When I bought my 1988 Civic ex-Honda-Michelin car, it came with this roll cage (bars in red). I am still using it today, but transferring it into a newer chassis (1991). At the same time, I'd like to make it legal for more series and, AFAIK, by adding the yellow bars, this cage will become NASA legal. The two bars that extend to the back of the car have bends in them, which is illiegal (they were designed to clear the rear seats). The material is .120 1.5 inch DOM steel. My question is this: should I remove the two bars that extend to the rear when I add the yellow bars from the main hoop to the rear shock towers? I don't see what purpose they serve except to prevent the rear of the car from crushig in on impact. Is that useful, or dangerous, or what? If I keep these bars on top of the yellow ones, should I have the yellow bars join the main hoop at the same point as these bars, or at a different point (further in the middle, further down the sides, stc.). Thanks all.

 

I don't know if it matters in the NASA rules right off hand but those tubes would constitute two additional pick-up points - and illegal ones - in SCCA IT. This could be a PITA if you want to drop in on an ITE race somewhere.

K

 

i never really thought about IT, but it's a good point, if my car is eligible for ITE.

 

If you are swtiching tubs, I would just get a nice cage built by a local builder in the new tub.

 

Keeping the car within the standard 6+2 point configuration would be a good idea in terms of it's value (with the +2 referring only to the allowed firewall braces). If you're going to have a cage that limits your legality, you might as well do it right and brace it all over to the body and through the firewall. You really have two options to "straighten" your rear points: you can change to the yellow bars in your diagram going to the rear suspension points, or you can replace the rear red bars with straight bars going to the same mounting points that you are currently using (this is the setup in my CRX, for example). If you have welded plates or your rear supports connect to the sub frame, this might not be a bad idea vs. new plates on the rear fenders.