what size tubing for down bars on cage?
 

Hi everyone, I was thinking of adding down bars to my mild steel 10 point cage. The bars would go from the vertical door pilar bar through the fire wall and down to my stock sub frame. My car currentley runs 10.0x times. The cage is constructed of 1 5/8 x .134 wall tube . I would like to use 1 1/2 x .120 wall tube for the down bars, do the down bar tubes need to be 1 5/8 x .134 wall tube to get an 8.50 cert on the chassis? Please help - Al

Do the down bar tubes need to be 1 5/8 x .134 wall tube to get an 8.50 cert on the chassis?

you need to hit the rule book for that.

My NHRA rule book does not address those bars and I believe the down bars are addressed in an SFI spec which I do not have that is why I am asking her - Thanks Al

Im not 100%, but I dont belive anyone cares wether or not you even have those bars yet aloone what size they are. When I had my 25.4 cage certed,7.50, all they looked at was the interior CAGE bars.

Craig

Craig, Thank you for the reply :wink:

He is right the only bars that they are concerned with are the bars around you, the bars behind roll bar and in front of firewall are not even in spec book

Agree forward bars are only stiffing bars, nothing to do with the chassis certs., if you are goining to a strut front end then i would use 1 5/8' if it just structial anything works.

JMO

Zip.