What's needed to race?

[NovaMan]

For 11.50 and slower, you don't really need much SFI stuff. Here are a few things to start with:
Make sure your battery is securely held down. There are specs about 3/8" threaded rod and flat steel over it and stuff, but the most important thing is that it's secure. I've seen techs check this by grabbing the battery with both hands and trying to jerk it around.
Seal all the holes in the firewall between the engine compartment and the driver compartment.
Make sure your neutral safety switch works.
If you have an in-car mechanical oil pressure gauge, you have to have metal tubing, not nylon.
The wheel studs must thread into the hex portion of the lug nuts a distance equal to the diameter of the stud. Use open-end lug nuts so this can be checked.
You must have a one quart coolant overflow can.

Part of a blowproof bellhousing system is the block saver plate or motor plate, which goes between the block and the flywheel, but that's only necessary if you're 11.49 or quicker. Another thing that kinda goes with this rule is an SFI approved damper on the front of the motor.
You also don't need a roll bar unless you run 11.49 or quicker, but I think it's a good idea to put one in when you start getting air under the front tires. A 5-point bar will pass tech, but why not do a 6-point bar? IMO, an 8-point bar is really only applicable to unibody cars: the 7th and 8th points are the two bars that go down from the hoop and crossbar joint to the subframe connectors. My 2006 rulebook says it's OK for the roll bar to be bolted to the frame. If you're going to put a roll bar in your car, get a rule book and read it carefully.