SCCA roll bar rules for hardtops

I am trying to make sure my future challenge car will fit in a class, so can actually test it at an autocross ahead of time, but have been having a heck of a time understanding the safety rules.  Most likely, it'll be closest to A Mod or E Mod.  From some reading on various sites, I get the impression that at some point, if you had a hardtop vehicle in one of those classes, a roll bar was not required.  I don't see it called out as a specific exception in the current rulebook, but I also am getting the impression they are pretty much assuming the cars in those classes are going to be open top, as they seem to talk about them in particular, and just don't really mention hardtops.

Anyone able to enlighten me?

18.0.E. Safety Requirements
The following shall be required in all Modified Category vehicles:

4. The roll bar structure must meet the requirements of either Appen-
dix C or the Club Racing GCR required by class rules. Roll cages are
strongly recommended.

Sounds like I need to see if I can sneak it into a different class, or just accept that I'll miss out on some testing.

Cam you just Run-what-you-bring in a time only class?

AClockworkGarage said:

Cam you just Run-what-you-bring in a time only class?

I think it would fall under the ruling of a Special, but that also requires a roll bar.  It is possible a local region would have another class it could fit in, but I doubt it.

AClockworkGarage said:

Cam you just Run-what-you-bring in a time only class?

I've never quite understood how these classes exist. I guess there's a loophole in the rules because regions are allowed to do whatever they want with classing, but I would think it would be a bad time (for everyone) if there was an incident involving a vehicle that doesn't meet any officially stated safety rules.

We used to run an STO class. Seat Time Only. 

You got runs and times but didn't have to fit in a particular class. 

Yep we have TO (time only) in Atlanta too. No class needed, just pass tech for some basic stuff.

It has been pointed out to me by someone that the rules basically say the roll bar needs to meet the Appendix C requirements, but it doesn't actually explicitly say you need it.  Not entirely sure I agree with that interpretation myself and it may be a bit of rules lawyering, but I suspect I can take it up with the local safety steward before signing up for an event, and risking failing tech.

It might also depend on tires. With slicks, they may tech you like a Mod car, which I think needs roll bar if I recall. With 200tw, you will be treated as a XS/CAM car, which doesn't need roll bar.

3.3.2 Roll Bars
Roll bars or roll cages are strongly recommended in all cars. A roll bar
meeting the requirements of Appendix C or a roll cage meeting the requirements
of the Club Racing General Competition Rules (GCR Section
9.4, Roll Cages For GT And Production Based Cars, and/or GCR Section
9.4.5, Roll Cages For Formula Cars and Sports Racing Cars) is required in
all A Modified (AM), B Modified (BM), C Modified (CM), and F Modified
(FM) vehicles and all open cars in Prepared Category, D Modified (DM)
class, and E Modified (EM) class.

In addition to the time only class option, what makes your car ineligible for a X-Prepared or whatnot? If it's relatively inconsequential performance wise, or perhaps even just if you're also on 200TW or maybe even DOT-R tires, they also might be more willing to let you run as not-a-mod-class car but ineligible for trophies or something. The only way to know for sure though is to ask them.

Tim's basically building a custom frame, so that's Mod (slicks allowed, but mandatory roll bar) or XS/CAM (200TW, but roll bar not needed). I would just show up on 200TW and XS or TO markings. Maybe email the local organizer first about it.

Driven5 said:

3.3.2 Roll Bars
Roll bars or roll cages are strongly recommended in all cars. A roll bar
meeting the requirements of Appendix C or a roll cage meeting the requirements
of the Club Racing General Competition Rules (GCR Section
9.4, Roll Cages For GT And Production Based Cars, and/or GCR Section
9.4.5, Roll Cages For Formula Cars and Sports Racing Cars) is required in
all A Modified (AM), B Modified (BM), C Modified (CM), and F Modified
(FM) vehicles and all open cars in Prepared Category, D Modified (DM)
class, and E Modified (EM) class.

 

In addition to the time only class option, what makes your car ineligible for a X-Prepared or whatnot? If it's relatively inconsequential performance wise, or perhaps even just if you're also on 200TW or maybe even DOT-R tires, they also might be more willing to let you run as not-a-mod-class car but ineligible for trophies or something. The only way to know for sure though is to ask them.

The part I bolded makes it sound like a roll bar might not be required in DM and EM with a hardtop.

To expand on what machinenbau said, I'm shortening and z-ing a factory frame, changing the rear suspension design, and shifting the body backwards a bit.  Trying to build up the limits of challenge rules, and generally not worried about SCCA classing, just want to be able to run to get some practice and dialing in the car.

If I can't run in SCCA autocross, I'll do what I can on the street, legally, to get it roughly set up.

In reply to eastsideTim :

Correct. I read that as specifically not requiring a rollbar for hardtop cars in Prepared and DM/EM, and as such superseding 18.0.E.4's noting what requirements all roll bars for the class must be built to.

If your local club won't let you run under XP/CAM/XS/TO, see if your local club at least agrees on this interpretation. And even if not, it might be something to get clarification from the SCCA head office on if your local club makes you run it as a Mod class car though.

I doubt a custom chassis will be cam legal

"Must be an automobile or truck (e.g., pickup, SUV) manufactured for road use and legal to drive on US
roads. Non-US models are allowed, and right-hand-drive steering is permitted. Vehicles must have a
factory affixed OE manufacturer VIN plate. All vehicles must meet the requirements of Section 3.1."

"Exterior body panels may be modified or replaced in the original locations. The shape of the body must remain
recognizable as that of the original vehicle make and model."

Unless its a kit car replica I think you're going to have a hard time convincing people that a custom chassis fits. If you really wanted to, it looks like you could tube frame an existing car as long as it retains the basic shape. The intent seem clear that its street legal production car based.

Generally speaking, custom chassis are allowed and have been done before. They just have to retain the stock wheelbase and enough of the stock body to have a vin tag, which sounds like might not be the case in this instance.

dps214 said:

Generally speaking, custom chassis are allowed and have been done before. They just have to retain the stock wheelbase and enough of the stock body to have a vin tag, which sounds like might not be the case in this instance.

Wheelbase is different, but I will have the VIN tag.

eastsideTim said:

dps214 said:

Generally speaking, custom chassis are allowed and have been done before. They just have to retain the stock wheelbase and enough of the stock body to have a vin tag, which sounds like might not be the case in this instance.

Wheelbase is different, but I will have the VIN tag.

"Frame and Unibody may be modified or replaced to support allowed modifications. Subframes may be
modified or replaced. Vehicle wheelbase may not be changed except for small changes resulting from the
allowed replacement of suspension components or modification of suspension designs"

I'd guess that'll get you an inch or two before people start eyeballing it. Probably more designed to prevent from someone trying to make a 3/4 scale replica.

Yeah, unfortunately this will be quite obviously shorter.  Wheelbase will be over 9" shorter than stock, and I'll be cutting down the bed length to compensate for that and the body relocation.