mjensen

I would like to know as I am having a cage built, if anyone is doing both, driver and passenger nascar doors or just the driver door on my 951. I am building my car as an F class PCA and a GTS NASA.

Eric in Chicago

I have bars in both doors. If anything, it will add more stiffness, one side could lead to a slight twist under extreme conditions. That is just a guess on my part. Going racing this season? Maybe I'll see you on the track!!!! (red 944s2 with big yellow hornet on doors and hood,#400 with NASA and PCA)

keith

save the weight - do Xs in both doors, with a sill bar. On the driver's side, kink it into the door and gusset, if you like, like 996 GT3 Cup door bars.

mjensen

Thanks, I like the kirk racing cage options, I have a certified welder to finish the job. I thought I would go with both nascar doors if the rules allowed. I will be racing with NASA and PCA this year, going for my "rookie" license @ BFR in april with NASA. I will be running a black '86 951(don't know what number yet...).

Cory M

The Nascar door bars are heavier and I don't believe they will be as stiff as an X. If you want more room on the driverside you can put a slight bend in the bars that form the X.

Here's what I did:

keith

I prefer them kinked right at the intersection, for strength. I've seen the wavy, double-S bars fail. (they like to fold with a lot of unsupported bends)
my preference
other view

Geo

An X that is not in a single plane is weaker than the flat X. You have the same issue as with NASCAR bars in that the bars are not the shortest distance between two points. They also don't have the torsional rigidity.

Rather than being the best of both worlds, and non-flat plane X is probably the worst of both worlds.

keith

I'd personally take a gusseted, kinked X to save my elbow (gusseted for strength) over a close-to-my-arm X on the driver's side. The Kinked X will transmit a lateral impact into the surrounding framework of the cage just fine - it is the frontal offset or rear offset impact that betrays its weakness, which is why I always want to see a sill bar to transmit some of those forces.

I've recently witnessed a wavy-X, no-sill bar car fold the floorpan (and as a reault, waste the tub) as a result of poor design.

While I agree with Geo on the face of it, I am attached to my left arm (pun intended). ;^)

How've you been, George?

Cory M

No doubt that this is true, but every cage is a series of compromises to make the cage fit the car and driver. In my particular case the slight (7 degree) bend in the drivers side door bars was critical to properly fit the driver in the car comfortably. The other options I had to get the room I needed are just running a single bar or full Nascar door bars. I wanted a little more protection than a single bar and I felt that the Nascar bars were overkill and too heavy (with a 220 lb driver I have enough weight bias on the left side). Bending the bars at the vertex is good practice but because I can't gut my door without going the Nascar route it wouldn't have given me the room I needed where I needed it. Keith makes a good point about the offset impacts, I'll have to think about adding sillbar to regain some of the stiffness and a support tube to increase the strength. Although, if the front or rear impact is hard enough to crumple the tub it may be a good thing that the energy is dissipated that way rather than transmitted to the driver...

keith

... which is why I don't run cage tubing any further than suspension pickup points - let the fore and aft crumple, protect the middle (and stiffen the suspension box!)

Geo

Those words are true. And I freely admit to making a couple of compromises in my cage for similar reasons.

Geo

I've been good, but the last 5 months have been crazy. I haven't touched the car in the last 2 months which is a shame because I only need a weekend (probably just a day) to get the car ready for paint prep. The few weekends I've had I've needed to just have some downtime - especially in the last two months.

To stay somewhat on topic, how did you go about painting the inside of your car? The cage certainly complicates matters (like getting to everything w/o getting ON fresh paint) and since our cages are pretty similar I thought perhaps you could give me a few tips. I sure do hope to be painting before TOO long.