Feasibility of 4pt rollbar and racing seats for dual duty car

[calubi]

Thanks! Some interesting points there. When was this published? They cite a 2002 study. I'm curious how much of this would change, if anything, for modern cars, especially the stats on 3pt systems and prevalence of head to doorframe injury on rollover crashes.

[SYT_Shadow]

Originally Posted by calubi

Thanks! Some interesting points there. When was this published? They cite a 2002 study. I'm curious how much of this would change, if anything, for modern cars, especially the stats on 3pt systems and prevalence of head to doorframe injury on rollover crashes.

If you want to read the whole study, PM your cellphone if you have whatsapp or signal and I'll transfer the file.

[4play]

I had what turned out to be a pretty good solution in my GTS. I removed it because the left wing of the seat was rubbing on the door card, but otherwise it was perfect.

OMP WRC-R seat
Brey Krause Sub Bar
Brey Krause Side Mounts
Brey Krause Lap Harness Mounting Kit
Schroth Profi 2x2 FHR Harness
OEM GTS Roll Cage
OEM BMW manual seat sliders

The sub bar prevents the seat from being mounted super low, which means it must be mounted midway up the side mounts. This (coincidentally) perfectly aligns the seat belt slot in the WRC-R with the 3 point belt receptacle. You cannot adjust the height of the pretensioner or receptacle, so it's more of a coincidence than a designed fit.

I could run 3 points on street correctly/safely and 6 points with HANS on track correctly/safely. As mentioned before, the only reason I removed it was the rubbing on the leather of the door card + airbag warnings (which admittedly could be coded out with Euro M4 GTS settings).

Photos:

[SYT_Shadow]

Originally Posted by 4play

I had what turned out to be a pretty good solution in my GTS. I removed it because the left wing of the seat was rubbing on the door card, but otherwise it was perfect.

OMP WRC-R seat
Brey Krause Sub Bar
Brey Krause Side Mounts
Brey Krause Lap Harness Mounting Kit
Schroth Profi 2x2 FHR Harness
OEM GTS Roll Cage
OEM BMW manual seat sliders

The sub bar prevents the seat from being mounted super low, which means it must be mounted midway up the side mounts. This (coincidentally) perfectly aligns the seat belt slot in the WRC-R with the 3 point belt receptacle. You cannot adjust the height of the pretensioner or receptacle, so it's more of a coincidence than a designed fit.

I could run 3 points on street correctly/safely and 6 points with HANS on track correctly/safely. As mentioned before, the only reason I removed it was the rubbing on the leather of the door card + airbag warnings (which admittedly could be coded out with Euro M4 GTS settings).

Photos:

Right now I'm running a similar solution, except for the OEM GTS cage that is replaced by the BK harness bar, and the OMP HTE-R 400 halo seats.

[4play]

Originally Posted by SYT_Shadow

Right now I'm running a similar solution, except for the OEM GTS cage that is replaced by the BK harness bar, and the OMP HTE-R 400 halo seats.

Yep, OMP are among the few seats with wide enough lap harness slots to accommodate the 3 point belt male end.

Hoping to do One Lap this year and glad to know that I have a solution that actually works for street/track drivability beforehand.

[jmciver]

Originally Posted by calubi

Ah, sorry, missed it hiding behind the seat side looking at the pictures on my phone.

So it sounds like the trick is selecting a seat that allows proper alignment of the 3pt belts? Does such a seat exist? How about the Cobra Nogaro with the BK mounts and OEM sliders, retaining the stock 3pt mounting locations that move with the seat?

Assuming this can be sorted, would the 4pt rollbar be a huge concern for occasional street driving?

Another data point... This will be my setup in the not too distant future based on the Nogaro seat design that supports the stock 3-pt belt system on the street. I am still waiting on my Nogaro's to come in. I will be adding the Schroth Quickfit Pros (with 6-pt add on) for track use. But I don't intend to add a roll bar (did that previously on my E46 M3 street/track car and don't desire the roll bar in the F80 to retain utility on the street).

One added feature with the Nogaro setup is that the Nogaro's have been tested and "certified" by Schroth to be used with the Schroth Quick Fit Pro belts. And to answer your earlier question about the Schroth Quick Fit's being certified in the F8x, Schroth never did this official certification - probably because BMW did not offer a viable seat solution in the M3/M4 (even though the non-M seats in the F3x probably could have worked). However, from a practical perspective (and IMHO) the F8x is very similar (if not better) than the E9x from a stock seatbelt engineering design/safety perspective - so the Schroth QFP's should be fine in the F80.

So, IMHO, using the Nogaro's in the F80, with the Schroth QFP (the E90 version due to the similar dimensions between the F80 and E90), is a good setup for a street/track car - but of course not perfect. As what was mentioned above, there are A LOT of opinions about safety setups for street/track cars when it comes to seat and harness usage on the track and street - with some having an "all certified or nothing" safety approach to these types of setups. So you will need to determine your own level of safety comfort with your setup.

[BetrayMyWord]

Got my driver seat to Sparco Evo L, paired with Schroth 16.5 Profi II. Sparco seat base underneath so a bit of tilt towards left side.

No cage or harness bar now; using eye bolts in the rear seats' buckles. No it's not the ideal setup, but let's go from there. Maybe a GTS half cage later? Not sure about its price and the drilling to the car frame.

[calubi]

Thanks for the input! A lot to consider. You guys have some nice setups!

[Obioban]

Originally Posted by BetrayMyWord

Got my driver seat to Sparco Evo L, paired with Schroth 16.5 Profi II. Sparco seat base underneath so a bit of tilt towards left side.

No cage or harness bar now; using eye bolts in the rear seats' buckles. No it's not the ideal setup, but let's go from there. Maybe a GTS half cage later? Not sure about its price and the drilling to the car frame.

It looks like you're attaching to the LATCH child seat mount points-- they're only good for kids that are <= 35 lbs... I would NOT be comfortable mounting harnesses there.

[aBMWfan]

Originally Posted by BetrayMyWord

Got my driver seat to Sparco Evo L, paired with Schroth 16.5 Profi II. Sparco seat base underneath so a bit of tilt towards left side.

No cage or harness bar now; using eye bolts in the rear seats' buckles. No it's not the ideal setup, but let's go from there. Maybe a GTS half cage later? Not sure about its price and the drilling to the car frame.

I can sell you a roll cage so it’s safer, lmk

[aBMWfan]

Anyone in Cali willing to sell red m4 front seats? Lmk today

[4Y_stack_acceleration]

Originally Posted by SYT_Shadow

I would get the BK harness bar that allows you to quickly remove it, does not include permanent modifications and allows 6pt belts, hans device and fixed back seats.

Huge difference vs stock

Is it a PITA to install and uninstall with an F82? Without the ease of having rear doors.

Now considering a BK harness bar with a 5pt over Schroth QFP for a couple reasons - potential tech inspection issues at NJMP (though enforcement varies) and submarining (even though it's 'ASM', probably small chance it can still occur)

I imagine another (indirect) rollover safety measure might be sway bars?

[SYT_Shadow]

Originally Posted by 4Y_stack_acceleration

Is it a PITA to install and uninstall with an F82? Without the ease of having rear doors.

Now considering a BK harness bar with a 5pt over Schroth QFP for a couple reasons - potential tech inspection issues at NJMP (though enforcement varies) and submarining (even though it's 'ASM', probably small chance it can still occur)

I imagine another (indirect) rollover safety measure might be sway bars?

It would be harder to undo the bolts, but still doable. Make sure your driver and passenger seats are on sliders if you want to maintain access to your rear seats once race seats are installed up front. Bk has a great kit for that as well

[Theruleslawyer]

Originally Posted by 4play

I had what turned out to be a pretty good solution in my GTS. I removed it because the left wing of the seat was rubbing on the door card, but otherwise it was perfect.

OMP WRC-R seat
Brey Krause Sub Bar
Brey Krause Side Mounts
Brey Krause Lap Harness Mounting Kit
Schroth Profi 2x2 FHR Harness
OEM GTS Roll Cage
OEM BMW manual seat sliders

Was that a standard or xl? Trying to figure out the upper limit of seat size for the car. at 620 or 665mm at the shoulders the wrc-r looks like a pretty wide seat in that area.

[SYT_Shadow]

I use the omp htr-r 400, fits fantastic

[Theruleslawyer]

Originally Posted by SYT_Shadow

I use the omp htr-r 400, fits fantastic

How much room do you have to the door card?

[SYT_Shadow]

Originally Posted by Theruleslawyer

How much room do you have to the door card?

Plenty. It doesn't rub on the door card or the b pillar. Great seats.

[Theruleslawyer]

Originally Posted by SYT_Shadow

Plenty. It doesn't rub on the door card or the b pillar. Great seats.

Its a street car so no halos for me. Just trying to gauge how much room there is.

[4Y_stack_acceleration]

Originally Posted by SYT_Shadow

It would be harder to undo the bolts, but still doable. Make sure your driver and passenger seats are on sliders if you want to maintain access to your rear seats once race seats are installed up front. Bk has a great kit for that as well

It seems like the Brey Krause harness bar isn't compatible with the F82 rear seats. So I think I'll just delete the rear seats and put in a half cage. I realized I did more DEs this year than the times I've carried rear passengers, so I'm not losing out on much for my use cases. Should also unlock more storage by getting rid of that space and having a roll bar that lets you fit tires underneath.

Will be getting the BK seat sliders - thanks for the recco.

[phefner]

SYT_Shadow

Happy New Year!

Hey did Competition MotorSports set you up with the seat and mounting hardware? I’m thinking of going down this road and also geeking out and doing a cage. My M is quickly becoming a dedicated track machine.

[SYT_Shadow]

Originally Posted by phefner

SYT_Shadow

Happy New Year!

Hey did Competition MotorSports set you up with the seat and mounting hardware? I’m thinking of going down this road and also geeking out and doing a cage. My M is quickly becoming a dedicated track machine.

Happy New Year to you as well!

I used all BK hardware, plus the oem sliders, to mount the seats. Still happy with the results after many years of running this setup in the E90, E92, M3 CS, GTS1 and GTS2

[M3SQRD]

Originally Posted by SYT_Shadow

Happy New Year to you as well!

I used all BK hardware, plus the oem sliders, to mount the seats. Still happy with the results after many years of running this setup in the E90, E92, M3 CS, GTS1 and GTS2

Why did you remove the oem GTS roll bar? Was the GTS harness bar not at the correct height or concerned about running a roll bar on the street or a combo of both?