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Mugen Rollbar

Now, my own reply to the thread:

While I think this is a very necessary part for NSX's that are tracked, use R type or aftermarket seats, harnesses, or ones that have removed their airbags, some serious questions remain about the actual strength and functionality of this bar. We have discussed this before, and many think it is an expensive show-piece and nothing else. It certainly will not pass any inspection at any serious track. It does not connect to the rear strut towers, nor, like the comptech bar, does it connect to the front frames of the car. It basically is not a "V" but an "i".

I do not want to be harsh on this bar. There are many items that are laughed at by cage builders, but some of them do probably increase protection. Will this help in a rollover? maybe....

will it come loose and become a dangerous object in the cabin in an accident? Maybe... we don't know for sure.

I can tell you that at best it does not do what it claims. It is not a true "rollbar". But I knew for sure that it did in fact increase protection and was better to have in MOST scenarios, I would be the first to sign up. STMPO was going to build a real rolbar for the NSX but it never materialized. This is probably the best we have now, short of the Comptech bar which is big, heavy, and no longer made. That I believe was a steel bar, not chromoly.
This is the Comptech bar. As you can see, it connects up front.


It may be possibe if one is going to replicate the mugen to actually improve its design. Its lower connection points are not good, but a small redesign that attaches it to the frame rails may be a huge improvement.

STMPO rollbar and related thread:


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Don't get me wrong, looks like a great add on piece for show cars.... But for daily driving I agree with ryu, it's a death trap.
I'm all about chassis stiffening and safety but on most cars, driving around with a cage and NO helmet makes for a death trap.

It's a rollbar not a cage. Technically... behind you.. in most states legal on a road car.

I'll say this, on the NSX the biggest issue is the closeness of the cabin to your head. I have perhaps an inch before my head will smash into the B pillar... a few inches to the side glass. A 3 point belt does NOTHING as you are violently thrown up and down, moving vertically and not fore and aft. If you watch most crash test, injury occurs upon contact with the cabin, which is almost assured in an NSX. A harness keeps you belted down and keeps you from bouncing up and down and a lot less side to side.

When you talk about an accident or a crash, everyone assumes a forward crash... and so they say "oh leave it alone and do the airbag and 3 point". The more research I do into safety, the less I like 3 point belts. The reality is that multiple airbags now try to do what the belt isn't doing. Controlling your body. Harnesses are often rejected as a safety item because of the fear of spinal injury if the roof caves in... something that gets played out over and over on car forums without people actually having done any research about it.

I'd feel safer with a harness, a lower seat, and some sort of rollbar. I think you'd increase your safety by a HUGE margin.
From a price point... Wouldn't a cage cost just as much or a little more. I've gotten a cage done before and costs in the realm of about 4k. The only bad thing is thats it's more permanent.
I just sent pics of my bar to a guy that will post it on the parts for sale post cuz I dont know how to lol. should be up by tomorrow. If you get a chance please grab those pics and replace instead of the ones that are up here. The photos shown here are of a mugen bar but its polished, which in my opinion is showy. They did not come polished originally. Im not claiming to know about rollover protection im just trying to help out the guys who are interested in this bar. I should have been clear: if you are tracking your car then this is not near the protection of a full cage, that would be the route you want to go for sure. For the other inquiry- Chromoly is 33% lighter and stronger than steel. thx guys. pm me if your interested, im compiling a list.
I don't think you'll get too many guys that will shell out $2500 for something that just looks cool and could possibly be dangerous. But I do think if the bar was made slightly different you may have a long list of buyers and those are people currently running harness bars and people who track their cars. I guess what you're saying is you don't really care about those guys? Those are probably the majority of guys interested in such a thing and would spend north of 2K. At that point it would be for something functional.

Also your post is just in the wrong section and is going to be deleted along with your photos. That's parts for sale, not inquiries or group buys on a part to be made. This is the section you want to post in which is why I posted here. I was trying to help you out. If you post photos it should be here, not there.
Oh I totally dont want to sell or do anything dangerous at all thats not my intention and Im sorry if I offended anyone. I do appreciate your help. Basically the bar is what it is: I have given all the information I know and it looks like we have some professionals on here that can further the knowledge thankfully. I have had inquiries to purchase it and thought it would be a good idea to fab some up rather than saying nobody can have one I'd rather be the kind of person that says yes lets make this happen. I guess its up to the buyer to research the application and what they want to use it for and of course how much they want to pay.
Anyways that being said I appreciate your tips about where to post stuff. When I read the "rules" about vendors, it says I have to be set up as a vendor etc etc before posting. I was just putting the feelers out there to see if there was any interest at this point. Thanks eveyone for your helpful information. I have owned an nsx for all of one month so I'm new to this world and looking forward to learning lots. Cheers.
Kevin its very nice of you to do this, and perhaps some people will want a replica anyway. Guys do all sorts of dubious things for looks and give up safety and some are probably a lot worse than not knowing what a rollbar does or doesn't do. Most however are just unaware of the safety compromises that they are making. I am sure you were not aware of the possible dangers of that bar. There is more than one guy here with a bolt-in "no cut" rollcage, that seems quite ill-designed and dangerous to me. The whole issue is if these come loose now you have a big metal object floating around the cabin with you.

I do think also that because of a lack of knowledge about many things NSX, owners assume that OEM is best and that any number of things were designed with a whole lot more thought than they actually were. It's normal and I was one of those guys. They think because something is a type-R, as far as suspension or aerodynamics that it will just surpass anything non-OEM but that's just not true. The minute you ask someone with true knowledge whose profession is that area, they look at the OEM and say "no, that's not all that great". For the longest time it was assumed that the factory spare tire was part of a frontal crash system and that its removal was quite dangerous until someone here was able to speak with one of the engineers that designed the NSX and he put that to bed once and for all.

I would rate this car's safety as marginal to moderate by today's standards. There just was not enough technology back then like there is today. On targa cars especially, I think a rollbar may be a tremendous assett not just for the track but also in a bad street accident. Did Mugen, the highly prized God of aftermarket NSX parts design something dangerous? I will tell you for sure that is quite possible. The question in any safety system isn't whether it is perfect or not, but more of do the benefits outweigh the drawbacks. Even an airbag can injur or even kill you within the right scenario and no two accidents are the same.

IMO you would need to have someone professional, probably more than one person, take a look at the car and that bar and get their opinion. And the question they should answer is simply does it increase safety OVERALL, and not will it pass safety regulations at various tracks and clubs for racing. The second answer will most likely come back as a no, but many like myself would welcome a unit that adds a level of safety especially with a harness.

Please look through my thread and look at the connection points that Ross at STMPO pointed out such a bar should have. It is not at the seat mounting points, but to their sides where the frame rails are. This is an easy mod for such a bar and would make it much more effective. Ross would be a great source of info here but as usual he is banned again because of comments he made regarding SOS on my wheel group buy thread.

Do you have anyone local that makes cages and bars locally you can show this thing to? You would be making a unique product that would sell for years to come and really doing the community a tremendous favor. I'll help you all I can, I don't want you to be discouraged in any way.
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I have the Comptech roll bar.
I thought I heard Shad still has one and may also make them if there is interest?

I have never seen another car with one. To everyone's surprise I leave the side bars in. This is my track car but also a daily driver.

What happened to the first post and the pictures???

Don how far does it limit your ability to slide the seat back? How much did you lose?

The Comptech bar works. It also provides some side impact protection with the side bar. It's definitely not near your head, I can see it being streetable, although not comfortable. Did you pad yours at all? The CT bar is quite thick and heavy. Id like to see one made of chromoly.
What are your thoughts on this: In addition to offering the exact mugen replica (I have had overwhelming interest already, which is good it will drop the price point). It is perfect for daily driven or street cars because of its ease of installation, and clean look. Like you said coupled with a harness its will add some level of protection and looks great. Not reccomended for track.

I will also offer the modified version of it using the frame connection points like you suggested, or perhaps four points similar to the comptech bar depending on what you track guys would prefer.Will also have to raise up the arched part bring closer to roof and forward to clear or add a crossbar that connects the two arches and contours higher to the roof. This design will look great, be light and strong as heck. Were talking about two completely different products here, of course. I will be talking with some local reputable builders this week and let you know what I come up with. Thanks again
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Well, it might either add some level of protection or it might kill you, depending on the type of accident. You need to be very careful with such a product and perhaps have a lawyer write something up that frees you from liability on this. For off road use only. The last thing you want is someone buys this, does something stupid and gets killed 3 years down the road, and you as the vendor get a phone call from the family's lawyer. It's a litigation happy world. You're not selling shift knobs.

I'm really alarmed at the number of guys on this forum that seem to care so little about their safety. They remove airbags, put in seats that aren't supposed to be used with 3 point belts, bolt in rollbars and "cages", run harnesses improperly, and don't seem to really want to engage in conversations I bring up about safety.

I would love to see what a cage builder has to say about this bar. If you develop a more functional version I'll be your first customer. As I've repeatedly said, I am not a fan of 3 point belts. They are a compromise designed for convenience. 9 airbags and two pretensioners work hard to make something functional out of a shitty design.
It's also possible that a real professional looks at it and the cars B and A pillars and says "it's fine. This adds safety". You'd have to find someone with some serious credentials. But if someone like that approves it, you might sell quite a few. Too many NSX's run on the track now with nothing more than a harness bar.
Good points. I plan on research and developing this project properly and covering all of my bases. I am a successful business owner already (not car related) but the same concepts apply - "do s**t right". I am going to be a member of the nsx community for a very long time and want to build a good reputation from the get go.
Well the first thing is you didn't take any offense to anything I said which is always the sign of a good business person.
What happened to the first post and the pictures???

Don how far does it limit your ability to slide the seat back? How much did you lose?

The Comptech bar works. It also provides some side impact protection with the side bar. It's definitely not near your head, I can see it being streetable, although not comfortable. Did you pad yours at all? The CT bar is quite thick and heavy. Id like to see one made of chromoly.

With the stock seats I don't recall travel being limited. Stock seats will rub the bar but can go pretty far forward. Back is not an issue at all.
Aftermarket side bolsters are wider than the stock seats and will be a issue moving the seat forward.

I added padding to the roll bar above my head. and to the right.
I have a removable pad for the side bars that I use on the track.

Most would not consider this streetable. You need to clime over the bar getting in and out. I have gotten use to it. Once in the bars don't bother me. You can always remove the side bars for street use, I don't.
Forward?? I don't quite get this.

The side bar is on a down ward angle going forward.
When the seats are all the way back it is under the bar.
As you move the seats forward the side bolster hits the underside of the side bar.
You can not move the seat very far forward.

Luckily I have long legs. :smile:

I have Recaro Profi small seats and the side bolsters hit the side bar.

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What happened to the first post and the pictures???

Don how far does it limit your ability to slide the seat back? How much did you lose?

The Comptech bar works. It also provides some side impact protection with the side bar. It's definitely not near your head, I can see it being streetable, although not comfortable. Did you pad yours at all? The CT bar is quite thick and heavy. Id like to see one made of chromoly.
I dont know how i got to be the first post here as its not my thread, however i am keen to look at any part that may be functional here and looks the part (if there is such a thing).
I have looked at the STMPO solution and agree with what Ross has said i just dont want to go through my rear glass i still street the car more than track.
Which may mean I've answered my own question and these things are a waste of time and could possibly be dangerous, however if it is possible to knock one of these out or combine what Comptech have done then i want to see it and take it from there.
Most of us at the odd time would like to take someone for a spin around the track, more and more tracks will not let you do that if you dont have a cage or an approved roll bar, it may not be possible to have either, as far as I'm concerned i do not want a cage.
Its also the first time i have seen a photo of the comptech bar how hard is it to take out the side bar so when your not at the track you can be a bit more normal getting in and out?
Chromemoly is what all dirt bikes are made out of unless they have gone to a twin spar aluminium frame which means its tuff and light and has flex which is important in these applications.