what all can be done to stiffen the body up?
plan on making a front and rear strut tower brace.
what else is there though?

 

Are you talking about an f-body or your rx-7?

 

rx7

but I am willing to take any ideas even if they are something that works on a f-bod and your not sure if it will work on the rx7
just need some ideas though

 

subframe connectors would be a big improvement, thats if your car can use them. Is the rx7 a unibody?

 

roll bar would help too if your planning on going that fast

 

yes it is a unibody

I am thinking though that it might have sfc stock
looking under the car there are two rail like pieces going from the front of the car to the rear. not sure though

 

I was just under a 86 rx7 removing a trans. thats the subframe you are talking about , unless someone already installed subframe connectors

 

how about running continuous welds where all the spot welds are? or just adding spotwelds? strut tower brace of course. tieing a roll cage into SFC's. Maybe a rear strut tower brace/shock tower brace.

 

I don't really see how tieing a cage into sub frame connectors can really help out all that much on a unibody car. I mean if it's installed correctly there will be 6 inch sq plates under each tub MIG'd or TIG'd to the floor. I know on full frame cars it's mandatory in the NHRA handbook (one of last year I printed on the net).

From my print out it says.... "cars with unaltered firewall, floor and body (from firewall rearward, wheeltubs permitted) running between 10.00 and 10.99, roll bar permitted in place of roll cage, or per class requirements."...

"On all cars requiring a roll cage, if the OEM firewall has been modified(in excess of 1 sq foot for transmission removal, not including bolt in components) a lower windshield or dash bar is mandatory."

So from what I get as long as you don't break 135 mph or 10.0 you can run a roll bar with an unaltered floor board. If the floor board is altered more than 1 sq foot (possible when you consider cutting for main hoop and sidebars since there 6 sq inch plates) you have to also run a cage and a dash bar.

I just don't really see why everyone goes off on cutting the floor to weld plates directly on the sfcs. Anyone got any ideas? I'm just a newbie when it comes to this roll bar and cage stuff so feel free to correct me.



I also read on another post that rear strut tower braces don't do all that much for our cars unless it's an independent rear, which the rx7 might be... I haven't ever seen one up close.

 

well if you had 2 rails ( SFC's) welded to the front and rear subframes and along there length to the rockerpanels, wouldn't it make more sense to join them with a hoop or a crossbraced hoop directly instead of the sheetmetal above and around them? I would think so. The NHRA rules are mostly for safety ( i believe) and rollover protection. If you were looking for increased chassis rigidity or torsional stiffness i think i would be better to go to the SFC's and the floorboards than just the sheetmetal floor. IMHO.