Roll cage time

Well, I'd look at rules for potential places/classes you might run it. I don't know too much about road race rules, but I think in a drag application you have to use 1 5/8" main hoop, but your .188 wall is pretty heavy. Drag rules spec a .134" seam welded and I think .120" DOM. For 'moly you can get down to .083" but it has to be TIG welded.

First, talk intensively to a local, trustworthy cage builder who builds for the events you want. A dragrace builder may not be up on road race cage rules, and vice versa. I can only speak a bit about NASA (later maybe SCCA) since thats what I run. NHRA is prolly different.

But offhand, Larry is right, your material is too heavy. SCCA specifies either .095 or .120 wall depending on the type of steel (mild or CM), with DOM now being the only acceptable version (no ERW) for most cars of the Mustang's weight. .188 is going to be way overkill...a good cage is already adding 150-250 lbs to the car as it is.

The SCCA and NASA rules are also quite specific on tube direction, # of mounting points, door bar reqs, etc. Get the SCCA/NASA regs off the Net and read up, its all in there.

Now, if you are never going to compete with the car, then you can get by with ERW in NASA (HPDE). If you ever think you will race the car or get a logbook for it, do the DOM now or you'll have to rip it out later.

Additionally, make sure you pad any surfaces that might be hit by your head in an impact.....plus, if you run a harness crossbar at shoulder level b/w the main hoop, forget about backseat passengers unless its removeable.

Lman's right, talk to folks who race in the series/class you would like to run and ask them who does most of the cages for their class. Most road racing, and I'm sure drag racing, classes have specs on placement, mounting points, etc... Better to only do it once. Even if you never race you'll get a better cage.

*shrug* OK.....point?

I just got some pics of my (in progress) cage in my '68...I'll post when I get them uploaded.

Don't get .188 unless you like carrying around all that extra ballast. Rigidity is in the structure, not only wall thickness. A .095 cage done right is far better than a .188 cage done wrong. The standards are .095 and .120 for a reason.

You'll need more than a main hoop for racing, but then since you are into the rules, you know that. For OT I'd use a 4-point at a minimum.

I still think I'd cross reference the NASA specs with the NHRA specs and go from there. You may never want to drag race, but if you sell the car, it's more attractive to the buyer if it will pass. The Fairlane I'm building will likely never need a full cage, much less 'moly tubing, but I'm putting in both in case I decide to sell it. The car will be legal to 8.50 in the 1/4 though it'll probably run low 11's/high 10's at first. I also plan on running an engine diaper as well as a fire suppression system for both the engine and driver's compartments.

Good point about the fire-system. Ill be adding one with a nozel in the engine bay and cabin.