STMPO Rollbar

[TURBO2GO]

I have been working with Ross in the creation of a real rollbar for the NSX. After discussion with many people who build cages and race cars, I have come to the conclusion that the harness bars we are using have real questionable safety value. In a rollover you are pretty much dead or paralyzed if the roof caves, and there is zero additional safety support added by the bar itself. In fact it can become a dangerous object in the cabin in a crash.

On the original suggestion of John@microsoft, I started for a true rollbar with a main hoop. I looked into various aftermarket rollbars, and after seeing how they work, I am seeing them more as a show item than a real safety item.

It is very difficult to get a real rollbar in the NSX. Ross was insistent that the unit tie to the frame rails, the only strong part of the car. There is extremely limited space in the car, but he took a lot of measurements and was able to come up with a way of attaching the main hoop to these rails. The other attachment points is the rear strut locations. Using a STMPO RSTB and attaching bars that go through the rear glass and attach to the main hoop inside the car.

The trade for the extra strength is that the rear glass will have to be changed to a lexan one for the two support bars to attach to the main hoop. The plus is.... there is no carving up of the car's interior for a full cage, the rollbar will have an integrated harness bar, and the chassis will be made even more rigid.

This is what I feel is the first real product that is a compromise between a full cage and staying stock (which is not what I want to do). Ross has made some drawings for me, and will start working on this soon. This way I can have rollover protection, the additional protection of a harness and HANS or similar device if so desired.

Ross has done an awesome job with other chassis parts and I think this will be the best one yet. For guys that track their cars but are not willing to cage their car, this should be a huge step forward in safety. Here is a drawing that Ross did by hand a few days ago. The blue is the RSTB, the red are the support bars, the brown is the main hoop inside the car attached to the frame rails (NOT THE FLOOR).

I hope this product appeals to some of you and we give Ross some support.

 

[CL65 Captain]

Dave,

TIME OUT. :biggrin:

Do you want a street car or a race car? My last student had a beautiful 993 that he attended about a dozen HPDEs with. Like you, he decided he wanted to start looking into safety items. He realized that the only way to do that is the complete system, in other words, a full blown race car with all the safety items that come with it. IMO your best bet is to find someone who is getting out of club racing and has a complete sorted out race car that you can step right into....

My student bought this beautiful 85 911 for under $40k. And the 993 still sits in the garage for the weekends he's not at a HPDE. Said it was the best thing he has ever done.

PS: It was not only quick, but a blast on the track. In competent hands - this 235 hp car would absolutely smoke me on the track.

As I always do, once during the weekend I like to chase my student so they have something to "take home" and also so they can see where their line is compared to where they think their line was.

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[CL65 Captain]

PS: Dave & Ross....

Don't get me wrong, I think this would be an awesome product....

Just thought a time out was in order to think about race car vs street car. I was going down this same path before I realized it was too much of a compromise. It was turning into a pseudo street car and pseudo race car, which did neither correctly. :biggrin:

 

[CL65 Captain]

PS: PS: Dave....

here is an example

http://forums.pelicanparts.com/pors...ck-race-car-grand-prix-white-plus-extras.html

$29k obo. :biggrin:

 

[HIJACKER]

Another thing to consider, a full rollcage (or similar) in a street driven car is also VERY unsafe. On the street, you're not wearing a helmet and if your head impacts against one of those bars, you're toast.

 

[StmpoRaceProducts]

I think this will help visualize it.....

The bar would be a safety piece bolted to current STMPO RSTB's...

Main hoop with harness bar with rear diagnonal members.

Regards

 

[StmpoRaceProducts]

Another thing to consider, a full rollcage (or similar) in a street driven car is also VERY unsafe. On the street, you're not wearing a helmet and if your head impacts against one of those bars, you're toast.

This was also taken into account during measurements....

Regards

 

[Hrant]

It is always refreshing and encouraging to see products in their development.

I am not a structural engineer, but don't you need to have a cross bar from one of the B piller top corners to the opposite lower moutning point? Also, isn't the weakest point on the roof line the A pillar - even in a coupe per your illustration?

If this is for more than just HPDE, then perhaps looking at some specs by racing sanctioning associations might be helpful. Perhaps you have taken that into consideration already :wink:

 

[TURBO2GO]

Dave,

TIME OUT. :biggrin:

Do you want a street car or a race car? My student bought this beautiful 85 911 for under $40k. And the 993 still sits in the garage for the weekends he's not at a HPDE. Said it was the best thing he has ever done..

Jim, as you said yourself, you have been doing 10-12 HPDE's a year, for like 6 years? Perhaps 70 or so track events, maybe more. You just posted a video where you were very lucky as someone in front spilled fluid on the track. Your safety gear, and I know we laughed about it but... it's "the cheapest helmet I could find".

I just am not willing to take the same risk level that you are. I had a talk with Liquid about this the other day... who now is into a Z06 and sold his NSX but comes to DE's with me. He is a very wise guy with a family and he too is very concerned with safety. There are shades of gray when it comes to safety. Not everything is black or white. There are things in between buying a full race car or doing absolutely nothing.

I do not want a dedicated race car. I don't want a trailer, a truck to pull it with, or a third car. But I still care about safety. When I went to buy a helmet, I bought a $950 Arai. I feel that a HANS or something that protects my neck is IMPORTANT. I cannot do this without a harness, I cannot do a harness without a harness bar, and I will not do a harness bar without rollover protection of SOME SORT. This item, is ideal for me and people like me. In fact, YOU should be getting one of these probably more than any of us. Perhaps the next spill will not go as well (Heaven forbid).

Another thing to consider, a full rollcage (or similar) in a street driven car is also VERY unsafe. On the street, you're not wearing a helmet and if your head impacts against one of those bars, you're toast.

Yes, this is another issue with a full cage. It is not an issue with a rollbar.

This is the first REAL rollbar for an NSX. Honestly I think anyone with a harness bar should have this instead and I am thanking Ross for building one. It is not an easy build.

 

[TURBO2GO]

I think this will help visualize it.....

The bar would be a safety piece bolted to current STMPO RSTB's...

Main hoop with harness bar with rear diagnonal members.

Regards

This will also do wonders for chassis rigidity. I think Targa owners will be amazed at this.

 

[NSXGeek!]

Jim has a very good point. Running the rear members from the main roll bar to the rear shock towers will require the removal of the rear glass. It will require using a plastic rear glass that will need to be cut for holes to run the rear members through. This will make the cockpit VERY noisy, even if you apply some type of gasket between the rear member and plastic. Plastic will not attenuate the sound of the engine very well (it is not as rigid as glass and vibrations will easily pass through). Although it may look like a good idea on paper, I can assure you from personal experience that this will make the car unbearable as a street car.

 

[VBNSX]

first off I'd like to say these efforts are greatly appreciated to those who track their nsx's.... I applaud your efforts.

Just my .02 with this design
From the shock tower area to then tie into the rear firewall may not be the best option as far as how a rollbar should be designed... from what I've seen, the bar is usually independent of the car structure... what I mean is I think the bars should tie back into the structural bars somehow.

Although this also poses a problem since you do not want to have to penetrate the firewall also... I wish I could help with the solution however, I would just like to offer that since the main goal of this is based on safety.

For example my rollcage:

autopower roll bar:

v/r,
-x

 

[docjohn]

check the scca spec rules for solo 1 which mandates a roll bar..also talk to Shad at DA,he has had to design Kips car to racing regs.

 

[Ponyboy]

Love the idea. I thought of going this route, via a custom jobbie, with the same basic setup once engine work was complete. Though I'm not overly paranoid about a rollover, I would like the added safety in the event it should happen.

Not interested in going w/ a full cage by any means. The B-pillar protection is exactly what I'm looking for.

Here's what some others have done previously:

Ross, I think you're going in a great direction: providing an effective roll bar that doesn't excessively detract streetable comfort. Looking forward to the finished product!

 

[Matt_337]

If it has to be an NSX, why not this one?
http://www.nsxprime.com/forums/showthread.php?t=121252

I've been thinking of a way to swing this.

 

[CL65 Captain]

Those are all RACE CARS. My point is you have to make a decision, do you want a NSX race car or a street car? Yes, you can make a street-able race car, but be prepared for the consequences/compromises.

 

[docjohn]

I think some of us are starting to apply our own personal choices on others.Dave do whatever you want let us know how it goes.I made my decision long ago,Hrant made his,the captain made his ect....on down the line.

 

[TURBO2GO]

Jim has a very good point. Running the rear members from the main roll bar to the rear shock towers will require the removal of the rear glass. It will require using a plastic rear glass that will need to be cut for holes to run the rear members through. This will make the cockpit VERY noisy, even if you apply some type of gasket between the rear member and plastic. Plastic will not attenuate the sound of the engine very well (it is not as rigid as glass and vibrations will easily pass through). Although it may look like a good idea on paper, I can assure you from personal experience that this will make the car unbearable as a street car.

I'm pretty sure I can solve this issue. Being one of the things I have to do at my work is sound control, I know quite a bit in this area. It just requires some extra work/fabrication. I already have some ideas where the holes are totally isolated from the cabin by seperate housings. I already have bo engine cover and a very loud exhaust. I like it. Doesn't bother me at all, I don't daily drive the car. I am almost certain I can get the noise down to a totally acceptable level.

 

[Ponyboy]

I think some of us are starting to apply our own personal choices on others.Dave do whatever you want let us know how it goes.I made my decision long ago,Hrant made his,the captain made his ect....on down the line.

Thanks Doc. The perennial voice of reason.

 

[TURBO2GO]

Those are all RACE CARS. My point is you have to make a decision, do you want a NSX race car or a street car? Yes, you can make a street-able race car, but be prepared for the consequences/compromises.

Jim I would say I have already made compromises. Once you leave "stock", you are starting to already chew away from the car's "streetability". My exhaust is loud. That's a compromise. I like the sound better now. My suspension will be more harsh... it's a compromise too. My brake pads squeal some and make dust. They grip at the track, and I am fine with that. You could even say the type R has more than a few "compromises" over a standard NSX. So it is all a scale, it is not black and white street car versus "race car".

There are compromises I will NOT make. I have to limit the amount and type of driving I do on the track because it is not a race-prepped car. I realize I am at some risk on the track ALL THE TIME. I will feel a lot better having a rollbar, a harness, a hans, a suit. Anything I can do for safety and still be OK driving the same car on weekends, I will probably do. I don't believe this rollbar will take away from that.

I also believe, in a street accident, the rollbar will provide additional safety. Certainly the chassis will be much more rigid. The NSX is low, and I can see some SUV tipping sideways and laying on my roof. The targa has a fairly strong A/B pillar, but why not also have the extra protection of the rollbar above my head.

Having this and a harness I can now more comfortably remove the steering wheel/airbag and get a proper steering wheel. There are a lot of guys driving around with a momo wheel and nothing else. Am I less safe than them on the street?

I'm not racing. I am just doing DE's like many guys already do here, but I am trying to take my safety items above what everyone else seems to be doing. I don't plan on doing DE's a lot more often, doing club racing, wheel to wheel stuff, none of that. Just enough to get the feel for the car and the "itch" out of my system once in a while. The same way I play pickup basketball some weekends. Does this not make sense? If I get the itch to do more I will retire this car, get a trailer and a race prepped car like you or matt have pointed out.

 

[CL65 Captain]

Jim I would say I have already made compromises. Once you leave "stock", you are starting to already chew away from the car's "streetability". My exhaust is loud. That's a compromise. I like the sound better now. My suspension will be more harsh... it's a compromise too. My brake pads squeal some and make dust. They grip at the track, and I am fine with that. You could even say the type R has more than a few "compromises" over a standard NSX. So it is all a scale, it is not black and white street car versus "race car".

There are compromises I will NOT make. I have to limit the amount and type of driving I do on the track because it is not a race-prepped car. I realize I am at some risk on the track ALL THE TIME. I will feel a lot better having a rollbar, a harness, a hans, a suit. Anything I can do for safety and still be OK driving the same car on weekends, I will probably do. I don't believe this rollbar will take away from that.

I also believe, in a street accident, the rollbar will provide additional safety. Certainly the chassis will be much more rigid. The NSX is low, and I can see some SUV tipping sideways and laying on my roof. The targa has a fairly strong A/B pillar, but why not also have the extra protection of the rollbar above my head.

Having this and a harness I can now more comfortably remove the steering wheel/airbag and get a proper steering wheel. There are a lot of guys driving around with a momo wheel and nothing else. Am I less safe than them on the street?

I'm not out racing. I am just doing DE's like many guys on here, but I am trying to take my safety items above what everyone else seems to be doing. I don't plan on doing DE's a lot more often, doing club racing, wheel to wheel stuff, none of that. Just enough to get the feel for the car and the "itch" out of my system once in a while. The same way I play pickup basketball some weekends. Does this not make sense?

Fair enough... :wink:

I wasn't saying don't do it or it will ruin your enjoyment of the car, only take a time out and realize where you are going. The reason I say that is that after talking to a lot of people that have gone down that path only to then buy a dedicated HPDE car, that they all say they wish they had done it sooner and not been distracted by turning their street car into a pseudo track car.

But Dave, I also understand where you are coming from which is you don't want to have a tow vehicle, trailer and a $5k budget for tires. You want to drive your NSX to the track and be as safe as you possibly can within the limits of your options available.

PS: My lack of safety gear had a specific purpose.... emailing my Mom all the videos of my spins has netted me a Safety Solutions Hybrid device for my birthday next week. :tongue:

 

[TURBO2GO]

Fair enough... :wink:

I wasn't saying don't do it or it will ruin your enjoyment of the car, only take a time out and realize where you are going. The reason I say that is that after talking to a lot of people that have gone down that path only to then buy a dedicated HPDE car, that they all say they wish they had done it sooner and not been distracted by turning their street car into a pseudo track car.

But Dave, I also understand where you are coming from which is you don't want to have a tow vehicle, trailer and a $5k budget for tires. You want to drive your NSX to the track and be as safe as you possibly can within the limits of your options available. :wink:

Exactly Jim, and I do appreciate your input and the input from everyone else as well. I think where there is a will, there is a way. I am going to take this item with Ross, work on it, and make it quiet and totally streetable. Create a rigid chassis and additional safety. I totally hear you on the "mod creep" thing. Your advice is noted and in my mind.

 

[HIJACKER]

I think some of us are starting to apply our own personal choices on others.Dave do whatever you want let us know how it goes.I made my decision long ago,Hrant made his,the captain made his ect....on down the line.

I never implied a personal choice - I merely pointed out a safety consideration.

 

[StmpoRaceProducts]

It is always refreshing and encouraging to see products in their development.

I am not a structural engineer, but don't you need to have a cross bar from one of the B piller top corners to the opposite lower moutning point? Also, isn't the weakest point on the roof line the A pillar - even in a coupe per your illustration?

If this is for more than just HPDE, then perhaps looking at some specs by racing sanctioning associations might be helpful. Perhaps you have taken that into consideration already :wink:

If the drivers head were closer to the a-pillars than the b-pillars... the b-pillars would be the weakest link of the original Honda design.

If Dave called me and want a full cage... like FXMD did... we would build it for him just like we did on the FXMD car. Which.. after our cage, chassis mods, STMPO AFI Turbo set up, and Andrew Brillents Aero package... is re-breaking their old records.

check the scca spec rules for solo 1 which mandates a roll bar..also talk to Shad at DA,he has had to design Kips car to racing regs.

I like DA's car... the cage is impressive... but they arent the only shop on the block... I dont think Roger Penske calls Jack Roush to get idea's of what to do. My answer to that would be... when is DA going to call us.

We were able to incorporate a cage with substationaly less bends than DA and used composite techniques to minimize weight while increasing rigidity during the complex "how to attach aluminum a pilars to a steel cage".

I have had emails back and forth for weeks with Dave... followed by a few phone calls well over an hour. Dave is getting exactly what he wants from a company that has the resources to explain and help him understand what can and cant be done for what he is trying to do...

Here is the pic showing how cages MUST hit frame rails to actualy work

Pic showing the gas lever as a reference point... Then telling Dave to go look at how his door panel sits directly above it so this application is not doable... also

reminding him the glass hatch latch needs to remain functional as well...

This pic shows the distance from the bolt location of the seat mount in reference to the passenger frame rail... "how much do we have to work with"

Then showing how much the carpet changes that

But showing how we can still get the chromoly to clear with a side mount steel frame rail plate.

I think some of us are starting to apply our own personal choices on others.Dave do whatever you want let us know how it goes.I made my decision long ago,Hrant made his,the captain made his ect....on down the line.

That should be an NSX Prime Signature!

Regards

 

[StmpoRaceProducts]

It is always refreshing and encouraging to see products in their development.

I am not a structural engineer, but don't you need to have a cross bar from one of the B piller top corners to the opposite lower moutning point? Also, isn't the weakest point on the roof line the A pillar - even in a coupe per your illustration?

If this is for more than just HPDE, then perhaps looking at some specs by racing sanctioning associations might be helpful. Perhaps you have taken that into consideration already :wink:

I can explain the requirements as well as all differences between FIA, SCCA (many classes), and NASA cage requirements off the top of my head...

Which Dave has not only heard over the phone.. I provided him the links to research on his own.

Regards