Hello all,
This is my first time posting on the forum, so apologies if the format is off. Anyways, I was wondering about a rule clarification for the roll hoop for the $2000 challenge. I don't have access to a tube bender, so I was going to make mitered cuts and weld the roll hoop together and then add gusset plates. I've been looking at NHRA guidelines and don't see anything about the roll hoop having to be one continuous tube, so I just wanted to check here before welding it in. So are no-bend(specifically mitered) roll hoops allowed in the $2000 challenge?
Thanks in advance!
I know SCCA specifically requires a single bent tube for main hoop. I agree NHRA rulebook does not explicitly call it out, so it may be up to the local tech inspector. Hopefully Tom can weigh in.
There are lots of places you can order a pre-bent sections of tube to your specs. Try asking a local race shop, I'm sure they do a couple of bends cheap.
Summit sells pre-bent main hoops for just under $80. Will your car be fast enough to require a bar according to NHRA rules?
They are sold on Bezo's site too:
Where are you located? There are a few people here with benders. If you are in Florida, I'll bend something up for a Challenge car for a case of Diet Mt. Dew.
The rollbar I built for my E28 is based around one of those Competition Engineering main rollbar hoops (C3122 for anyone that stumbles onto this thread) that I bought through amazon up here. They list the dimensions so you can figure out if one will work for your application. In my case the fit is very good with about a 1/4" clearance to the back door cards and tight to the headliner, hopefully there is an option that works as nice for you.
I just bought a length of DOM tubing to do the rest rather than buying one of their finishing kits.
In reply to jgrewe :
What part of Florida? And are you able to bend 2" od 1/8" thick tube?
Tube should be DOM and not seamed.
Also, if you are patient and have access to a torch and a vise you can do nice bends yourself using sand. I have done a few cages that way.
mikkowest said:
In reply to jgrewe :
What part of Florida? And are you able to bend 2" od 1/8" thick tube?
How heavy or how fast is this car? That's crazy big (heavy) tube.
Also, don't build a hoop with welded sections. I can't think of a single sanctioning body that allows it.
If it doesn't need a hoop, don't add one unless you are adding all of the other safety gear (imho).
In reply to mikkowest :
St Pete. I only have 1.5" and 1.75" dies. A 1.75"x.120 DOM cage will work in any weight car in SCCA, I don't know what NHRA requires.
In reply to Adrian_Thompson (Forum Supporter) :
We've asked a few shops already, but none have a large enough tube bending dye.
Basically, we were able to get a bunch of 2" od tube for a really good deal, so we have been using 2" for our chassis, but this also means that we haven't been able to find someone capable of bending it. Also, because we already built most of the chassis out of 2" and a lot of it connects back to the roll hoop, we don't really want to have to buy smaller od tube.
is it possible to order a pre-bent 2" tube?
In reply to wvumtnbkr :
Yeah, we're aware the tube is super heavy and not typically used, but we got an amazing deal on a bulk order of it, so we wanted to use it in spirit of the $2000 challenge(where we obviously have to be cheaper due to the restricted budget).
Our car won't be crazy fast as is, but the reason I'm including the roll hoop is so in the future when we add more power, we won't have to worry about it not passing tech. Also, we want our car to be safer as we're using an old car that isn't very stiff nor safe when it comes to rolling over.
Nhra roll bar needs to be a single tube main hoop out of 1-3/4" ms or 4130 (wall depends on which. A full cage reduces that to 1-5/8 but needs more bars and the roof hoop or roof/pillar bars need to be one piece.
The 2025 nhra regs are up and you can find details near the end in the general regulations section. Bar under 11.50, cage 9.99-8.50 and needs certified.
