Re: Race Spec Roll Bars in Street Cars with Convertible Tops

["N" <twobees@xxxxxxxxxxx>]

Derek:

In answer to your comments:

>  - the needs of racing and "street" rollbars are slightly different. With
a proper racing
> harness the driver is effectively immobile and can't even lower his
helmeted head to one side to
> avoid a broken neck or crushed vertebrae in a rollover.  With a normal
street 3-point harness
> there is at least some freedom for the head to moved to one side in same
situation. Therefore an
> effective race rollbar needs to be 3-4" higher than an acceptable, "better
than nothing" street
> bar. Even your excellent rollbar, teched by SVRA etc or not, doesn't
really provide this
> protection.


Actually, the roll bar IS 3 - 4" over my head, 2" with helmet on.  AND, I
use a 5-point harness on the street as well as on the track.


>  - if you are so concerned about accident protection on the street - don't
drive any open car -
> or even any "old" car.


Concern need not mean paranoia.  I drive my MGB about 8,000 miles a year
now.  Used to be more.  I practice defensive driving to the point of running
headlights ALL THE TIME (Highbeams in Westport, CT - the air-head,
soccer-mom, SUV capitol of the East.).  AND, have you ever seen the results
of MGB crash tests?  I have.  They were impressive.  Granted that age & rust
weaken the body structures.  But, it is a realatively safe small car.


>  - question - since you took such obvious pains to maximize the height of
your rollbar within
> the confines of the soft top why did you not curved the top bar to follow
the curvature of the
> soft top - thus gaining another inch or two in center height?


I was lucky enough to find someone who would deal with the SCCA specs AND my
need to use a top in building a roll bar.  I wanted that.  But, the extra
difficulty of what you suggest was beyond what the builder would do.

Norm Sippel
'66 MGB, et al

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