Re: Racer's new Rollcage

[Richard Welty <rwelty@domain.elided>]

At 11:39 AM 5/21/99 -0600, Tom Mandera wrote:
>Seems like a better deal than $150 for a GUS rollbar and $100 for a
>Smitty front 'cage plus $5.61 a foot to add FOUR door bars (upper n'
>lower), a backbar, the two seat mounts, and extend the rear legs (about
>50' of tube total).. and they fish-mouth all of the joints n'
>everything!

sounds like a better cage.

here are some comments from my experience (i am the divisional
administrator of tech inspection for the northeast division of the sports
car club of america, and have logbooked quite a few new race cars in my
life, done a lot of full inspections of existing race cars, done post
accident workups on a lot of wrecks, and have built my own Improved Touring
Alfa Romeo Sedan.)

if there is much side impact going on, consider the following:

1) NASCAR style door bars, where you have multiple lateral tubes, small
vertical tubes joining the lateral tubes to create a grid, and the door
bars are angled outwards front and back to create a couple of inches of
additional space to the left of the driver. this may entail gutting the
driver door to some extent.

2) a "shin bar" under the dash, from the left to the right sides. this will
provide meaningful stiffening in the event of a side impact where someone
t-bones you in the A-pillar area.

if you get much front quarter banking, then short bars going forward from
the front braces to the outside of the footwell can provide meaningful foot
protection. in heavy impacts of our admittedly lighter race cars with
armco, i've seen footwells move quite some distance.

a petty bar, which starts at the top of the main hoop next to the driver's
head and goes diagonally to meet the cage in the front of the passenger
foot well is a very effective cage stiffener.

are either of these cages DOM tubing? DOM will generally be more expensive,
but will provide greater strength for a given weight that the more common ERW.

richard