Jack, Norm, Derek, et al.;
Derek mentioned forming the roll bar to the contours of the hoops on the
MGG stow-a-way top. Norm suggested the roll bar manufacturerer
apparently felt it was "beyond the scope" (my words not his). My
question is this. Is the ingegrity of the main hoop on a roll bar
compromised by adding the bend that would require to match the contour
of the MGB stow-a-way top?
Larry Hoy
>-----Original Message-----
>From: owner-vintage-race@autox.team.net
>[mailto:owner-vintage-race@autox.team.net] On Behalf Of
>JWoesvra@aol.com
>Sent: Sunday, July 08, 2001 8:15 AM
>To: derek.lola@home.com; twobees@sprynet.com
>Cc: vintage-race-digest@autox.team.net; mgs@autox.team.net;
>italian-cars@digest.net; bmw-digest@digest.net;
>alfa-digest@digest.net; alfaromeo750-101@egroups.com
>Subject: Re: Race Spec Roll Bars in Street Cars with Convertible Tops
>
>
>In a message dated 7/7/01 8:53:50 PM Pacific Daylight Time,
>derek.lola@home.com writes:
>
>I have a few comments on the subject of tech and roll bars. I
>hear things
>from time to time about what we accept, etc. Ten of so years ago I put
>together a "roll bar specification" sheet that was based on
>the 1972 SCCA
>GCR. It mainly deals with tube specifications and wall
>thickness required for
>various car weights. There are some recommended practices and
>brace angles.
>We still send this sheet to anyone who wants it. However, the
>stock car guys
>who populate almost any community nowdays know all of this and
>much more. At
>tech we look for a sound structure that is firmly attached to
>the car in
>whatever way is appropriate for that kind of car. The correct
>system varies
>vastly from model to model. I give free reign to our
>inspectors to use good
>judgement in this area. If they find something that they don't
>like, we will
>discuss it with the racer and recommend changes.
>
>My point is this: whether a roll bar/cage system meets some printed
>"guideline" is irrelevent. It must only meet the satisfaction
>of a particular
>tech inspector on a given day. Sometimes when things are busy
>a roll bar may
>be checked off without a second thought. We have found serious
>flaws in roll
>bars that have "passed" many previous tech inspections at
>numerous good
>organizations. Don't count of tech to uncover every unsafe
>situation in your
>car.
>
>Another misconception concerns the number of mounting
>"points". We have no
>rule printed or implied that limits the number of points. I
>hear 4 points, 6
>points or whatever. This is a bunch of BS. If it tkes 10
>points to build a
>safe bar system in to your car, then that is what I want to
>see, 10 points!
>
>It is quite possible to have a very safe main hoop with good
>bracing, a seat
>mounting structure and good side intrusion protection without
>changing the
>outward appearance of the car. The intent is a key factor. We
>can usually
>tell if a system is intended for driver protection or an
>attempt to enhance
>performance through stiffining. Again this is quite subjective
>and older cars
>may have different standards than the newer ones.
>
>Jack Woehrle
>SVRA Technical Director
>
>
><<Even your excellent rollbar, teched by SVRA etc or not,
>doesn't really
>provide this
> protection.>>
>
> <<if you are so concerned about accident protection on the
>street - don't
>drive any open car -
> or even any "old" car.>>
>
> <<This car, as many know, is my year-round daily driver and
> > occasional vintage racer. The roll bar has passed tech for
>SVRA, HSR & > VSCCA.
|