SteveG

Speedtoys, thanks for the extra information, a lot clearer now what happened.
To my uneducated eye, it looks like some credit goes to the lead car that he didn't start his turn yet, or perhaps he never saw the Camaro? Anyway, there is no comparison betw that cage and the one Sab is showing.

Speedtoys

Steve:

Thanks...that lead car..doing the right thing..saw him coming in his mirror..and left him that room.

Wasnt sure what was up, but he knew it wasnt gonna end well if he technically owned the line as he could have..so he gave it up to what was clearly a madman.

mark kibort

Hey, i like you too, but read below to back up what ive said.

Yes, im a big picture guy. I dont wonder why fabricators spend so much time welding cages, because I KNOW why! most cars are POS's. they need to put all the bars in because the cars are small and unsafe chassis, with very little strength. (saftey and for structure stiffness) a roll bar is to strengthen the B pllar, which as you know, is incredibly stiff on the 928 stock it basically has a roll bar, integrated in its chassis. have you ever cut one out? I have. its amazingly stiff. so as far as a roll bar goes, i would fee perfectly safe, with DE duty, in a stock S4 with no cage.

So by the way, do you think that fire, or crash physics know the difference between racing or DEing or Time trialing?? stock cars with driver wearing tee shirts seems to be acceptable with most organizations too!
i had some of my most fun, car to car , fender to fender, "racing" in DE many moons ago. in fact, also saw some of the most spectacular wrecks too. Cars that need cages are miatas, etc. Ive seen so many 911s that get twisted like horseshoes when they bang off the walls. Yet, ive been run into a wall at near 100mph, and the chassis did its job with a mininmal cage. plus there is something to be said to keep the chassis' ability to have crumple zones to absorb energy , as long as you dont get passenger compartment penetration. in other words, some cages are way too much and are MORE dangerous. guys are timing trialling all over the country with 500-1000hp monsters without cages, running SpeedGT WC times at a track near you. Do DE guys wear fire suits?? even gloves?

You have to use your head about this. a roll cage is nice to have in a 928. it provides stiffness as well as increases some side impact protection at the far rear of the seat. roll over isnt helped much as the stock B pillars are very safe. however, if you had a car centerpunch you while on your side, that would be a good case for a roll bar. (very rare by the way). whats more likely are side impacts , and the stock 928 door bar is flimsy, so why not stress a full cage then for all track use?

the roll bar can be bolted to the floor as it is designed to to. its adaquate for the duty that the car will be seeing. light racing or time trialing as well. thats why PCA, NASA and others allow for roll bars for TT and some light/lower performance car racing sanctioned by other organizations.. The 928 floor, as thin as it is , is stronger than the floor of toyotas for example.

As a racer, the only structure i really look at life saving as a bolt-on is the full cage side bars. the rest, as you have seen via the 928 getting crushed video for a movie scene, its so strong, even a monster truck cant crush it without it being pre-cut. now, take a look at other cars at the track, especially other tubs. there is nothing that compares to the 928 chassis. THATS why a perfectly safe cage can be as little as a 6 point, with only reienforced mounting plates to the chassis mounts.

In summary, a roll bar, is for protection of a roll bar.very few cars have the protection that the 928 has without any modifications. in fact, i would be worried about any crash that could tax that structure, If the driver, who is more than likely, using stock seat belts and no HANS.

mark kibort

I had a complete brake loss too at Laguna, but not as a dramatic outcome. we are talking complete loss of brakes. This is where keepng your head can save your life or car. a quick down shift and some yanking on the wheel might have saved him, as sticky tires have amazing braking capability turning full lock!
I had a lot more runn out at laguna, but the speeds were greater too. He didnt have a lot of time, but instictively when i watch this, im thinking "grab 3rd" at the same time brakes are applied. (or not applied but not working). that would have saved his Arce. i feel for the guy. thats a nasty wreck.


yes, he lost brakes, but didnt turn the car as much as he could have if he downshifted , which would get the car slowed to a very managable speed. he might not have made the turn, but he would have misssed the tires .

any 928 would have survived that crash without any roll cage or reienforcing bars.

as another side note, when you do a cage, copy what i have done with mine . its functional and safe. you only need .175 x .095. the AP stuff is roll bar thicknesses, and that is the .120 thickness. better to start from scratch if you do a weld in cage. you can make it really nice, and near streetable too.

Speedtoys

I had a complete brake loss too at Laguna, but not as a dramatic outcome. we are talking complete loss of brakes. This is where keepng your head can save your life or car. a quick down shift and some yanking on the wheel might have saved him, as sticky tires have amazing braking capability turning full lock!
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That's what he did.


I had a lot more runn out at laguna, but the speeds were greater too. He didnt have a lot of time, but instictively when i watch this, im thinking "grab 3rd" at the same time brakes are applied. (or not applied but not working). that would have saved his Arce. i feel for the guy. thats a nasty wreck.
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You dont get to re-write physics..from the braking zone to the grass is not enough time to slow down much of 120mph sideways..having grabbed a lower gear, and pitching to scrub speed.

Where do you make this **** up Mark? YOU would have shifted the laws of physics somehow in your favor? I wasnt gonna say anything..sat on this for 2 days. And im calling it out. Im not normally like that, but you're not doing racing a favor here.


yes, he lost brakes, but didnt turn the car as much as he could have if he downshifted , which would get the car slowed to a very managable speed. he might not have made the turn, but he would have misssed the tires .
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Every accident is easier to avoid after repeated review of the video. After it happened. What happened, happened. Its not exactly a procedure to master and train for..give the guy a break.

any 928 would have survived that crash without any roll cage or reienforcing bars.
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You are so full of it your ears are leaking brown Mark. PUT DOWN THE 928 FANBOI SCHTICK. (You make Apple fanbois blush)

Sorry..when a car shatters concrete barriers BEHIND a thick pack of tyres, its not a vehicle survivable moment. And being thrown airborne...too. Good Christ Mark..


As another side note, when you do a cage, copy what i have done with mine . its functional and safe. you only need .175 x .095. the AP stuff is roll bar thicknesses, and that is the .120 thickness. better to start from scratch if you do a weld in cage. you can make it really nice, and near streetable too.
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Agreed. Patching another cage to a specific fit, is junk...and devalues the car to the next racer you want to sell it to.


PS: Whats your car weigh? Lets do the math on the likely impact forces here..lets see what alien metal your car is made of that could absorb it.

You >3000lbs with cage (round numbers work better)

IcemanG17

SAFETY is not an area to skimp on.......sure it costs money and weight.....but it is worth every penny and pound.....

Yes I race a "crap can" 928....but safety I DO NOT skimp on.....my car has a true 1.75-.120 DOM cage....not just the main bars, but EVERY BAR in the car.....my car was built just prior to the video incident, but we included an ankle bar for the driver, just in case something like this happens....I also run a Racetech halo seat ($1300) and schroth harnesses....why...because they are the BEST...and I will NOT risk my safety or that of my drivers to anything but the best....

the 928 is a very well built car....but it was designed 40 years ago......a properly designed cage is required for a race 928.....I have no doubts about mine....I can jack up 1 rear wheel only a few inches and the same front will come up too....the chassis IS that stiff.....BUT when I upgrade my engine to the power level of the car in the video I will upgrade the cage.....better ankle protection and support braces under the hood at a minimum....

mark kibort

wow, i dont think we are debating on safety, as much as you think.
But , i think you are underestimating the saftey of the 928 chassis as compared with the camaros and mustangs i race and see at the track. My car weighs 3000lbs.
the crash of the camaro was at an angle to the wall, and as dramatic as a car going air born is, its MUCH less impact on the chassis, as all that energy is used in tossing in the car in the air, lengthening decelleration time. when i punched the wall at near the same speeds as this car when i got run off the road by the out of control honda. i stuffed it into one row of tires and cement. Yes, it crunched the wall too! you saw my chassis. it did what it was supposed to do, and in fact, the cage had nothing to do with it. most wrecks are like this, although when i see the more tubed frame cars wreck, i see all sorts of dangerous footwell collapsing a transam wreck showed this in spades the last race at thunderhill last season. sometimes a production chassis is much safter due to the mass and structure of the unibody .

never said that the 928 would have survived this crash,but the passenger would have in a stock 928 for sure. the cage is really for side impact, impacts to the roof, (landing on barriers upside down, or cars hitting you whle inverted) the stock 928 can handle a massive roll over , without question. again, if you have ever cut through one, its quite diffeent than our american counterpart chassis. If you want to see my video of the plasma cut through the B pillar, let me know!

as far as the wreck, this is a common problem with most brake line caused accidents thats why i try and also teach , the brake zone down shift at the same time. that way, if the brakes are gone, you are already grabbing the down shift gear. this slow and lazy shifting that most racers do, is not safe in most conditions. certainly would have saved him. im going 130 down the straight at laguna. you can see the distance i traveled. its not much more than t-hill , but enough to make it an off track event, but it wouldnt have been a tire/wall crusher event. thats a side bar. evasive actions in racing.
I do feel for the guy. he did everything he could, but the downshift and that , as simple as it sounds would have saved his ****!

so, back to topic, if you are fitting a roll bar for DE , time trail , etc in a 928 I wouldnt give it too much thought. just bolt it in and be cautious for the surface you are bolting through. any other car, its more of a life saver, because most other car chassis are very flimsy compared to the 928 chassis. this you should know . its not boastful bragging. its the truth. 928 chassis is a beast!

Rob Edwards

C'mon Mark, really? I do love your racing exploits but I have to say that you're full of it with your approach to safety. I hope it doesn't ever bite you in the ***.

mark kibort

I just seen a lot of it, and know what is reality and what is just "feel good safety".

lets face it, folks DE all the time get in crashes all the time, and with little racing protection. why dont all DE cars in any sanctioning body require more than an old helmet and lap belts?

Back to what i was saying, the roll bar is just an added layer to most cars saftey. the 928 has a massive structural area called the B piller. no car compares. unless i was doing laps at the "Ring" , i would have no problem DEing or time trialing a un "hooped " 928. not too many cars i would say that about. again, we are not talking about tossing out all safety equip. the original poster was wondering how to mount his roll bar. (not build a full blown race car) . I would not race at the speeds I run at in my car, door to door without a full cage. MOSLY because of the side bars and A pillar protection. go look at a Vet before the cage is put in , and look at the chassis. there is nothing really there! the 928 is an amazingly safe car from the roll over, and head on crash protection perspective.

If you do some research on most racing accidents, the deaths are usually from high g forces to the head and neck. thats is where the protection should be. rarely , in our type of racing does the body contact the driver.this is generally due to the side bars. (not part of this discussion) and rarely does the hoop do much in a roll over, unless someone runs into while you are upside down. (also rare)
the point is, the roll bar is for street cars to be a little safer on the track, but does not turn them into race cars as far as safety. its a bolt on device, serves a little purpose, unique to the 928, it will do little in a roll over compred to the 928's stock structure of the B pillar, so i wouldnt worry about reinforcing the floor mounts, the steel down there is find for the applicatoin, but stay away from the weaker , circle cut out area and you are fine.