Rollbar / seats / harness stuff, yet again...

wstar · 02-12-2012, 07:11 PM

I know, this topic is a source of endless noob questions. Here comes another:

So my current situation is stock belts, no roll-bar/cage at all, and a set of reclinable pseudo-racing seats with a composite shell. The car is still used at least partially on the street, and will be for a while (even if I pick up another DD soon, I won't likely be picking up a truck and trailer, so still a lot of highway miles to tracks, etc).

I'm aware that all things considered, there's actually only a very narrow set of safe upgrades you can do that are anywhere in-between "fully stock" and "fully caged race car" when it comes to cage/bar/seats/harness stuff, which cuts out a lot of options right off the bat.

Over the past week or two I had pretty much settled on my next upgrade being a a custom-welded 4-point cage in the rear (high/back enough that my head can't smack it, and of the right dimensions that I could add a forward portion later and meet current SCCA/NASA rules), combined with Scroth 4-point harnesses with their ASM system to prevent submarining (since my reclinables don't have seat floor holes for 5/6/7-point anti-sub straps). This is of course leaving the front airbags working, and leaving the stock belts in for street use.

This seems like it avoids all the big obvious street+track config safety problems. It would be more-ideal if my seats had anti-sub holes and I could install a 6-point, but I think the Scroth ASM thing seems like a pretty decent solution to that problem for now.

I've seen some references to the idea of using a 6-point harness without seat-floor holes (and without the stupid move of going over the front of the seat), by basically routing them under your *** and out the same exit as the lap belts, apparently used in some formula cars. The concept and mounting angles and effectiveness of that setup are a little unclear to me though.

My bigger concern is this: is it safe to put a 4-point cage behind a reclinable, composite seat? It seems like even good-quality ones are subject to hinge failure in serious accidents (esp if rear-ended). If it lays over into the floor in the rear that's a relatively livable outcome. But with the cage bars immediately behind it (and we are talking like 6-8 inches tops), would it smack into them with enough force to crack the composite shell, and subsequently my spine?

I should add: it's pretty much a given that if I upgrade to a full cage down the road, I'd also swap in solid aluminum seats with a bolted or welded seat-back brace to the cage, but I don't think such seats are appropriate at this stage

M.Bonanni · 02-12-2012, 07:33 PM

Well first off, I think you would be surprised at how much you actually move around in the event of a roll over or big impact. Second if your cage was truly far enough back that you couldn't hit your head on it, then its too far back to protect you in a roll over anyway. No matter which way you argue it, this debate is very black & white. There are no gray areas, safety will have to be compromised one way or another.

wstar · 02-12-2012, 09:50 PM

So your recommendation is (ignoring the reclining seat thing for a moment), "don't put even a 4-point in a car you'd ever drive without a helmet"?

As for rollbar placement, well there's really only two possible spots for the main hoop on the 370. They're definitely close enough for rollover protection. I wouldn't think my head could go both up + back that far, but I'll take your word on it that wreck movement can be more than expected

cossie1600 · 02-12-2012, 10:20 PM

Quote:

Originally Posted by M.Bonanni

Well first off, I think you would be surprised at how much you actually move around in the event of a roll over or big impact. Second if your cage was truly far enough back that you couldn't hit your head on it, then its too far back to protect you in a roll over anyway. No matter which way you argue it, this debate is very black & white. There are no gray areas, safety will have to be compromised one way or another.

I second that. I have seen two guys lost their lives over little accidents on the street thanks to the bar on the street even though they have the racing seat and harness. They were all fairly minor impacts too. Btw, aren't the side airbags from the seats?

wstar · 02-12-2012, 10:28 PM

I wouldn't run a harness on the street regardless, it's too restrictive for turning your head, etc. These two stories you're talking about were un-helmeted heads hitting 4-pt rollbars?

And yes, the side airbags are in the stock seats, whereas the curtain ones come from the roof. No doubt everything is tradeoff, I'm just trying to find a reasonable tradeoff. I'm a pretty safe driver on the street, I think, but I can't predict what other idiots will do nearby me with infinite precision

I guess I should preface all of this with those sorts of blanket statements about how most people survived ok before the advent of X, and all modern safety features as for corner cases, it's all a percentage game, blah blah. I get all of that, hence finding a reasonable tradeoff. I just don't want to do something in the name of increased *track* safety that seems like a really stupid (and life-altering) decision due to an unpredictable street collision, in hindsight, because it made the situation far worse.

wstar · 02-13-2012, 07:10 AM

Perhaps a better way to word my immediate concern: would it be a significantly better idea if I held off on a 4-point rollbar until I can get some fixed-back seats in there at the same time?

cossie1600 · 02-13-2012, 09:09 AM

Personally I would skip it all together until you are ready to get a decent cage or decide to not drive the car daily again

M.Bonanni · 02-13-2012, 09:43 AM

Seats aren't as much of a concern to me as head impact. So I would say hold off on a roll bar until you're ready to wear a helmet every time you're in the car. No shame in rocking a helmet/hans on the highway haha.

wstar · 02-13-2012, 11:11 AM

I guess I could add that a "daily" driver for me isn't daily to begin with. I have no commute or traffic, I work from home and occasionally take it down the road to pick up fast food or car parts or whatever. But yeah I guess I'm just grasping for excuses at this point.

Mostly, the whole drive behind this is that even with the high-bolster seats I have now, I don't like my torso swaying around while I'm trying to steer through things (and shifting forward under braking, too). It's just a world of difference compared to being strapped into harnesses in the passenger side of an instructor's car. And then logically following: can't have harnesses without semi-proper seats and a 4-point cage at least.

wstar · 02-13-2012, 11:13 AM

Quote:

Originally Posted by M.Bonanni

No shame in rocking a helmet/hans on the highway haha.

Hah! Is that even legal, for driving to/from events?

cossie1600 · 02-13-2012, 01:09 PM

Aren't most track side injuries related to side impact more than rollovers?

wstar · 02-13-2012, 01:56 PM

Quote:

Originally Posted by cossie1600

Aren't most track side injuries related to side impact more than rollovers?

No idea here. As I said above, the point of contemplating the 4-point was less about rollover worry than about safely mounting harnesses for better driving, without upgrading a rare rollover event into a suicidal event.

I really don't expect my car to roll over at an HPDE at all, it seems far more likely that I get an angled hit on a (hopefully tire) wall, get rear-ended coming down into a corner by some guy with a brake problem, or something of that nature. I suppose a side-hit would be likely if I spun out and came back across the track into someone's path.

Probably bad luck to even mention it, but I've never had real, complete spin in this car. My closest call was on my very first time at a road course ever (direct link to a few seconds before: MSR Aug11). That was technically a spin in the sense of "off-track excursion", but meh that's semantics. I've never lost control to the point that the car went back-end-first or even fully sideways towards anything, and I really don't plan on it. You know how plans go, though

wstar · 02-14-2012, 11:41 AM

In any case, thanks for the feedback you two, it's really helped to put this all in perspective. I've been pushing myself and my car to get more serious, but there's a big gap in front of me between where I'm at now, and where I'd like to be, and I really need to step back from this and cross the gap rationally. I've been trying to find a way to make the care more-race-able without giving it up as a street car for now, but it's just not possible in this direction (4 point).

I'll keep going with the other minor upgrades for now. I've been trying to limit my further upgrades to happening in response to actually feeling out limitations, which is why I held off on coilover upgrades for so long: it wasn't until my most recent event that I actually felt limited by the stock ones (the car was poirposing too much in some short braking zones, probably contributed to ice-mode come to think of it).

I'm at a point now where I feel the need for harnesses on the track, but I think I have to live with that limitation for now, until the car becomes more-dedicated to the purpose at hand (which in turn means I pretty much have to budget out a new DD first, and then get back on the car-building process).

Either that or completely reverse course, undo a bit of the more aggressive Z mods, keep it as a DD, and buy some cheaper caged car for track use (e.g. all the SpecZ thread action going on around here). I'd hate to have to give up my cheater paddle shifters though!

M.Bonanni · 02-14-2012, 11:54 AM

Try a CG-Lock for now. It at least keeps your lap belt tight, and its only $60. Can be used on any car with 3-point belts too. I still use the one I bought 6 years ago.

Car Booster Seat Safety - CG-Lock.com

wstar · 02-14-2012, 11:57 AM

Quote:

Originally Posted by M.Bonanni

Try a CG-Lock for now. It at least keeps your lap belt tight, and its only $60. Can be used on any car with 3-point belts too. I still use the one I bought 6 years ago.

Car Booster Seat Safety - CG-Lock.com

Hah, you read my mind, I just ordered one through Amazon about 10 minutes before I posted above

I'm a little bit dubious of it, but I'm sure it'll be better than nothing.

02-12-2012, 07:11 PM	#1 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3594	Rollbar / seats / harness stuff, yet again... I know, this topic is a source of endless noob questions. Here comes another: So my current situation is stock belts, no roll-bar/cage at all, and a set of reclinable pseudo-racing seats with a composite shell. The car is still used at least partially on the street, and will be for a while (even if I pick up another DD soon, I won't likely be picking up a truck and trailer, so still a lot of highway miles to tracks, etc). I'm aware that all things considered, there's actually only a very narrow set of safe upgrades you can do that are anywhere in-between "fully stock" and "fully caged race car" when it comes to cage/bar/seats/harness stuff, which cuts out a lot of options right off the bat. Over the past week or two I had pretty much settled on my next upgrade being a a custom-welded 4-point cage in the rear (high/back enough that my head can't smack it, and of the right dimensions that I could add a forward portion later and meet current SCCA/NASA rules), combined with Scroth 4-point harnesses with their ASM system to prevent submarining (since my reclinables don't have seat floor holes for 5/6/7-point anti-sub straps). This is of course leaving the front airbags working, and leaving the stock belts in for street use. This seems like it avoids all the big obvious street+track config safety problems. It would be more-ideal if my seats had anti-sub holes and I could install a 6-point, but I think the Scroth ASM thing seems like a pretty decent solution to that problem for now. I've seen some references to the idea of using a 6-point harness without seat-floor holes (and without the stupid move of going over the front of the seat), by basically routing them under your *** and out the same exit as the lap belts, apparently used in some formula cars. The concept and mounting angles and effectiveness of that setup are a little unclear to me though. My bigger concern is this: is it safe to put a 4-point cage behind a reclinable, composite seat? It seems like even good-quality ones are subject to hinge failure in serious accidents (esp if rear-ended). If it lays over into the floor in the rear that's a relatively livable outcome. But with the cage bars immediately behind it (and we are talking like 6-8 inches tops), would it smack into them with enough force to crack the composite shell, and subsequently my spine? I should add: it's pretty much a given that if I upgrade to a full cage down the road, I'd also swap in solid aluminum seats with a bolted or welded seat-back brace to the cage, but I don't think such seats are appropriate at this stage __________________ 7AT Track Car! Journal thread / Car setup details Last edited by wstar; 02-12-2012 at 07:19 PM.

02-12-2012, 07:33 PM	#2 (permalink)
M.Bonanni The370Z.com Sponsor Join Date: Nov 2008 Location: Las Vegas Posts: 2,575 Drives: Fast Rep Power: 1321	Well first off, I think you would be surprised at how much you actually move around in the event of a roll over or big impact. Second if your cage was truly far enough back that you couldn't hit your head on it, then its too far back to protect you in a roll over anyway. No matter which way you argue it, this debate is very black & white. There are no gray areas, safety will have to be compromised one way or another. __________________ MikeBonanni.com Twitter: http://www.twitter.com/MikeBonanni Facebook: http://www.facebook.com/MBonanni36 Function > Form

02-12-2012, 09:50 PM	#3 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3594	So your recommendation is (ignoring the reclining seat thing for a moment), "don't put even a 4-point in a car you'd ever drive without a helmet"? As for rollbar placement, well there's really only two possible spots for the main hoop on the 370. They're definitely close enough for rollover protection. I wouldn't think my head could go both up + back that far, but I'll take your word on it that wreck movement can be more than expected __________________ 7AT Track Car! Journal thread / Car setup details Last edited by wstar; 02-12-2012 at 09:52 PM.

02-12-2012, 10:28 PM	#5 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3594	I wouldn't run a harness on the street regardless, it's too restrictive for turning your head, etc. These two stories you're talking about were un-helmeted heads hitting 4-pt rollbars? And yes, the side airbags are in the stock seats, whereas the curtain ones come from the roof. No doubt everything is tradeoff, I'm just trying to find a reasonable tradeoff. I'm a pretty safe driver on the street, I think, but I can't predict what other idiots will do nearby me with infinite precision I guess I should preface all of this with those sorts of blanket statements about how most people survived ok before the advent of X, and all modern safety features as for corner cases, it's all a percentage game, blah blah. I get all of that, hence finding a reasonable tradeoff. I just don't want to do something in the name of increased track safety that seems like a really stupid (and life-altering) decision due to an unpredictable street collision, in hindsight, because it made the situation far worse. __________________ 7AT Track Car! Journal thread / Car setup details Last edited by wstar; 02-12-2012 at 10:33 PM.

02-13-2012, 07:10 AM	#6 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3594	Perhaps a better way to word my immediate concern: would it be a significantly better idea if I held off on a 4-point rollbar until I can get some fixed-back seats in there at the same time? __________________ 7AT Track Car! Journal thread / Car setup details

02-13-2012, 09:09 AM	#7 (permalink)
cossie1600 A True Z Fanatic Join Date: Jun 2009 Location: californee way Posts: 5,380 Drives: 370, Leaf Rep Power: 30	Personally I would skip it all together until you are ready to get a decent cage or decide to not drive the car daily again

02-13-2012, 09:43 AM	#8 (permalink)
M.Bonanni The370Z.com Sponsor Join Date: Nov 2008 Location: Las Vegas Posts: 2,575 Drives: Fast Rep Power: 1321	Seats aren't as much of a concern to me as head impact. So I would say hold off on a roll bar until you're ready to wear a helmet every time you're in the car. No shame in rocking a helmet/hans on the highway haha. __________________ MikeBonanni.com Twitter: http://www.twitter.com/MikeBonanni Facebook: http://www.facebook.com/MBonanni36 Function > Form

02-13-2012, 11:11 AM	#9 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3594	I guess I could add that a "daily" driver for me isn't daily to begin with. I have no commute or traffic, I work from home and occasionally take it down the road to pick up fast food or car parts or whatever. But yeah I guess I'm just grasping for excuses at this point. Mostly, the whole drive behind this is that even with the high-bolster seats I have now, I don't like my torso swaying around while I'm trying to steer through things (and shifting forward under braking, too). It's just a world of difference compared to being strapped into harnesses in the passenger side of an instructor's car. And then logically following: can't have harnesses without semi-proper seats and a 4-point cage at least. __________________ 7AT Track Car! Journal thread / Car setup details Last edited by wstar; 02-13-2012 at 11:14 AM.

02-13-2012, 01:09 PM	#11 (permalink)
cossie1600 A True Z Fanatic Join Date: Jun 2009 Location: californee way Posts: 5,380 Drives: 370, Leaf Rep Power: 30	Aren't most track side injuries related to side impact more than rollovers?

02-14-2012, 11:41 AM	#13 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3594	In any case, thanks for the feedback you two, it's really helped to put this all in perspective. I've been pushing myself and my car to get more serious, but there's a big gap in front of me between where I'm at now, and where I'd like to be, and I really need to step back from this and cross the gap rationally. I've been trying to find a way to make the care more-race-able without giving it up as a street car for now, but it's just not possible in this direction (4 point). I'll keep going with the other minor upgrades for now. I've been trying to limit my further upgrades to happening in response to actually feeling out limitations, which is why I held off on coilover upgrades for so long: it wasn't until my most recent event that I actually felt limited by the stock ones (the car was poirposing too much in some short braking zones, probably contributed to ice-mode come to think of it). I'm at a point now where I feel the need for harnesses on the track, but I think I have to live with that limitation for now, until the car becomes more-dedicated to the purpose at hand (which in turn means I pretty much have to budget out a new DD first, and then get back on the car-building process). Either that or completely reverse course, undo a bit of the more aggressive Z mods, keep it as a DD, and buy some cheaper caged car for track use (e.g. all the SpecZ thread action going on around here). I'd hate to have to give up my cheater paddle shifters though! __________________ 7AT Track Car! Journal thread / Car setup details

02-14-2012, 11:54 AM	#14 (permalink)
M.Bonanni The370Z.com Sponsor Join Date: Nov 2008 Location: Las Vegas Posts: 2,575 Drives: Fast Rep Power: 1321	Try a CG-Lock for now. It at least keeps your lap belt tight, and its only $60. Can be used on any car with 3-point belts too. I still use the one I bought 6 years ago. Car Booster Seat Safety - CG-Lock.com __________________ MikeBonanni.com Twitter: http://www.twitter.com/MikeBonanni Facebook: http://www.facebook.com/MBonanni36 Function > Form

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