Stock Seat with 5 point harness

[titaniumdave]

Re: 5 pt vs 6 pt.

Para 6. The double leg straps of the 6 pt or 7 pt system may be attached to the floor as above for the 5 pt system or be attached to the seat belt so that the driver sits on them, passing them up between his legs and attaching either to the single release common ......."

Every formula car driver I know or see sits on the sub straps. Just my observation.

Very interesting, thanks for the new information! Since this conversation has been about stock seats, I wonder if this holds true there as well. With a competition seat, the waist belt holds you down and back, with my harness bar on my stock seats, the waist belt seems to only hold me back. My fear with the 6 point going under my butt is I could rise up in an accident, guess that would be counteracted by the shoulder straps. It just seemed like a better idea to be held into the seat with straps, instead of the straps holding me against the straps...

All said, interesting conversation:wink:

 

[Larry Bastanza]

Dave,

That was exactly my thinking about the 5 point too. The other point is that the shoulder straps in the Scroth review shows the harness bar specifically being lower then the drivers shoulders. My harness bar really is not(I have the Dali), so it still leaves me thinking that if the shouder straps are not lower then you can actually move upward in a rollover.

As typical documentation about safety, it relates specifically to the entire "system" shown. So I personally have not thrown out the 5 point setup as "bad" in my specific setup. Since the shoulder belts are essentially horizontal for me (5'4") I do think I can move upward. To solve that I would need to lower my harness bar behind the seat.

Now that does open paddora's box about many of the NSX harness bar setups

Agreed this is a very worthwhile conversation.

Regards,
LarryB

 

[Hrant]

Larry, where have you mounted your lap belts and the sub belt(s) on the Dali harness bar? According to post 16 picture, the Comptech bar's shoulder mount is lower than the top of the seat which means it will be pulling down on the seat up to where comes over the seat. Perhaps that would be the solution for you?

Dave, what type of harness bar are you using and again where have you mounted the lap belts?

I offered a picture in my post 47 of a "possible" solution for the lap and sub belts. Not sure if it is workable or not. Alternatively, what about mounting the subs on the lower cross bar of Comptech harness bar and just leave the mounting position of the lap belts where they are. Still not the 20 degree angle that we are seeking but getting closer perhaps?

 

[Larry Bastanza]

Hi Hrant,

OK, now you made me uncover my car to investigate. There is 12" of snow outside and still falling steadily out here. My Dali bar is just slightly below the line intersecting the top of the seat and the headrest, which is where the harness shoulder strap sits. Now since I am 5'4" I have the seat about 2/3 of the way forward. In that position the should strap is so close to horizontal it might as well be IMO. Now if you are taller, you would certainly have the seat back more, but also possibly more upright.

My lap belts are mounted to the seat with the original OEM belt. I do not have a sub at this point, I did not track the car this year, but will go back and I have been told as I have gotten faster the sub belt should be in, that is why this topic is so interesting to me, I need to make a choice.

Thanks,
LarryB

 

[titaniumdave]

Dave, what type of harness bar are you using and again where have you mounted the lap belts?

Hrant,
I have a Dali harness bar with the lap belts mounted to the harness bar at the points above the rear seat rail mounts. For me, I have to say this set up does not feel safe with out the 5th point strap. I have a Dali lower cushion for extra helmet clearance and this may drop my pelvis low enough the lap belt does not stay on my pelvis with out the 5th point strap.

Dave

 

[Hrant]

Thanks Dave. So to recap, we have the following variables that need to be addressed in combination for proper set up.

1. Whether the sitting position is lowered or not (OEM seat with Dali cushion or no cushion or aftermarket seats). The shorter a person, the more serious this issue becomes with the angle of the mounting points.

If the sitting position is lowered, then I am concluding that the current options are not ideal for the lap belt mounting on the Comptech or the Dali bar. We still don't have any input from SoS.

2. Given scenario (1) above, it is best to have either a 5 point or 6 point harness belt to keep the lap belt from moving up. While intuitively the 5 point seems to offer a more "visual" assurance, the 6 point is preferred albeit the mounting location at issue.

3. Between the lap belt or the sub belt mounting points, I am thinking that given the available harness bars, the mounting of the sub belt is more important for those who need extra room to clear their helmet without roll bars.

I think for the 5 point, Dave's solution is a good one - especially if lap belt is not too far off from 20 degrees. Dave and Larry, do you have pics regarding the mounting point of the lap belts. I am trying to visualize the hardware used to meet the specs.

For the 6 point, please see the suggestion pictured in post #47 above or mounting the sub belt on the lower cross bar of the Comptech harness bar - that way it will be lower and not doing an L inversion before it goes between the cushions. Still unless the seat is almost all the way to the back, this would barely meet the 20 degree angle recommended mounting. Not sure if the lap belt is workable in that picture.


EDIT: I just talked to Shad at Comptech and I am now comfortable with the following solution/resolution.

(a) Keep the lap belt seat mount where it is on their harness bar - using their bolt mount. There is little difference in moving it down to the rail mounting bolt. Given the configuration of the OEM seat and my body physique/size (5'11'' hovering around 195/200lbs), the lap belt has no other angle than to go by the corner of the seats - where the OEM seat belts go by as well.

(b) Mount the sub belts on the lower cross bar just like you would the shoulder belts, and pass the belts through the seat the way Ted did. The key in keeping the lap belts from from inching up is to make sure the sub belts are tight. This mounting location is the same set up on Kip's car as well because Kip's racing seats have openings as well - but his goes under the seat. [Comptech offered the bolt mounting solution for sub belt for those who had no other option.]

YMMV.

 

[Hrant]

Here is what the final solution looks.

Note that the seat without cushion is literally sitting on the floor. I taped the wires so they won't move. The foam cushion is 1/4" thick; its enough to keep you in relative comfort - I am sure there are better options for that but it will be at the expense of helmet room. When not in track mode, just put the seat cushion over the sub belt and it will hide it; or you can pull it out and store behind the seat like the passenger side.

I still think each of the sub looped mountings needs a clip to secure it from sliding towards each other.

I left the passenger seat cushion as is. Just slide the sub belt whenever you go to the track. HTH. YMMV.

 

[HIJACKER]

Bumping this thread. Even though the thread originally started around a 5-point harness discussion, the majority of the information of photos are all of the 6-point.

On that note, can someone clearly tell me the best mounting locations for all 5 points on a Simpson 5-point harness? The two shoulder ones are the easiest, going up by the headrest and looping around the harness bar. I'm looking for more clarification on the two lower belts and the 5th?

Thanks.

 

[SFNSXguy]

FYI my 6-pt belt (Schroth) setup is nearly identical to Hyrant -- my sub is identical location but goes to a custom seat-belt mount I had Dali make many years ago... my shoulder belts go to a RM Racing shoulder belt bar (no longer made) that is located a bit better than the Comptech/Dali bar. My install meant NO new holes drilled.
My install also allows the driver's seat to go back ALL THE WAY without the seat back touching anything. I'm 6'3" and use a Dali bottom cushion when I wear a helmet.
The sit-on-them sub belts are the way to go -- I've used them for decades in sports-racers.

 

[docjohn]

Bumping this thread. Even though the thread originally started around a 5-point harness discussion, the majority of the information of photos are all of the 6-point.

On that note, can someone clearly tell me the best mounting locations for all 5 points on a Simpson 5-point harness? The two shoulder ones are the easiest, going up by the headrest and looping around the harness bar. I'm looking for more clarification on the two lower belts and the 5th?

Thanks.

comptech designed a bracket for the lap belts that is secured by the seat rail screw and is angled to allow the belt to lay across the waist.

 

[Osiris_x11]

ideas from afar...

Bumping this thread. Even though the thread originally started around a 5-point harness discussion, the majority of the information of photos are all of the 6-point.

On that note, can someone clearly tell me the best mounting locations for all 5 points on a Simpson 5-point harness? The two shoulder ones are the easiest, going up by the headrest and looping around the harness bar. I'm looking for more clarification on the two lower belts and the 5th?

Thanks.

Here's my input...

Anti-sub belts:

- driver's side: purchase (1) Simpson (red) dual anti-sub camlock-harness belt (shop-around, get used/etc), install it on the driver's side (thru the seat upper-cushion, fastened to the harness-bar lower inner bolt holes [lower outer bolt holes used for lap-belts]). This means no seat-cushion cutting, no drilling in the floor-board & attaching a mounting-plate. And now a 6-point race harness.

- passenger's side: combine the existing two Simpson (red) single anti-sub camlock harness belts (thread them thru the camlock-harness bracket), purchase (2) Simpson bolt-in mounting brackets or (2) Simpson spring-loaded mounting brackets clips (for each end of the anti-sub camlock harness belts), fastened to the harness-bar lower inner bolt holes using either i-bolts or bolts/washers [lower outer bolt holes used for lap-belts]). This means no seat-cushion cutting, no drilling in the floor-board & attaching a mounting-plate. And now a 6-point race harness.

Otherwise to mount a 5-point race harness- namely the anti-sub belt, it would require cutting of the lower seat cushion then either attaching to a floor-board mounting-plate or anti-sub belt mounting-bar below the seat or snaking it under the seat & wrapping it around the lower portion of the harness-bar


Shoulder belts:

- using the 3-bar slides, properly wrap/tighten the shoulder camlock-harness belts around the upper beam of harness-bar


Lap belts:

- using the bolts/washers, affix the lap camlock-harness belts to the lower outer bolt-holes of the harness bar


My (former) setups...

driver's side:

- Simpson 4-point camlock-harness (single anti-sub belt was never used)

or

- Schroth 6-point camlock-harness (anti-sub belts thru upper seat cushion, fastened to lower inner harness-bar bolt-holes using i-bolts & the anti-sub belts' spring-loaded mounting bracket clips


passenger's side:

- Simpson 4-point (single anti-sub belt was never used)

- Schroth 4-point camlock-harness (never acquired a 2nd set of anti-sub belts)

 

[titaniumdave]

These are the 2 sub belt mounts I have designed and built. Either can be used with 5 or 6 point sub belts. I feel this is better solution than the 'sit on' sub belt mount because of the angle of the seat back and torso in the NSX as opposed to a sports racer where one is less vertical.

http://www.nsxprime.com/forum/showthread.php?t=85880

Dali sell the stock seat part, I have both in stock if you want to purchase from the original designer/manufacturer. Feel free to PM me if you are interested.

Thanks
Dave

 

[Roger59]

Has anyone thought about drilling holes in the rear firewall just below the glass and installing I bolts with a backing plate to attach shoulder straps to?

 

[titaniumdave]

I don't think there is enough structure to support one in an accident, unless it's tied into the roll over structure. Like a harness bar...

 

[silver2002]

not that i know of; it's not that big of a hole.

edited