RECARO Bucket seats with Schroth Quick Fit ASM 4pt safety harness - mounting points

[ven0m]

Hey guys, I have a more track related question. A while back I fitted my Recaros with a 4pt safety harness from Schroth. Now I just wanted to ask if the way I fixed it in the car is correct?.

Some installed it like me (option A) and some went for the B pillar (option B). Is there any mayor difference in safety regarding these two mounting possibilities? One is connected to the seat and the other to the chassis, but what does that mean in practice (in an actual accident)?



Options on mounting the driver side left hand lap belt pig-tail of the 4pt harness:
Option A: On the seat - Mounting on the bolt of the OEM 3pt belt latch point on the driver seat left hand side. This is how I did it:









Others that went this route:



Option B: On the B-pillar - Mounting on the bolt of the pre-tensioner on the B-pillar. This includes cutting the trim of the B-pillar.









Others that also went this route:

[ven0m]

A few different schematics from Schroth that show both the Quick Fit and Rally4. Lap belts on both versions seem to go to the seat and not the B pillar - but later in the installation manual the pictures always show the mounting points on the chassis, which is confusing?!





Also some general schematic regarding recommended angles. And if you consider the angle of the lap belt then connecting it to the seat and not back on the B-pillar is more in-line with the recommended angle. or am i mistaken?

[koolade9]

Running a harness like that is a tragedy waiting to happen. Find yourself a fabricator and have them make you a proper harness bar. Or don't run one at all. The point of the harness is a safety device. Take a minute and run though the scenarios of what could happen to the occupant in that harness if the vehicle were hit from various places. (hint: don't count on the unibody staying rigid in an accident)

[badbluers4]

I think most clubs require the Hans with that harness is that correct?

[koolade9]

I think most clubs require the Hans with that harness is that correct?

Most clubs won't let you run that type of harness at all. Hans (or equivalent) is required by some organizations, but it hasn't become a standard (yet). It's a great idea to run one regardless. Get the sliding tethers

[ven0m]

Running a harness like that is a tragedy waiting to happen. Find yourself a fabricator and have them make you a proper harness bar. Or don't run one at all. The point of the harness is a safety device. Take a minute and run though the scenarios of what could happen to the occupant in that harness if the vehicle were hit from various places. (hint: don't count on the unibody staying rigid in an accident)

koolade, due to what I reasearched prior to purchasing the belt I decided in favour of the QuickFit.
If you can take the time and read what I found, I would gladly like to hear your thoughts about it.


I don't know if you know the manufacturer Schroth. They supply their harnesses for various types of motor-sports, including F1, WRC, etc. With the harnesses that are dedicated to street cars, that can be used on the track or at rally events, they also provide the appropriate TüV and ECE certification, which is mandatory in most EU countries. With that TüV and ECE the harnesses can also be used on various track events. To get this certification in Germany, various crash tests have to be performed.

But that is all nice in theory.

In practice at the end of the day, it's my neck that is going to snap if I crash - so I did a lot of research:
1st thing as you mentioned - harness bars, which raise the angle of the shoulder straps upwards, to prevent compression of the spine when the belt tightens in the event of a crash.
I don't have a problem with this angle, due to the holes in the bucket seats placed higher and myself being a bit short - I'm around 5'8'' (I won't say very short :P ) - the shoulder straps leave my shoulders in an upwards angle towards the holes in the seat - thus the holes acting as a harness bar to prevent spine compression.
2nd thing as with any 4pt harness is the missing 5th belt (Anti-Sub belt) that goes between your legs - this prevents the body slipping under the lap belt in the event of a crash.
With the Schroth you get the Patented ASM technology - flexible fibres that in the event of a crash let the body lean forward a couple of degrees, before slowly tightening (with this they also reduce the inertia on the body). When the upper body is tilted slightly forward it cannot push the pelvis under the lap belt. With this ASM technology Schroth quick fit belts are the only 4pt safety belts that can also legally be used on the road. This means they also comply with the E13 regulation here in the EU.
3ed thing is the use of any harness type, be it 4pt, 5pt, 11pt (I'm exaggerating here) WITHOUT a roll-cage, which is very dangerous in the event of a roll-over of the car. Because if the roof is pressed in and your head gets squished, because it can't "fiddle" out of the way due to the static belt.
I take this danger into account as the bucket seat headrest is a lot higher above my head and in the event of the roof coming down, the seat would be folded back, also allowing my body to move/break backwards. But honestly I'm not intending to flip my car any time soon - if I have to, I will rather do that with a dedicated track car, fitted with a proper roll-cage.
Bonus:
An added bonus is also that the quick fit integrates into the existing safety system of the road car. Because it plugs into the OE female connectors, the air-bags and tensioners are regulated normally as if using the OEM 3pt harness.
Audi has only the pre-tensioner at the base of the OEM 3pt harness, so tat is useless for the QuickFit. But Mini and BMW have an added tensioner on the female lap-belt connector, so in the event of a crash this would also tension the after-market harness like it was the OEM belt.

Here are actual crash tests of the QuickFit and the ASM technology:
https://www.schrothracing.com/sdocs/...Crash_Test.wmv
https://www.schrothracing.com/sdocs/SchrothASMII.wmv

VAG installation instructions:
https://www.schrothracing.com/docs/V...structions.pdf


Sorry for the long post, but I wanted to share what I found when I was doing the research on harness options. What are your thoughts on this subject?


@badblue: the QuickFit and other harnesses from Schroth can easily be combined with HANS devices, but can also be used without. At events where a HANS device is mandatory, there are also various other regulations: roll-cage, fire prevention system, etc.
Depends on the event. My current over all track time is about 2-3 hours per year, so not much, just the occasional open track day or driver training with instructors. If I manage to get more free time to attend the track, I would also fully dedicate a second car just for this purpose.

[koolade9]

When I was young and stupid, I used to run those exact harnesses in my DSMs & Evo. I ran a similar configuration in my A4 for awhile as well.

I'm not going to argue with you about your safety. I ride motorcycles too, so put me in the camp of 'dress for the fall, not the ride'.

I'll give you three scenarios:

1. You're rear ended and the chassis tacos just a bit, you've now lost shoulder support at a pretty critical moment in time. A hans might save your neck until your helmet collides with the steering wheel.
2. You're t-boned at the rear driver side door, those mounting points will effectively tighten that harness against you. How far do you think it can squeeze your chest and compress your spine until something gives?
3. Same as above, but imagine you're hit, hard. Picture yourself strapped in...now move the rear mounting points 1' towards the passenger side of the car, while not changing the length of the belts. Something has to give, so which will fail first...the seat, your back, or your neck?

The quick-fit harness will keep you in your seat while you're driving. A proper harness/bar setup will help keep you alive too.

Here's a couple examples of wadded up RS4s...in both of these, the passenger compartment wasn't breached, so perhaps the quickfit schroth setup would work...your call. Not in my car.

Clicky click

[ven0m]

Now that's a not so pleasant sight with the white RS (I hope I never see my car in such a shape). I saw the other black RS that rolled at Wiloow springs, also ugly and (from my impression) mostly due to driver error (even before entering the first turn at the beginning of the video you can see rapid and short steering inputs that unsettle the car at high speed). I had one accident with my car so far, but it was on the road at about 50mph - so nothing dramatic thankfully.

By no intent would I want to argue. The fact that you voice your concern when it comes to my safety makes me feel thankful and gives me a different perspective than what I had in my mind.

I thought about the three scenarios which you describe and I'm thinking the following:
1.) In the case of being rear ended so hard that the car frame is actualy compressed, wouldn't the airbag deploy which would prevent my head from slamming against the steering wheel?
2. & 3.) I believe in this case the first thing to give will be the seat as the holes where the belt passes through the bucket seat are it's first point of contact, my shoulders are lower that the holes, so also when the belts travel down my shoulders and chest they are still in an upwards angle. Added to this, the seat is still foldable, so it's not as strong like a fixed bucket race-seat, which means the hinge point is also the weakspot of the seat and I believe that my torso is more rigid than the hinge of the Recaro - in the case if a pulling force would be applied.

These are just my initial thought as what would happen in those events, but of course anything can happen. Lady luck can be in your favour and you can come walking out of a fireball crash with no scratches, or you can be in an F1 monocoque with the HANS and XY safety gear and a small pebble would kill you miserably.

I'm well aware that by no means the 4pt harness in a standard road-car is a substitute for a full roll-cage, harness-bar and 6pt harness with a HANS device.
But is the Schroth 4pt actually more dangerous than the OEM 3pt belt? Taking into account proper installation, proper belt fixing angles, sport buckets, OEM mounting points, various crash test, recieved certification, 40years of racing history, etc.


Would this combination (taking all the above facts into account) result in:
a) Improved car control due to static belts holding the driver in the seat - with retaining the cars basic safety features (not improving them)
b) Improved car control due to static belts holding the driver in the seat - with reduced safety features due to the harness