while ago.
>
> A roll bar will only protect a person if their body stays within the
> limited area defined by the height and shape of the hoop. In a race car the
> body is strapped securely to a seat and the head is protected by a helmet.
> The race course is carefully managed to reduce the possibility of intrusion
> into this protected area during a crash. Haybales, tires, armco etc.
>
> For street use a roll bar is going to give limited protection in the
> case of a roll over. To fit under a soft top, the bar tends to be low.
> Stock seat belts do not hold the body firmly in the seat, and the head is
> not protected if it impacts the bar. Luckily unlike an SUV (I couldn't help
> myself) it is difficult to roll a sports car. Unfortunately the kind of
> impact that involves a rollover tends to also involve lumpy bits that can
> intrude into the area protected by the bar.
>
> Roll bars do provide some side intrusion protection, so there is an
> added element of safety in the more prevalent case of a T bone accident by
> some idiot that did not see you.
>
> All in all, installing a roll bar in a street car is a very personal
> decision. The likelyhood that a rollbar in a street car will save your life
> IMVHO is small. Once a sports car starts to roll, the fates have you in
> their grasp. See Barneys pictures of Dick Criswell's fatal crash. A roll
> bar would not have helped Dick. Driving skill and good seat belts are the
> best way to stay safe.
>
> As to the initial question. All of the commercially available roll
> bars if installed correctly will keep the car off your head in the event of
> a rollover on a solid surface. The question is, what were you doing rolling
> over on a solid surface :)
>
>
> Kelvin.
> Who has a roll bar in his MGB GT, and Vintage race car. But does not plan
> to put one in his MGB V8 street car.
>
> > -----Original Message-----
> > From: Michael Torrusio [mailto:mtorrusi@maine.rr.com]
> > Sent: Wednesday, March 29, 2000 3:56 PM
> > To: Eric
> > Cc: MG CHAT LIST
> > Subject: Roll bars
> > Importance: High
> >
> >
> > Eric;
> > Does this mean that the of-the-shelf roll bars won't do a
> > good job if we
> > roll over during standard driving? (Assuming there is such a
> > thing as a
> > standard rollover. And, if one gets a custom made roll
> > bar,what's your
> > protection if you bring it down to half size as you mentioned
> > you would do
> > for regular driving. And, lastly, there seems to be a bit of
> > talk in this
> > group about racing. How do I find out about it? I'm in
> > Portland ME. And
> > someone mentioned pylon racing. Any info about this?
> > Thanks.
> > --
> > Michael Torrusio, Jr.
> > USCG Master
> > Seven Seas Yacht Delivery
> > 443 253-0200
> >
> > ----------
> > >From: Eric <eric@erickson.on.net>
> > >To: Michael Torrusio <mtorrusi@maine.rr.com>
> > >Subject: Re: Bodily Dimensions
> > >Date: Wed, Mar 29, 2000, 10:10 PM
> > >
> >
> > > Michael Torrusio wrote:
> > >>
> > >> Question:
> > >> We are going to get a roll bar for our 71B. Is there any
> > reason why
> > >> you are having one built rather than getting one through say, Moss?
> > >
> > >> >
> > >> > I have a person who is building me a rollbar (yes,
> > finally) and he
> > >> > would like to get materials and some construction happening
> > >> > before this weekend when I can give him my car for a few
> > hours for
> > >> > the final fitting.
> > >> >
> > >
> > >
> > > Michael,
> > >
> > > Yep, it is a racing thing. The main reason is because I
> > want the top of
> > > my head to stay where it is and because I race my car and our rules
> > > state that the rollbar needs to be more than 50mm above the driver's
> > > head (to stop you losing the top of your head or breaking
> > your neck if
> > > you turn turtle).
> > >
> > > Most 'off the shelf' rollbars don't conform to this -
> > especially if you
> > > are wearing a helmet.
> > >
> > > The other requirements are that there needs to be a diagonal
> > > crossmember, or a "tranverse tube between a top corner of the main
> > > rollbar and a lower mounting point on the other side of the
> > rollbar",
> > > plus, for further strength I will have two "backstays".
> > >
> > > As you see... not the usual "off the shelf" rollbar and one
> > which will
> > > probably prevent me from putting the roof up (unless I can find some
> > > ingenious modification to either the roof/frame or rollbar
> > which fits
> > > all requirements). I can make the rollbar (half cage)
> > 'removable' to
> > > return it to a 'roofed' vehicle for 'normal' driving.
> > >
> > >
> > > Eric
> > > '68MGB MkII
> >
>
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