fizzer

I was looking through some old posts on harness installs and decided to go with a Schroth Rallye 4 ASM harness for autocross use only. After installing though, it seems like it would be fine for track day use as well.

I had originally planned on using the child safety latches with quick connect fittings, but after popping out the rear seat, I decided to mount directly to the rear passenger seatbelt bolts, the straps come up around the rear-sides of the rear seat.

Here's why I'm thinking they should work fine in a crash:

- shoulder belts mounted to "crash worthy" fittings.

- In a front impact, the ASM feature releases the right shoulder harness to allow the torso to move forward and act like a stock seatbelt - ASM working as designed to prevent submarining.

- the remaining question is: in a rollover situation, will the asm feature release the straps to prevent serious neck injury? This could be tricky as I don't know what the release tension of the ASM fitting is comared to the body's resistive force.

Its not perfect, but I'm willing to bet its much safer than running shoulder belts without an ASM release in a car without a cage.

Does anyone think it still too risky to use for track days?

Another note about the stock seats, the rotor opening does make the belts pinch a tiny bit on the neck, but its not too bad for the short periods of an autox run or a track day session (20-30 mins).

Matt RX8

I've been investigating this as well but concluded the opening is too narrow. Ideally, the shoulder straps should be at least 6 inches apart or something. I would think that having the shoulder strap so close to your neck would be very bad in a crash. Imagine the one shoulder belt strips away and you are left with your neck taking the brunt of the seatbelt pressure instead of your shoulder.

It's too bad Mazda had to put the silly rotary opening in the seat.

RX8SpdDmn

I investigated the issue heavily and determined that harnesses should NOT be used in our cars without a ROLL BAR AND RACING SEATS. The roll bar for, as you mentioned, not allowing the roof to collapse on you and compress your spine. The stock 3-point will allow you to bend away. You need the racing seats for the holes in them. As you said, going through the center hole is too tight. However, going around the shoulders would give the straps the opportunity to slip down around your shoulders.

It sucks! But I use the stock 3-point system right now with Schroth clavical pads. I do the seat belt lock trick to keep me firmly in place. Back the seat up and snap-lock the belt. Hold it locked with your body while you either pull the seat forward (one hand on release lever and the other on door handle or steering wheel), or push the button if you have a power seat. Once you fine-tune this, it will keep you tightly in place, even to the extent of making it hard to breathe, if you like. It's way better than that crappy CG Lock.

fizzer

Thanks for the feedback. I'll use them for auto-x only.

I did do a brief test ride after I installed the harness and the increased feel from having the two shoulder belts is significant. I've used the seatbelt locking trick (works great with the power seats) in the past and it is fairly good, but pales in comparison to the feedback and steadiness the real shoulder harnesses provide.

RX8SpdDmn

I agree 100%. I WISH it was safe for track. If I were gonna keep my car, I'd get an Autopower roll bar (<$400!) and proper racing seats so I could use harnesses. However, My lease will be up in a year, so that makes no financial sense.

Matt RX8

Sunday April 2nd, CVO track day at Gingerman $150. Every school needs more rotaries.

What are you replacing the RX-8 with?

RX8SpdDmn

Working on that... 75% chance that it'll be an Elise. 15% chance that I'll buy my car out at the end, 10% chance that it'll be something else all together.

dannobre

iTrader: (3)

Funny I don't know what you problem is with the CG lock? It works well if you install it properly It works consistantly for me............

TeamRX8

iTrader: (25)

autox requires you to use your upper body due to the extreme transitions and turning as compared to a track, IMO a track harness does more harm than good in anything other than a true racecar with super quick ratio steering

fizzer

I have full range of arm motion with the harness... I don't quite get what you're saying. As long as you position the seat correctly, its fine. Its even more beneficial due to the extreme transitions as you stay fully planted and don't get tossed around.

willhave8

Fizzer, does your harness come through the center hole or around the seat?

RX8SpdDmn

It only locks the lap belt. Not the shoulder belt.

TeamRX8

iTrader: (25)

ou can use the OE safety catch to do both, put belt on and slide the seat back, then do quick snap pull on the shoulder strap, the OE safety latch kicks in if you do it right, hold pressure on the strap while moving the seat forward to pull both the lap and shoulder belt tight against your body, takes some practice to find just the right position and belt slack before sliding forward, I can pretty much nail it on every try now, I never get thrown around doing it this way, and you probably need to be a passenger with a top level autocrosser slinging a well setup car back and forth through a slalom to understand what I mean about needing upper body movement to help turn the car, a well setup Stock Class car pulls about an 8G/sec transition rate ... comparatively, the manuevers and transitions at a track are much slower but are sustained for longer periods of time

fizzer

Through the hole. Around the seat would have the possibility of slipping off.

Paul_in_DC

The shoulder belt locks when you hit the brakes for the first turn.

Don't use a 4-point harness through our seat for track days because 1) as close as the straps are on your neck, a side impact could easily break your neck, 2) on the track you really need a 5 or 6-point harness to prevent the shoulder straps from pulling the lap belt up onto your torso, risking major soft tissue injuries.

I'd love to have a true harness for track days, but that means a 5/6-point harness, which means different seats, etc etc etc. Maybe in a year or two...

OdinGuru

Another alternative to the "lock" method is to use an H-clip (see picture below). These are cheap and not too hard to find (used for baby seats). I install this at the door so it ties the part of the belt going to your sholder to the ~6" of belt that is leading to the retractor. The result is that the belt no longer retracts and stays a completly fixed length. I usualy adjust this at the begining of the day so that I have to breath in and fight a bit to buckly the belt, that way it's tight enough that it realy holds down both my torso and lap. I find it's easier to get tighter this way than trying to move the seat.

I'm a firm beliver in some kind of additional bracing. I know for me and friends of mine, it has dramaticly improved our car control. It's difficult to have precice steering and throttle control when you are desperately trying to hang on to the wheel and brace yourself with a leg. I'd love to have a full harness, but like most others, the full seat and roll bar you'd need to do it safely isn't realy a viable option. Adjusted properly the H-clip works very well (thanks to the design of our seats), and I actualy feel more secured than in some of the less ideal full harness cars I've been in.

savedsol

I'd love to see the Schroth Quick Fit for our car. I do believe the rollover scenario is pretty lose-lose either way. You're flopping around like a rag doll in there... no guarantee you're torso will fold to the center of the car.

http://www.schrothracing.com/products/Tuning

The Ralleye 3 might be the best option, just like the QuickFit.

CosmosMpower

I use the CG-Lock and it works fine for me. I can't drive with my upper body restrained and I'm skinny so the biggest problem was my rear sliding around and using my legs to brace to keep me in place when they should be operating the pedals but that's just me.