Auto Power Industries/DSE/Tiger Cage

[NorCal72]

Having a tough time deciding. In the end I don't think I could live with myself if I paid for a Tiger Cage (as nice as they are). I think the API setup looks like a damn good deal. Has anyone used them? It seems like a pretty good compromise between the DSE setup and the Tiger Cage. I was looking at the bolt in DOM cage.Its going in a gen II Camaro. Thanks in advance for the feedback

http://www.autopowerindustries.com/pricelist.asp

[Sieg]

I understand where you're coming from on the Tiger Cage, really like the product and options but it's not rated and exceeds my budget.

The Autopower looks to be a good affordable option that appears to be rated and they bolt in. The race roll bar with bolt in cross and harness bars looks to be the ticket if you're doing any track days.

You just need to have it striped, prepped, and powdercoated.

Hopefully some will chime in with fitment and build quality information.

[Bryce]

before you go with API read this http://forums.evolutionm.net/motor-sports/604547-un-official-autopower-roll-bar-thread.html

[Sieg]

before you go with API read this http://forums.evolutionm.net/motor-sports/604547-un-official-autopower-roll-bar-thread.html
Thanks Bryce.
I wanted to confirm mount points with AP because I was curious as to how strong those points would be and if installing reasonable reinforcing would be possible. The shorter sunroof version looks like the way to go.....if the mount points can be reinforced.

I'm really glad Lat-g doesn't have in thread advertising like that.......it drives me crazy!

[badmatt]

I'm still personally unsure about the whole "bolt-in" cage thing. But that's just me.

Id rather have a cage tied into the structure of a vehicle (sub frame connectors with and out rigger going to the rocker) Or the frame.

Not bashing anybody's product line. Just my personal opinion.

Matt

[XLexusTech]

THe thing about the tiger cage that makes me wonder is, its been several years since it came out and still no Cert?

[Sieg]

I'm still personally unsure about the whole "bolt-in" cage thing. But that's just me.

Id rather have a cage tied into the structure of a vehicle (sub frame connectors with and out rigger going to the rocker) Or the frame.

Not bashing anybody's product line. Just my personal opinion.

Matt

But better than none for a primarily street occasional track day car? Provided it can be reinforce enough to keep it from punching through? Thus making shoulder harnesses an option that add an element of vehicle control. :headscratch:

[Bryce]

THe thing about the tiger cage that makes me wonder is, its been several years since it came out and still no Cert?

I believe it has a cert in the east coast timing association???????

Also remeber that a NHRA roll bar or cage is differenet from an SCCA roll bar or cage. They have different requirements sometimes they contradict eachother. SCCA does not require a cage for pro-touring cars, but if you have one it has to be per their rules. At least thats the way I read their rules.

[NorCal72]

before you go with API read this http://forums.evolutionm.net/motor-sports/604547-un-official-autopower-roll-bar-thread.html

Jesus, that's a eye opener. I planned on making modification's to reinforce the cage and tie it into the sub frame connectors. I have the resources to build/modify a cage I just wanted to get off to the best start possible.

[Ron Sutton]

Roll Bar Safety

Since I have a long background in chassis building & a lot of real world crash experience where people lived & died ... I figured I'd chime in with some advice & guidance. To make this official, I need a soapbox to stand on. :soapbox:

In my driver development program, we lived, breathed, taught, practiced & required safety. If one of those young drivers had been disabled or died on my watch, I don’t think I could live with myself. I required HANS devices & have full containment seats before the racing sanctioning bodies did.

We required a 3-layer nomex suit with a fire rating of TPP # of 21 or greater. There are a LOT of BRANDS with suits that test below 21. In addition, we required nomex or Carbon-X underwear long johns, long sleeve under shirts & socks. (Carbon-X is best)

My young drivers personally commited they would protect themselves, as a promise to me. One driver showed up at the track without his fire retardant underwear. No Nomex/Carbon-X … no driving my race cars. “Aw Ron, but it’s just practice. I’ll have it on tomorrow for the race.” Not no … but hell no. He ran & bought some Carbon-X underwear & made the last half of practice.

I have lost friends because they were “just”. They were just practicing, just playing around, just testing. Cars, guard rails, cliffs & concrete barriers don’t know you’re just playing, just practicing, just testing, etc. A drag racing friend died in 1985 doing a private test. He had his helmet & 5-point harness on … but not fully tight … because they were just testing. But when a car flips & crashes … the forces don’t know you were you “Just …”

I had a young driver, hit the concrete wall on a practice day at a ½ mile track when I wasn't there. He was hurt & bruised bad, but otherwise ok. Some of the injuries suggested he wasn’t wearing his HANS. He wasn’t … and I dropped him from my program. He broke his promise to me to be smart & protect himself in this dangerous sport.

I’ve been on fire, been upside down at 177 mph, hit walls so hard I’m lucky to be alive & broke my back in 1991 … almost didn’t walk again. This stuff is serious. If you’re going to build your car to be more like a race car … and drive it in race situations … then plan for race level safety measures. The sport of Pro Touring … where drivers compete in AutoX, real road courses & fast events like the Silver State Challenge … are just asking for someone to get killed or disabled … because there are less rules.

Don’t let the lack of rules guide your safety.

-----------------------------------------------------------------------------------------------------------

In my drag race chassis building business, we had a funny … but true … phrase we’d use. We built our cars to win races … and protect the driver. We called our additional safety procedures “our client retention program” … and with a bit of tongue-in-cheek-humor, we would tell prospective clients, “if you crash one of our race cars & live … you may buy another one. But if you crash & die … you won’t be buying any cars.”

We built our cars with methods that took more time & money, but protected the driver. We didn’t allow the customer to choose parts if they affected safety. All of this safety was “built into the cost” and wasn’t “optional” to the customer. If they didn’t want to spend the money for our level of car & safety, they weren’t our kind of customer.

Don’t want anyone dying on my watch … and I have seen too many people die … including a prospective customer who went somewhere else because we wouldn’t use his homemade fuel cell. Another chassis builder did build a car with it.

The fire didn’t kill him … when he went through the guard rail at Green Valley Raceway in Ft Worth, Texas. The fuel cell ruptured & broke free, allowing fuel to go forward in the cockpit. He died 4 days later in the hospital from pneumonia … which is common with severe burn victims.

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Alright, I’ll get off my soapbox and share some safety stuff with you …

Roll Bars

A. A 4-point roll bar with plates bolted to or welded to thin sheet metal in unibody type cars … adds a very small level of protection. I believe more to satisfy insurance companies than to protect the driver. Car owners add them thinking they are getting a degree of safety that really doesn’t exist … and then have a false sense of security when driving in races, or race like conditions.

B. A 4-point roll bar that mounts to actual frame structure, does offers a higher degree of crush protection in the event of a roll over or impact to the roof.

C. The more footprint points the roll bar or cage has, the stronger it will be. The more of these points that actually connect to frame structure, the stronger it will be.

D. A 4-point roll bar with 2 extra struts that connect the main hoop to the subframe connectors in unibody type cars, makes a difference. Look at the red bars in the attached photo at the bottom of this post.

E. A 4-point roll bar with 2 extra connector struts … with the 2 rear bars attaching to real rear subframe … is significantly better.

F. A 4-point roll bar with 2 extra connector struts … with the 2 rear bars attaching to real rear subframe … in an X-brace fashion … is substantially better.

G. Building a 6-point roll bar with 4 rearward bars … 2 straight & 2 in an X-brace … both attaching to real frame … is as good as you can build without adding door bars or a cage. There are various designs. I think some are safer than others.

H. Door bars are one the best additions you can add to a roll bar for safety & performance … if you don’t mount them too low. It supports the roll bar from “folding” with the added bonus of strengthening the chassis for improved* performance. *Maybe a discussion for another thread sometime.

I. An added bonus, if you didn’t mount them so low they’re worthless, is door bars add protection in side impacts, when someone runs a red light & crashes into your door, or the passenger door where your loved ones ride.

J. For Pete’s sake … don’t install a roll bar so close to the driver’s or passenger’s head … that they hit it in an impact … UNLESS you are ALWAYS going to wear a helmet … including on the street. Guys have died from moderate wrecks on city streets, when their unprotected head hit the roll bar and split their head open. In those type of typical auto wrecks, they would have been better off to have no roll bar. Please don’t use this as an excuse to not have one. Just install it with this in mind.

Material Matters:

K. Most roll bars & cages are made with inexpensive seam welded mild steel. Mild steel grades commonly vary from 1010 to 1030. The higher the number, the stronger it is. Most seam welded tubing commonly available is 1010 or 1012, the cheapest with the least strength. But 1018 is available, for slightly more money, if you look for it. Buying a roll bar … ask the manufacturer what they use.

L. DOM stands for drawn over mandrel. It is a better process for manufacturing round tubing, working with the grain of the steel & leaving no weak seam. It is still mild steel … but because the process costs more, manufacturers use higher grades ... typically 1018 to 1026. Most stock car cages are made from this. A small percentage are made with chromoly. Because of the constant crashes & repairs in oval track racing, these racers & chassis builders like that the mild steel DOM bends easily creating localized crush zones. Personally, I don’t want a roll bar over my head as a crush zone.

M. Stainless steel tubing is similar in strength to DOM mild steel. In racing, we use it on bumpers & nerf bars that we WANT to bend on impact. We use stainless, instead of DOM, only so we don’t need to paint it or chrome it. We tig weld it & bolt it on.

N. 4130 Chromoly is the strongest option of commonly available & affordable tubing materials. OMG! Chromoly is SO MUCH STRONGER than mild steel, DOM or stainless steel … it’s hard to compare them. NHRA understands this & requires mild steel bars to be 1-3/4” x .134” wall or 4130 Chromoly at 1-5/8” x .083” wall … and the Chromoly is STILL STRONGER. All pro level drag cars are made from Chromoly for this reason. Chromoly is so strong, that often when a car wrecks, instead of crushing, it spreads the load over the whole car … and therefore the entire chassis “bows.”


Roll Cages:

O. When you up your game to a well designed roll cage with 8, 10, 12 or 46 points, you just increased the safety factor by triple, and the chassis rigidity too. Again, in unibody type cars, you will want it to connect to real frame structure as much as possible. The increase in torsional rigidity ... and the performance gains make this a double win.

P. The optimum set up, is to make the cage out of Chromoly for the best driver & passenger protection … and make the front & rear bars out of DOM for crush zones in the event of front or rear impacts.

Other safety components:

Q. If you guys want to discuss any of this, I’d be happy to share with you insight on fire extinguisher systems, full containment seats, head & neck supports, suits, helmets, etc. Let me know.

As the Watch Commander used to say on Hill Street Blues, "Be safe out there."

...

[Flash68]

The sport of Pro Touring … where drivers compete in AutoX, real road courses & fast events like the Silver State Challenge … are just asking for someone to get killed or disabled … because there are less rules. Don’t let the lack of rules guide your safety.

Could not agree more Ron. :thumbsup:

[Sieg]

Thank you Ron.

Great information.

IMO - The modern day PT car with 500-650+ hp are really lacking cockpit integrity considering the acceleration and speeds they are capable of and obtaining.

Do you have any knowledge pertaining to subframed Camaro's regarding a cage's level of chassis stiffening with and without subframe connectors?

[Ron Sutton]

Sieg,

I thought I saw saw engineering numbers on this site after someone installed frame connectors. But, I don't have anything quantitative. I got to see a Pro/Stock car on GM's test equipment, simulating forces, to see where it flexed & didn't ... which was very helpful ... but nothing with stock bodied cars.

I know the frame connectors, when welded in, add a degree of stiffness. And when the roll bar utilizes braces from the main hoop ... under the cross bar ... attached to frame connector ... the roll bar is much better prepared to withstand roof impacts ... than compared to just welding plates to the sheet metal.

Running door bars at the correct height and effectively making this an 8-point roll bar is going to raise the level of safety while improving the torsional rigidity of the chassis quite a bit.

I just can't put a number on it.

[Sieg]

Thanks Ron. :thumbsup:

[Ron Sutton]

I'd like to add ...

If i were installing a 4 or 6 point roll bar without door bars ... or a 4, 6 or 8 point roll bar with door bars ... but not a "roll cage" ... I would use 4130 Chromoly for ultimate strength ... and mount to as many frame structure points as I could.

[Track Junky]

Ron, I'll be using fiberglass doors for next season. Would love to chat about door bars.

[Ron Sutton]

Ron, I'll be using fiberglass doors for next season. Would love to chat about door bars.

Gotcha. Do you have a roll bar now without door bars?

If yes, post some info on it ... brand, diameter, wall thickness, material, bolted or welded in ... and photos would help.

---------------------------------------------------------------

A couple of quick tips:

a. You typically want it to connect to the main hoop at the bend, in line with the bar behind the seats. But this is just a starting point.

b. Ideally, you want to run the lower mount as far forward as you can, to create a wide "truss-like" footprint.

c. After you mock up some plastic sprinkler pipe at these two points ... we need to see if we run into "packaging problems."

d. We want to make SURE the door bars don't interfere with your ability to steer the hot rod. because seat height, door bar height & driver height all play a role ... i never know until we mock it up.

e. Often times, the bar is too close into the driver's seat (passenger too) and putting a bend in the door bar, with the curve "out" ... provides more driver cockpit room.

f. At the other end, we simply need to make sure it doesn't interfere with your feet or pedals.

g. Don't put a downward bend in it if you can avoid it. Especially in a track car. The improved strength & safety of having the bar at the right height outweighs the inconvenience of climbing over the bar.

h. I like to use 4130 Chromoly for door bars, regardless of what the main hoop is main of. Chromoly welds to mild steel just fine & the increased driver & passenger protection is worth the small difference in tubing cost.

i. I typically use the same size of tubing for the door bars as the main hoop ... 1-3/4" or 1-5/8". An exception would be if we need to go down 1/8 or 1/4" for clearance purposes. If you use 1-3/4" or 1-5/8" diameter Chromoly ... .083" wall is good. If you drop down to 1-1/2" diameter ... bump the wall thickness to .095"

When you post the info & photos we'll be able to discuss more.

[Simmo]

Hi Ron,

With reference to point g. - what are you're thought's on triangulating the downward bend a in this image? Seems like a good compromise strength/ergonomics.

BTW: Really been enjoying reading - and re-reading your posts! :headscratch:


http://www.griggsracing.com/gallery/69GR350/Roll%20Cage%20Main%20hoop%20door%20bars.jpg

[Ron Sutton]

For chassis strength, the triangulation of the door bar makes up for the bend & then some, making it stronger.

But often the door bar being lower doesn't offer as much side impact protection in a crash. I say "often", because it all depends on the height of the bar versus the people in the seats.

Ultimately, for safety, you want the door bar to prevent things ... cars, telephone poles, ends of concrete barriers, etc ... from coming in & hitting the driver or passenger in side impacts.

Stock Car style bars with uprights & 1/8" plate work best & Pro/Stock X-braces work well too, but both require people to "crawl in". For single down bar with braces, I prefer the structure & placement in this photo.

[bret]

Couple of items I'd like to chime in on...

* Ron's comments materials and construction are all on point...can't disagree with any of them.

* The TigerCage is certified up to 175MPH by the ECTA, and has been since 2010.

* The current lack of NHRA/SFI certification for the TigerCage is a reflection of the fact we've been 100% pursuing our shock program at the expense of the TigerCage program. Its a matter of dollars...there's more of them in shocks than cages. If/when the shock program levels out I'll get back on the TigerCage program.

* The comment about welding a nice rigid rollbar/cage structure to a thin floorpan is especially on point. The TigerCage system integrates with the structural strength points of the specific model it is designed for in at least two different planes. That way one set of fasteners is always in shear instead of just tension.

* we use 304L stainless for several safety reasons:
1. in addition to the tangible material strength properties, austenitic stainless like 304L has the ability to deform in a predictable manner upon impact. This means it will tend to absorb crash impact energy instead of transferring it to the driver. In addition, once deformed it will take a set with a significantly increased yield [bend] strength. [think work hardening without the brittleness]
2. by avoiding a coating we avoid any possibility of the installer covering up an incomplete/inferior weld. Ever wonder whats under that nicely smoothed "weld" joint?

* the aesthetic and convenience features of using stainless are merely a happy coincidence.

More tech info on the TigerCage here: http://www.ridetech.com/store/tigercage/

I will also say that for the guy who has the talent, ambition, and resources to design and construct a PROPER rollbar/cage for their car...the TigerCage is likely not the most efficient solution. For the person who lacks any of the above...it might be a viable alternative.

Glad to see the interest in this level of info here!

[sik68]

The sport of Pro Touring … where drivers compete in AutoX, real road courses & fast events like the Silver State Challenge … are just asking for someone to get killed or disabled … because there are less rules. Don’t let the lack of rules guide your safety.


Could not agree more Ron. :thumbsup:

:clap: I second DG; what a quote.

[Chassisworks]

Its going in a gen II Camaro. Thanks in advance for the feedback.

If I can throw our name in the hat here, you might consider checking out the Chassisworks options (http://www.cachassisworks.com/c-248-roll-bars-roll-cages.aspx). Chris Alston has been designing, installing, and manufacturing safety devices since the '70s. He created the first NHRA legal door swingout. Chris was on the safety board that BECAME the SFI Foundation board, and is still involved from time to time. So, we know a little about building cages.

We are going to be making an Exact-Fit cage for the second gen Camaro. If you're in NorCal and looking to have someone install a cage in your car, you might check out THIS LINK (http://www.cachassisworks.com/Attachments/DataSheets/CamaroRollCage_DS_WEB.pdf)then give me a call. Exact-Fit cages are available in 1-5/8" ERW and 4130, or 1-3/4" ERW or DOM. Roll bars are available in 1-3/4" ERW.

It will fit like the image below, only in a different body. Currently, we are working on the 67-68 Mustang version. Whatever car shows up next that wants one is what we will build.

Carl

http://www.cachassisworks.com/site_images/vehicles/Camaro/Camaro69_SEMA2012/gStreetCamaro1_headliner_at.jpg

[Ron Sutton]

Carl,

You mentioned cages available in 1-5/8" ERW and 4130, or 1-3/4" ERW or DOM. Can someone custom order a 1-3/4" 4130 cage?

Same question for the Roll bars, available in 1-3/4" ERW. Can someone custom order a 1-3/4" 4130 roll bar?

.

[Chassisworks]

Carl,

You mentioned cages available in 1-5/8" ERW and 4130, or 1-3/4" ERW or DOM. Can someone custom order a 1-3/4" 4130 cage?

Same question for the Roll bars, available in 1-3/4" ERW. Can someone custom order a 1-3/4" 4130 roll bar?

Hi Ron,
My instinct is to say 'no' but it would really depend on the wall thickness.

We don't have a mandrel to bend 1-3/4 x .083 and therefore don't stock the material. If a different wall thickness was required, say .120, then we could probably make it. This is one of those 'anything is possible if you're willing to pay for it' situations.

If you have a specific project in mind, use the Batphone and talk to Chris.

[Ron Sutton]

Hi Ron,
My instinct is to say 'no' but it would really depend on the wall thickness.

We don't have a mandrel to bend 1-3/4 x .083 and therefore don't stock the material. If a different wall thickness was required, say .120, then we could probably make it. This is one of those 'anything is possible if you're willing to pay for it' situations.

If you have a specific project in mind, use the Batphone and talk to Chris.



My Batphone is out for repair. :lol: :rofl:
I enjoyed talking to Chris the other day & catching up. You guys have some cool stuff going on.


I asked ... because I feel more safety is needed in the PT world. Like I said in post #10 of this thread ...

In race cars, I’ve been on fire, been upside down at 177 mph, hit walls so hard I’m lucky to be alive & broke my back in 1991 … almost didn’t walk again. This stuff is serious.

If guys are building PT cars to be like race cars … and drive them hard in race situations … then they need plan for race level safety measures. The sport of Pro Touring … where drivers compete on some fast AutoX tracks other than GG, fast 2+ mile road courses & high speed events like the Silver State Challenge … are just asking for someone to get killed or disabled … because there are less rules.

Don’t let the lack of rules guide your safety decisions.

I'm not in my car. I don't care what the rules are. I designed it to protect me, my buddies Mike Maier & Benny Moon that will compete in it some and my daughter Nikki when she & I run Silver State.

The PT car I'm building for myself has a full roll cage out of 1-3/4" x .095" 4130 Chromoly ... fitted out tight to body for max protection ... with several main hoop supports & a roof bar. The door bars are the same 1-3/4x.095 4130 chromoly ... braced two ways ... because I'm not fond of stuff (telephone poles, other cars, concrete barriers) coming in through a thin door skin.

The front & back cage bars are made of DOM mild steel tubing ... in different diameters & wall thicknesses ... just strong enough to achieve my chassis rigidity goals ... but designed to crush digressively in a front or rear impact.

For the record, we can build anything in our shop but I do not want to be in the roll bar or cage business.

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Guys are installing 4-point roll bars welded to sheet metal ... and going 130mph on the sweeping corners of Haulin' Ass America Speedway ... with a false sense of security. People die in wrecks at slower speeds than that.

I've known Chris Alston since 1979, consider him a good friend & the best designer of drag race cars, cages, suspensions, etc. He an innovator & taught me a lot. If guys were putting full 12-point cages in their cars, I wouldn't have as much concern.

But many guys struggle with the decision on putting a 4-point or 6-point roll bar into these cool, bad ass, high powered, G-pulling, mean machines. :confused59:
My thoughts are ...if PT guys were educated on this stuff ... and there was a strong, lightweight, effective roll bar available, the smart guys would buy it.

I think the 4/6 point roll bar needs to be:
a. All 1-3/4" x .095" 4130 Chromoly tubing
b. Tight fitting to the body as Chassisworks does
c. Have a cross bar tube behind the seats
d. Two tubes to the rear subframe (not floor)
e. Main hoop weld to plates that weld to the floor of unibody cars & the frame of full frame cars.
f. With two tubes that meet at the intersection of the main hoop & cross bar, welded to the the subframe connectors on unibody cars. Just like Chris designed over 30 years ago.


The better, stronger, safer, less chassis flex version, would be a 6/8 point roll bar ... same as above ... plus:
g. Two door bars, tight fitting to the door for increased cockpit & driver room, that run from the main hoop to as far forward as they can.

Guys ... Chassisworks makes the strongest hinged door bar for easy access. But I suggest you go solid & weld the door bars in. If you can't get your fat ass over the door bar ... Beau Duke ... maybe you shouldn't be driving 120+mph on race tracks. :stirthepot:

Place the door bar high enough that it protects you ... and the passenger you're responsible for ... in case of a side impact. Refer to the photo below to see what I mean about height.


The best "roll bar" would include:
h. Two more tubes, forming an X-brace behind the main hoop to add a TON of strength & crush resistance to the main hoop ... for better driver & passenger protection in a roll over crash.

Guys ... look at the blue mustang below & see where the roll bar pushed through the sheetmetal floor ... and the roof & roll bar crushed. I'm starting to like you guys & don't want this happening to you. The added chassis rigidity would pay performance dividends too, making the car more responsive to tuning changes, react quicker, & utilize the car's power & speed better.


Carl, I can not say with any certainty that PT guys would buy a stronger roll bar made out of 1-3/4" x .095" 4130 Chromoly ... but I know that is what I would sell & recommend.

[Sieg]

Video link isn't working for me......

Primary concern on street with roll bars.......no helmet and head injuries. Thoughts?

[garickman]

Video link isn't working for me......

Primary concern on street with roll bars.......no helmet and head injuries. Thoughts?

I guess I will throw my hat in the ring when it comes to street cars with a roll bars or a roll cage. Let me first start by saying I have no experience at all with roll bars or roll cages nor have I ever seen a vehicle in any type of accident that was equipped with such a device. I have however been on the scene of somewhere in the neighborhood of 200-250 motor vehicle accidents and about 25 of those being fatal.

I have seen injuries in person ranging from cuts and bruises to complete decapitation, and I can assure you of one thing. It is impossible to predict what injuries may or may not occur during an accident. I always see people on these forums with the same argument about roll bars and head injuries. It is possible you could suffer severe head trauma from a roll cage that you may not have suffered if the vehicle did not have said cage. On the flip side of that same coin, it is just as possible you may be involved in a violent roll over accident in which that roll bar may have saved your life. It's a coin toss of how effective or how much damage a roll cage would be in the event of a street collision.

[Ron Sutton]

Video link isn't working for me......

Primary concern on street with roll bars.......no helmet and head injuries. Thoughts?

Thanks for catching the video link. I couldn't make the video work either, so I changed the wording & added the blue Mustang photo at the bottom.

As far as the roll bar being installed too close to the driver's head, I copied & pasted my point "J" from my original post #10 on this thread.



J. For Pete’s sake … don’t install a roll bar so close to the driver’s or passenger’s head … that they hit it in an impact … UNLESS you are ALWAYS going to wear a helmet … including on the street. Guys have died from moderate wrecks on city streets, when their unprotected head hit the roll bar and split their head open. In those type of typical auto wrecks, they would have been better off to have no roll bar. Please don’t use this as an excuse to not have one. Just install it with this in mind.



.

[Chassisworks]

Ron,
Our theory with offering the cage in 1-3/4 x .120 wall DOM is that is the requirement for most national road race organizations. If I have heard Chris say this once, it's been 50 times (and I'll paraphrase so I don't get banned for swearing): 'Making these cars handle like race cars without adding adequate protection is stupid, anyone who thinks that they and the car will survive a rollover is on dope.'

Or something to that effect. This is why our gStreet Full Frame comes STANDARD with a six-point, weld-in roll bar.

I'll leave it up to you guys to hash out diameters of tubing. I don't pretend to be a super smart engineer; I just work for one. He let's me touch the computer because I tend to be less abrasive. :stirthepot:

[Ron Sutton]

Hi Greg,

I guess I will throw my hat in the ring when it comes to street cars with a roll bars or a roll cage. Let me first start by saying I have no experience at all with roll bars or roll cages nor have I ever seen a vehicle in any type of accident that was equipped with such a device. I have however been on the scene of somewhere in the neighborhood of 200-250 motor vehicle accidents and about 25 of those being fatal.
Oh my gosh, that has to turn your stomach. I've been on the scene at a few at the race track. Which is part of what makes me passionate about safety.


I have seen injuries in person ranging from cuts and bruises to complete decapitation, and I can assure you of one thing. It is impossible to predict what injuries may or may not occur during an accident. I always see people on these forums with the same argument about roll bars and head injuries. It is possible you could suffer severe head trauma from a roll cage that you may not have suffered if the vehicle did not have said cage. On the flip side of that same coin, it is just as possible you may be involved in a violent roll over accident in which that roll bar may have saved your life. It's a coin toss of how effective or how much damage a roll cage would be in the event of a street collision.

No disrespect at all ... because you do a tough job & see a lot of crashes on the street. I have a LOT of experience with race car crashes. A lot. :soapbox:

A properly designed & installed roll bar or cage is a sure thing for added driver safety ... because if belted in the seat with a 5-point harness ... the driver can not stretch far enough for their head to come close ... let alone hit it. In the car I'm building for myself, with driver & passenger strapped in, the nearest tube is 5" away. (I always allow 2" for seat belt stretch) :knokwood:

If the builder puts the roll bar too close to the seat ... or the seat too close to the roll bar ... that is dangerous. Otherwise, the only danger is if they don't wear their seat belt. (dumba**) Then the injuries can be worse, as I outlined in point J. :sieg:

When safety features debut or new safety measures are mentioned ... many of us voice concerns as to using them. I remember my Dad saying, "I'm not wearing seat belts. They can trap you in the car." Today seat belts save so many lives.

But if you installed seat belts so they wrapped around your neck they would probably kill you too. :sarcasm_smiley:
All safety items need to be installed correctly. :thumbsup:

When HANS devices came out, a lot racers said, "I won't wear one. I can't turn my head as far & see well. I may cause a crash." Complete BS. They have saved so many lives in head on impacts. Now drivers just wear then & don't give them a second thought.

My brother in law is a Sheriff down in Riverside and some of the stories he tells from vehicle crash scenes are horrible. I'll bet you have seen some simple crashes where people died needlessly because they weren't wearing their seat belts. :(

I know I enjoy discussing the "how to go faster" part of cars more. I just don't want to see anymore people die needlessly ... so I speak my mind & share my experiences when it comes to "let's be smart about this" part of car building. :cheers:

[Ron Sutton]

Ron,
Our theory with offering the cage in 1-3/4 x .120 wall DOM is that is the requirement for most national road race organizations. If I have heard Chris say this once, it's been 50 times (and I'll paraphrase so I don't get banned for swearing): 'Making these cars handle like race cars without adding adequate protection is stupid, anyone who thinks that they and the car will survive a rollover is on dope.'

Or something to that effect. This is why our gStreet Full Frame comes STANDARD with a six-point, weld-in roll bar.

I'll leave it up to you guys to hash out diameters of tubing. I don't pretend to be a super smart engineer; I just work for one. He let's me touch the computer because I tend to be less abrasive. :stirthepot:

I've known Chris for over 30 years.

MAN ... did you clean his statement up.

You probably needed industrial strength cleaner & a clean suit ... to get it that "polite." :rofl: :rofl: :rofl: :rofl: :rofl:


.

[DaleTx]

This is great discussion here... thank you Ron, and the others for sharing your views on safety, and for throwing out practical solutions on how a pro touring type car can be made safer.

I am the guy that has built a pro touring car with high horsepower, and loves to get out on a fast road course and push the car to it's limits (130 mph on the sweeping curves of road-course america :))... like lots of the guys on here. After reading this thread I have made the decision to improve the safety of my car.

Right now my car is set up with a welded in DSE 4-point roll bar and G-Force 5 point safety harnesses... I plan to modify my roll bar per the design shown here. I will use 1-5/8" chromoly tubing with welded connections.

http://i1048.photobucket.com/albums/s364/daltol/6-pointwithredconnectorstruts_zps51648f20.jpg (http://s1048.photobucket.com/user/daltol/media/6-pointwithredconnectorstruts_zps51648f20.jpg.html)

Not only will I improve safety... but the chassis will be stiffer... win win.

:lateral:

[Ron Sutton]

This is great discussion here... thank you Ron, and the others for sharing your views on safety, and for throwing out practical solutions on how a pro touring type car can be made safer.

I am the guy that has built a pro touring car with high horsepower, and loves to get out on a fast road course and push the car to it's limits (130 mph on the sweeping curves of road-course america :))... like lots of the guys on here. After reading this thread I have made the decision to improve the safety of my car.

Right now my car is set up with a welded in DSE 4-point roll bar and G-Force 5 point safety harnesses... I plan to modify my roll bar per the design shown here. I will use 1-5/8" chromoly tubing with welded connections.

Not only will I improve safety... but the chassis will be stiffer... win win.

:lateral:

Yes it will. The more rigid chassis structure makes the car faster, more responsive & tunable.

[glassman]

Ron, regarding that "common" drawing from two posts above, what is the point of diminishing return regarding lowering the triangulation from the door entry?

in other words, how low can it go, mostly you want the safety first, but entry dynamics come into play from the pro-touring vs racing side. I've seen alot of them run parallel to the running boards, which only help, i believe, in torsional rigidity, but not rollover protection. Is that part of the cage designed to help keep the main hoop from crushing?

I noticed its at the height of the harness bar, how much lower can it go while still retaining most of its integrity, while still being able to climb in ok (think wifey). 90% of my car is built for street, but track 10% of the time, i dont want to sacrifice safety, but ????? how low can it go?

thanx, Mike

[Sieg]

I've known Chris for over 30 years.

MAN ... did you clean his statement up.

You probably needed industrial strength cleaner & a clean suit ... to get it that "polite." :rofl: :rofl: :rofl: :rofl: :rofl:


.
That would be "PC Gap Spray" around here. :D

[Ron Sutton]

Hey Mike,

Thanks for putting your name in the post. I always feel weird referring to someone's "street name". :lol:

Ron, regarding that "common" drawing from two posts above, what is the point of diminishing return regarding lowering the triangulation from the door entry?

in other words, how low can it go, mostly you want the safety first, but entry dynamics come into play from the pro-touring vs racing side. I've seen alot of them run parallel to the running boards, which only help, i believe, in torsional rigidity, but not rollover protection. Is that part of the cage designed to help keep the main hoop from crushing?

I noticed its at the height of the harness bar, how much lower can it go while still retaining most of its integrity, while still being able to climb in ok (think wifey). 90% of my car is built for street, but track 10% of the time, i dont want to sacrifice safety, but ????? how low can it go?

thanx, Mike


Well ... what it was designed for originally ... could be open to interpretation. I can only share with you my experience & points of view from that experience.

For safety purposes, it does two key things, by priority:

1. It is to prevent mean things from coming into the car & killing you. Unfortunately, I know from first hand experience where guys died from side impacts with trees, telephone poles, ends of concrete barriers, other cars, etc. So it needs to come up high enough to protect the driver & passenger's bodies from impacts.

Look at the illustration I attached here ... from the NHRA rule book ... and see where the driver is in relation to that door bar. The door bar acts as a barrier between the driver & passenger's bodies and "stuff." If that door bar is 1-3/4" x .095" Chromoly ... it can take a hard hit & bend a few inches. In faster, harder side impacts .. the object may very well come in much farther, but the tube will help slow the object. This can mean the difference between broken bones & death.

So, to answer your question about how high it needs to be, varies with your seat mounting. The key is to make sure the Chromoly tube is a barrier for the driver & passenger's torsos when they are in the seat. I like to make sure it is protecting the majority of their body, as shown in the illustration. This varies with seat height, angle & placement ... and is usually lower than this drawing.

2. It is the only thing preventing the roll bar from folding in the middle in a hard flip or roll over. It turns a triangle into a double triangle, sort of like making it a truss.

But I don't set the height for this role. I set as outlined in #1.

[glassman]

yep makes total sense. its almost as if i will be "tailoring" it to fit. Which, i guess, gave birth to the word "custom"....as one size does not fit all...this is up next on the car once the tuning and clutch are sorted out. I have a "hoop" from Alston, but need the rest of the components.....

[Ron Sutton]

yep makes total sense. its almost as if i will be "tailoring" it to fit. Which, i guess, gave birth to the word "custom"....as one size does not fit all...this is up next on the car once the tuning and clutch are sorted out. I have a "hoop" from Alston, but need the rest of the components.....


When you say it's from "Alston" ... is that Chris Alston's Chassisworks or the old Alston Race Car Engineering brand that was bought out when Chris' brother Tom's company went defunct long ago?


I ask, because Chris Alston Chassisworks builds the best roll bars. The use a higher grade of steel, because Chris understands steel. And the roll bars & cages fit tighter to the body which provides more room for people to move around... especially the driver who can get quite busy in the cockpit.

[Chassisworks]

Regarding the placement of the main hoop: Per NHRA rules the main hoop of a roll BAR must be within 6" of the helmet, vertically and horizontally, but it does NOT have to be that close when you have a roll CAGE. I do not know if this is the case with any other sanctioning bodies (NASA, SCCA, et al.) but thought it worth a mention.


When you say it's from "Alston" ... is that Chris Alston's Chassisworks or the old Alston Race Car Engineering brand that was bought out when Chris' brother Tom's company went defunct long ago?

I ask, because Chris Alston Chassisworks builds the best roll bars. The use a higher grade of steel, because Chris understands steel. And the roll bars & cages fit tighter to the body which provides more room for people to move around... especially the driver who can get quite busy in the cockpit.

:thankyou:

Thanks Ron! There are definitely differences. The old Alston name is still around as 'Alston Race Cars,' mostly selling parts Chris designed in the '70s. Interestingly, it was sold last year and purchased by one of our competitors.

[Sieg]

Interestingly, it was sold last year and purchased by one of our competitors.
Hope that doesn't create any unnecessary brand maintenance. :_paranoid

[Chassisworks]

Hope that doesn't create any unnecessary brand maintenance. :_paranoid

We shall see. So far the only thing of note is a bunch of our parts ended up in one of their ads on another car website. We were pretty stoked about the free exposure.

:topic:

[Ron Sutton]

Regarding the placement of the main hoop: Per NHRA rules the main hoop of a roll BAR must be within 6" of the helmet, vertically and horizontally, but it does NOT have to be that close when you have a roll CAGE. I do not know if this is the case with any other sanctioning bodies (NASA, SCCA, et al.) but thought it worth a mention.

Yes. When we used to install roll bars a lifetime ago, we mocked up the driver & set them 4" away from the roll bar main hoop. Didn't want the driver's head hitting the bar ... even with a helmet. In PT cars it needs to be 5" in my opinion.

:thankyou:

Thanks Ron! There are definitely differences. The old Alston name is still around as 'Alston Race Cars,' mostly selling parts Chris designed in the '70s.
Yup. Yup. Exactly.


Interestingly, it was sold last year and purchased by one of our competitors.

Hmmm. Weird. Why would a company want to use the old Alston Race Cars name.

[glassman]

When you say it's from "Alston" ... is that Chris Alston's Chassisworks or the old Alston Race Car Engineering brand that was bought out when Chris' brother Tom's company went defunct long ago?


I ask, because Chris Alston Chassisworks builds the best roll bars. The use a higher grade of steel, because Chris understands steel. And the roll bars & cages fit tighter to the body which provides more room for people to move around... especially the driver who can get quite busy in the cockpit.




Chris Alston Chassisworks, bout three years ago, problem is they (the people i bought the roll bar from, not CA)can't find all the parts. The guy had a 2nd gen and sold it....
The guy i'm having do the install / welding use to work there. He opend up a company here in the east bay called 'East Bay Metal fab", ....

mike

[Ron Sutton]

Chris Alston Chassisworks, bout three years ago, problem is they (the people i bought the roll bar from, not CA)can't find all the parts. The guy had a 2nd gen and sold it....
The guy i'm having do the install / welding use to work there. He opend up a company here in the east bay called 'East Bay Metal fab", ....

mike

Okie Dokie. The main hoop should fit good then.

[TheJDMan]

Even today I fondly remember watching Alan in that red and white Camaro hole shot the competition. Damn he was quick on the lights!!!

Ron,
I have a question regarding the roll bar braces that you show in red which connect to the subframe connectors. The SCCA requires a diagonal bar that intersects the horizontal seat belt bar and attaches at the base of the RH hoop mount up to the corner of the hoop behing the drivers head. How would one incorporate both of these bars?

[Ron Sutton]

Even today I fondly remember watching Alan in that red and white Camaro hole shot the competition. Damn he was quick on the lights!!!

Ron,
I have a question regarding the roll bar braces that you show in red which connect to the subframe connectors. The SCCA requires a diagonal bar that intersects the horizontal seat belt bar and attaches at the base of the RH hoop mount up to the corner of the hoop behing the drivers head. How would one incorporate both of these bars?

I have seen it done two ways. I edited the drawing to show both ways.

The image on the left is version #1, where the diagonal bar & the subframe bar basically make a x-brace on the passenger side.

The 2nd image is version #2. I prefer this version, as the diagonal bar connecting to a 2"x3"x120" wall subframe connector (fully welded to the floor, front & rear frames) will be a tick stronger & lighter. But technically it doesn't fit the letter of the rule.

I asked the guy who had done his car this way, and he said he simply ran the design past his local SCCA tech director before building it and got an OK. So, if you go this route, I'd get approval first.

[feeble]

If I understand the SCCA rules correctly, isn't the diagonal bar supposed to be continuous?

Here is my car:
http://www.mustangiitech.org/gallery2/d/12298-2/SAM_1173.JPG

Several things I'm not real clear about yet are:

1) Height of the harness bar relative to the cutout in the seats (obviously I'll need to figure out what seats I'm going to use.)

2) The harness bar that came with my kit has bends on both ends so that it would not be in the same plane as the hoop when installed. Wouldn't it be better to have it in the same plane?

3) The bars that Ron shows in red were included with my kit but will not work in my car as the subframe connectors connect to the suspension pickup point directly underneath where the main hoop attaches to the floor. Any thoughts for an alternative location?

Thx!

[Damn True]

For both NASA and SCCA the diagonal is supposed to be uninterrupted, the harness bar is the one that should be segmented.


FIA as well if memory serves but it's been a long time since I reviewed those rules.

[Tuske427]

Wow, sure am glad I stumbled across this post. I'll be adding those "red" bars to my rollbar to tie into the subframe. Thank you, everyone, for sharing this info.

-Brendon

[Tuske427]

"red" bars added. It's like the "version 1" based on Ron's attached images posted earlier.