This shows the driver’s side factory sub frame after I cut it open. Take your time and make it snug.
|This is the passenger side front strut bar I made and you can see it went right through a factory hole! I also ran a support tube from the bend down to the outrigger.|
My original intention was to build a roll cage that would meet NHRA’s standard requirements to run between an 8.50- and 9.99-second e.t. As previously mentioned, I had already added a few extra bars to more effectively triangulate the kit from Comp Engineering; not that it wasn’t a complete kit and perfectly safe and legal, but I just can’t ever leave well enough alone it seems!
Then, to my dismay, NHRA announced that ALL the Super Stock Modified class cars would be required to have an SFI spec 25.5 certified roll cage in 2009. Actually, I guess the timing was pretty good compared to having the car done and then finding out! Geez, my laziness actually paid off for once!
It appears that some of the killer cars in the class are almost running in the 7’s so apparently NHRA decided to get a jump on things. Even though I am planning on running with one carb to begin with in Modified Stock I would entertain the thought of slapping on another carb in the future with a tunnel ram setup and run in straight Modified, so now is the time. So, I ordered the specs from the SFI Foundation for $35.00 and ordered more tubing. I gotta say, the two people I spoke with and asked questions of at the SFI Foundation were very pleasant to deal with and gladly answered all of my questions.
There are a few different chassis spec designations available depending on how much of the stock floor is to be retained and the material used but mine fit the 25.5 spec which is a mild steel or moly material, stock floor with rockers and firewall. It also allows for 2x3 frame rails and connectors. Whew! After the initial shock of the 20-plus page manual wore off I realized that basically all I had to do was add a “Funny Car” cage to the existing main hoop, add rocker sill bars, “X” braces in the door openings, a dash bar, roof diagonal, gussets at the roof weld joints, and what is referred to as a seat bar. Is that all? Shoot, with my pace that shouldn’t have added more than a month of work!
Had I known this was going to happen I probably would have built the entire cage from chrome moly to save weight. But, I had 70% of it done already so I guess it is what it is. I still think I will end up around 3200 lbs. with driver, so I should be okay. I had the main hoop, windshield bars, and halo bar installed already and was pleased with the fit. They were from Comp Engineering.
I decided the first 25.5 component to add was the Funny Car cage. I busted my old hydraulic tube bender out of the mothballs and went to work. Most of the 25.5 bars are made from 1 ½” .120” wall mild steel. Some of the braces are made from 1 ¼” mild steel. I can’t really describe how I decided upon the Funny Car cage main hoop design because I basically made it how I thought it should look. Of course there are some basic 25.5 specs on where it needs to be attached but they give the builder a fair amount of room for creativity. To my amazement, as rusty as I was at using the old bender, I was able to carefully make the hoop out of one continuous piece without ruining it on the first try! The pictures do a good job of illustrating how everything turned out so I won’t waste anymore ink on that.