chassis tube sizes

[hotrodharley]

i've decided to remove steel floor pan and go all aluminum on floor;;i have 2"x3" boxed frame rails.14 point cage with some added bars of my own;;funny car cage added..i'm using m/s tubing on this build.i want to ceterify to 7;50's if possible;
i belive i need "x" bars between the frame rails[under trans tunnel area and a tube running diagonal from frame rails[2"x3" boxed]to rocker panels
what size would these bars need to be?do i need them?

[hotrodharley]

here is pics of tubes i'm asking about[goes under floor pan]

IMG]http://i142.photobucket.com/albums/r108/outlaw427/rickwood/05-30-08025.jpg[/IMG]

http://s142.photobucket.com/albums/r108/outlaw427/rickwood/?action=view&current=05-30-08025.jpg

[sg1586]

Can't do aluminum on the drivers floor. That Won't pass tech for sure!!

[hotrodharley]

Can't do aluminum on the drivers floor. That Won't pass tech for sure!!

meant to say i'm doing the center sec[between my frame rails]in aluminum with aluminum trans tunnel[with dutz fasterners for easy remove]the floor from frame rail and rocker pannel doing in 14ga. metal

[zipper06]

I don't think you need them to certify to 8.50, but to certify to 7.50, my 41 willys alston tube chassis B/P shows 1 1/4" X .118min. size, you also donot need a funny car style cage to certify to 8.50.
The 2008 rule book does not address this situation, but you are probably already aware of this.
I will install them on my Anglia rec. tube chassis built by A.R.T., but i only want it to certify to 8.50.
I know it's an addition expence, but the only way to know for sure is to buy the SFI 25.2 specs. or talk to an NHRA, tech if there's one in your immediate area. I'm lucky i have one about 40 miles away from me.
I'm sure someone of the chassis builders will come on here and shed some light on this subject, it was also addressed about a year ago here on this forum but i donot recall the real answer (old age :oops: )

Zip.

[hotrodharley]

thanks everyone for the help;;i had bruce willams e-mail the drawings and sizes i need for the tubes..now just got to order tubing and weld them in.my closes nhra inspector is 360 miles away so hoping to have all my i's dotted before hauling car that far.

[hotrodharley]

thanks everyone for the help;;i had bruce willams e-mail the drawings and sizes i need for the tubes..now just got to order tubing and weld them in.my closes nhra inspector is 360 miles away so hoping to have all my i's dotted before hauling car that far.

bruce willams or who ever else would have this information and pics could you give them to me again..my putter crashed and burned and i lost all e-mails and pics so i'm back to square one again.these tubes i need sizes and pics of is the "x" bars between the box frame rails from the trans cross member to the ladder bar cross member;;also the dig. bars between car rockers and frame rails[under seat area]