Nathan Muir

FBB is spot on the knee bar is not for knees but to send energy across to the other side so it can help to keep the A pillar bar from bending in taking the nice X or nascar bar with it.

FBB, Go to Home Depot and look in the flooring section. Thy make anodized aluminium floor stripping that is intended to go under tile flooring and act as an transition edge for the floor. It is L shaped and the long leg is fully punched out in a triangular web pattern. I "field tested" some (read tried to bend the crap out of it) and it is very strong and light. The short leg is just long enough for pop rivets or other small dia fasteners to use through the lexan or you can glue the short leg to the plastic using lexan safe glue that looks like clear caulk.

The nascar bars in post #24 look like they were added to cover a ruling in a book. They do not look like they are pass through but are welded right to the sheet metal of the door jamb. Almost looks like a "we gotta do this to get into thih race" kind of work. some base plates would have helped and the work is not to par with the rest that can be seen.

Mark in Baltimore

fbb,

Thanks for the input. I'm deleting the stock knee bar and adding a cage knee bar. Sorry for the confusion. I was answering Nader's post who was answering my original query on removal of the stock knee bar to facilitate addition of the cage knee bar.

Bryan Watts

Sure it will...anything that is bent OUT from the plane between the A and B pillars can also bend IN. Whereas bars placed in the plane (whether X or not) would need to stretch along their length to move closer to the driver.

Bryan Watts

I really doubt that they are welded directly to that sheet metal as the only supporting point...that wouldn't suit any rules that I've ever read, whether club or Pro.

Cory M

The "bent out - will bend in" argument makes sense in theory, but in practice I feel that it is way too simple because it doesn't make any account for buckling. In an ideal test case the bars may be loaded so that all of the deflection is due to the stretching and bending of the material, but in the real world it doesn't happen like that. Once the material buckles or fractures all of that bending theory goes out the window.

kurt M

Ouch! that is what I worry about most a punch in the door.

In the first image the bars dont look like they go through to anything and one case point is the front two bars. They end in an area that would be very hard to continue through and then welded to something internaly. I can't see the rear bars termination points but the front and sill bar are all in hard to reinforce locations if you go inside the rocker or A pillar. The two in front are also right next to but not going to the A pillar bar. They could have easly been run right to the A pillar bar. I would like to see more on that setup as the original work looks to be very well made.

Bryan Watts

It's a BMW Motorsport cage from the factory. The additional bars were added by PTG to meet Rolex rules...the same chassis was previously run in ALMS without the additional door bars. I honestly don't know how the additional bars attached, but I would be comfortable assuming that they attach more structurally than what you see. I really just posted the picture to give an example of what a setup with X and some crush bar would look like.

Greg Fishman

I think this car (or its twin) got a nice test session last year at Mid Ohio when Joey Hand had that horrific crash. I think it would be safe to assume that PTG does things the right way, even if it is hard to see those things in a picture.

kurt M

I was thinking the same thing and wondering if this was the car that went through the wash cycle at MO. Not trying to take a good thread off topic just interested in the car and work.

Thanks for the image of the x bar that gotr punched. It folded as i would expect with the area near the tacos failing first. I am planning to taco the front and rear triangle of the drivers X in the car I ma building fully to the A and B pillar. Standard size on the top triangle so I can still get out in a hurry.

JPhillips-998

Mark,
I was the one that was working with Donna and the committee on permitting NASCAR bars on the passenger side. It was quite a process but ultimately approved. She was going to check my car out at Road Atlanta but the full cage was not complete. It will be done for Mid Ohio.

Donna told me when the notified me of the approval that she would be putting something in the next Club Race News to the effect that they are now approved.

fatbillybob

Thanks Nathan!

Mark in Baltimore

LOL. When she responded, she wrote, "Thanks to a persistent racer who raised the issue about a month ago..."

Thanks for taking the time and effort to pave the way on this one, Jeff!

Mark in Baltimore

I've decided to have Mitch Piper gut my doors and put in NASCAR-style bars with a slight downward angle in the top tube for better ingress and egress. From what I was told, more and more sanctioning bodies are going to require NASCAR bars. As it is now, I will retain the use of the stock glass, which will be held in place with a special tab but will slide up and down in the window tracks as it did when it was motorized.

Even though my tagged and titled 993 sees the street maybe two times a year, I was initially a bit reluctant to get rid of my electric window lifts. What if I wanted to go to MacDonald's and pick up a Big Mac? What if I had to go to Home Depot for some plywood? Additionally, when the windows are down and a thunderstorm hits the track, it sure is easy to turn the ignition key and then raise the windows. However, I decided to sacrifice convenience for safety.

I could have gone with the X bars and agonized over the inherent stiffness of the triangulated design over the NASCAR bars. But, hell, I had been running a roll bar with very little extra chassis stiffening for over three years now. Anything would be an improvement and, even then, would a 15% increase in stiffness really make a difference in my lap times?

As to the greater weight of the NASCAR bars, Mitch said that, based on the weight per foot of the tubing, I would only be looking at approximately 3-4 lbs more, weight that would be more than compensated by removing the door panels, sheet metal and window regulators.

I opted for NASCAR bars on the passenger side because I wanted chassis stiffness symmetry. I'm not sure how much stiffer the X bars are, but I didn't want to have some sort of weird imbalance by having two different designs on the left and right sides of the car.

Ultimately, I chose the NASCAR bars because I imagined sitting in the car with an X bar an inch or so away from my elbow. Then, I imagined a NASCAR bar six inches away from my arm. That extra space sealed the deal for me, along with the understanding that NASCAR bars look to be the way of the future.

As an aside, NASA may soon be requiring X bars in the roof. My initial plan was to have one diagonal built into the roof, but I decided to put in another bar and just be done with it. Hopefully.

Thanks to everyone who contributed to this thread!

Ed Newman

This winter I installed a new cage in my car so this is my $7000.00 (instead of $.02)...

1. I have and continue to be very outspoken against Donna and PCA. I believe a cage should be manadotry in almost all cars and double doors bars are an integral part of the package. PCA club racing is a crossover between DE and pro-racing and they need to remember that most club racers are also DE instructors or students in whose cars we (I) have to instruct. PCA rules require the passenger seat remain, we damn well better have proper protection for any passenger. Donna, Bruce, etc. Would you want to go for a ride in a car with unequal protection for you as a passenger?

2. Give me one good reason we should not allow removal of the passenger door panel. Weight is not a reason as the bars often weigh as much as the panel and the car still needs to make minimum weight

3. Based on my research, different cars benefit differently from X bars vs NASCAR bars. Cars with fiberglass doors which proide little impact protection should run NASCAR bars. Cars with steel doors and factory side impact protection (i.e. 993, 996, 997) should run X bars and leave the factory parts intact. The factory doors are designed to provide a crumple zone and the X bars allow that were NASCAR bars would block it and immediately transmit all force to the main cage and in turn the driver.

May 1st was the opening of the rule change submission period, I would ask everyone to write to Donna and make 2008 the year of "safety" in PCA. Demand that PCA update the rules to require HANS devices, require full cages, require door bars, require window nets on the cage and not the doors, etc. Lets stop ignoring the fact that what we do is dangerous and we need to take every step to protect ourselves and other.

How would you feel if God forbid you T boned someone racing and killed or seriously injured them because they did not have a proper cage with door bars. Time to fix the problem!

leif997

Good points, Ed. "sorry" instead of "safe" will not make broken bones heal faster...hope PCA gets on the wagon.