Re: Removable Spider Roll bars

["George Schweikle" <schweikg@domain.elided>]

Digesti,

I need to upgrade the rollbar in my autocross Spider, and have been
following the recent discussions. Here's my two cents worth:

In light of use for AROC and SCCA Solo II events, the rules from these
organizations must be considered. Russ Neeley is the AROC Competition
Chairman, and an SCCA race scrutineer, and will surely chime in with his
comments.

I believe the hoop must be continuous, so a "legality bump" such as I have
on my car is not acceptable regardless of how sturdy it's construction. My
memory of an Autopower bar purchased for my old 1750 spider is that the base
mounting bolts ran through the package sill area, then through reinforcing
plates plate under the car (this was to wrap the bar mounting around a
section of unibody construction, rather than just to the top). My current
car has a bar that bolts to tapped plates welded on the top of the sills.
I'm thinking the base must be "through bolted", not into a top mounted plate
(regardless of how sturdy it's construction), but this may not be correct..
Comments?.

 I, too, want a street/track bar and have wondered how to address the helmet
clearance requirement issue. While rules seem to mandate a continuous hoop
mounted on the frame/body, I wonder if a (top-clearing) shorter removable
hoop could be mounted in upright tubes, and then raised when needed with
spacers that would slide into the bottom of the uprights. These would need
to be solidly made, and as strong in vertical strength as a hoop butting on
the frame/body.

Once these mounting and height varying issues are settled, the diagonal and
lengthwise braces could be made removable through bolts or "Pip Pins". To
Brian Shorey's point, the rearward extensions would have to be attached to
the bar, not the uprights.

If a design could be established, there may be enough potential customers
for Biba to make a small run of these bars. How many would be needed?.

Hey Russ, help us out here with mounting and design requirements...

George Schweikle
Lexington, KY
'76 Spider

(snip)
> My question, is there any interest in this, realizing at the outset it
> would be perhaps more expensive than purchasing both an Autopower street
> and track set of rollbars? The positive being one can have the
> advantages of both (and more) and be able to switch quickly from one to
> the other.
>
> It's more a feeler to see how much you Spider People who use, or
> contemplate using your cars for both street & track, are concerned with
> these issues...and are willing to pay a reasonable amount to protect the
> top two to four inches or so of your head.
>
> Biba
> Irwindale, CA USA

> From: "Brian Shorey" <bshorey@domain.elided>
> Subject: RE: Removable rollbar, etc.
>
> <snip>
> > My solution would differ somewhat from Brian's in that the removable
> > down / cross brace to the passenger side would not allow for a passenger
> > to be present. So, on the street, it (probably) would not be installed.
>
> Fwiw, there's really no reason to make a passenger not fit when the
fore/aft
> brace is installed.  It's simply a matter of planting the base in the
right
> position.  Also, keep in mind that for some track events, you *must* take
an
> instructor with you.  This is more prevalent in lower skilled TT type
> events, which is where you might expect to find somebody with a rollbar
like
> this one (as opposed to a full cage in a race car).
>
> I also figured that on the street I'd remove the entire thing and run with
a
> street height bar (or none at all), which would allow for the use of the
> top.
>
> Hmmm, if you're thinking of a system where the height of the main hoop is
> adjustable (which would alleviate the need for a street and a race height
> bar), don't bother.  In most, if not all, racing organizations I'm
familiar
> with the tubing of the main hoop can *not* be interrupted.  It must be a
> single piece.
>
> Also, in an adjustable system (I have seen one), if you raise the height
of
> the main hoop you change the place where the pads on the rear extensions
> come to rest.
>
> bs

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