Seats, harnesses and HANS

Nuddy · Postby **Nuddy** » Tue Mar 07, 2017 12:12 am

I was a spectator at Wakefield on Sunday. It was the first time I have seen Wakefield and thecfirst time I have seen a MX-5 club event.
I intend to do club track days and probably supersprints in 2017 and maybe MX-5 Cup in 2018.
I observed many track day MX-5s using standard seats and lap/sash belts and some with racing seats, harnesses an maybe some with HANS.
I am wondering if i can use a 6 point harness and the HANS with a standard seat. I see that race seats have apertures for the belts.
Could I sew loops onto a standard seat for the shoulder straps? What about the crotch straps, do they go through the seat?

The American · Postby **The American** » Tue Mar 07, 2017 5:10 am

If you do get on to the track, you will definitely want a good seat. They make a huge difference to how you can drive and steer through corners - as you don't need to brace yourself with the steering wheel.

The added benefit is that they generally accomodate the belts. The crotch belts do go through the seat.

Apu · Postby **Apu** » Tue Mar 07, 2017 10:45 am

Don't use a harness with a standard seat. You won't be able to modify enough (within reasonable cost) for it to work with a harness.

I would go - race seat with lap sash, then race seat with harness...not the other way around.

Magpie · Postby **Magpie** » Tue Mar 07, 2017 11:00 am

You have the option of using a neck collar like these http://raceline-racewear.com.au/omp-k-style-neck-support.html and for the seat belt http://www.proquip.com.au/products/cg-lock.html

Vat · Postby **Vat** » Tue Mar 07, 2017 12:07 pm

The CG-Lock is a great little addition - I run one with the stock seat and once you get it properly set you're nicely pinned by the hips so you don't need to brace your legs as much. Top half of the body still moves around though.

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MX593 · Postby **MX593** » Tue Mar 07, 2017 3:49 pm

In my NB I use a 5 point harness and the seats out of a NC (with only slight modification of attachment to NA seat rails). The harness clips to eye bolts through the transmission tunnel, the stock lower seat belt bolt, a bolt through the seat base and the shoulders to the roll bar. All works well and is an effective and comfortable street/track set-up. Race seats are expensive, dam uncomfortable and they make getting in and out again really hard for a guy with crook back and knees. When I'm strapped in I don't get thrown around at all and I use a neck ring to stop my head getting slapped around. Love to have a HANS and matching helmet, but they are so expensive it's not funny. Yes, yes, yes save your life ect, ect, but who wares them on the road where there is a much bigger risk of having a serious crash?

RS2000 · Postby **RS2000** » Wed Mar 08, 2017 9:22 am

I haven't used one, but if a CG lock only locks the lap belt, then I'd say a better way is to just use the in-built inertia reel lock.

If you haven't got a harness, snap pull the sash belt to make it lock, then holding it locked, put the buckle in the latch. You will require a few goes to get the length right, with the length short enough for the lap & sash to be tight on your body. When done up, & with no play for the belt to retract & unlock, it holds you quite well.
I did this for hillclimbs & supersprints before fitting a harness.

david_syd_au · Postby **david_syd_au** » Wed Mar 08, 2017 9:39 am

MX593 wrote:...
Love to have a HANS and matching helmet, but they are so expensive it's not funny. Yes, yes, yes save your life ect, ect, but who wares them on the road where there is a much bigger risk of having a serious crash?

Road and track are very different situations.
On the road you use the lap sash belt, which is designed to have some give, you likely have a steering wheel air-bag as a last resort, and you don;t have the additional weight of a helmet on your neck in a crash.
In a race car, the harness stops the drivers body from moving around as much during normal use and in a crash, but contributes along with the weight of a helmet, to the potential for over extension of the neck in a crash. A frontal head restraint (FHR), like a HANS, is intended to counter that.

To the OP, if you plan to buy a helmet, make sure it has provision for FHR tether posts, for the future. I believe that anyone switching to a harness from the standard belts should also start using a FHR at the same time.

Guran · Postby **Guran** » Wed Mar 08, 2017 9:53 am

Nuddy wrote:I was a spectator at Wakefield on Sunday. It was the first time I have seen Wakefield and thecfirst time I have seen a MX-5 club event.

Great that you made it down. Did we talk at all? I spoke with heaps of people on the day, many of whom I've not met before. Hard to keep up with all the new names (and forum nicknames)!

Nuddy wrote:I observed many track day MX-5s using standard seats and lap/sash belts and some with racing seats, harnesses an maybe some with HANS.

Yes an increasing number of us are using HANS (or similar). They are being strongly encouraged by CAMS.

Nuddy wrote:I am wondering if i can use a 6 point harness and the HANS with a standard seat. I see that race seats have apertures for the belts. Could I sew loops onto a standard seat for the shoulder straps? What about the crotch straps, do they go through the seat?

Not a good idea to do that for a few reasons. Firstly, a standard seat does not have a hole in base for the crotch strap - no problem, you can use a 4-point harness (I have done so for years). Secondly, there is no aperture in the seat back for the shoulder straps to be held in place - in a frontal impact, the straps can slide off your shoulders. Thirdly, sewing loops onto the standard seat will hold the straps in place for easy access but are unlikely to be strong enough (including the seat material) to hold during an impact.

It's not recommended to use a harness without a HANS (or similar). The reason is that in a frontal impact the harness will hold your body much more than a standard lap sash belt, but your head will not be restrained. Your head & helmet are very heavy, and the absence of a HANS can lead to very serious neck injury or death.

I agree with Bryan's (Apu) recommendation. You can start with standard seat and standard belt but you'll be sliding all over the place in the seat. First upgrade should be race seat with standard belt which will keep you firmly in place. Make sure the lap part of the belt is fed through the lap aperture of the race seat, so that the belt sits low and tight across your abdomen. The tip for using the inertia lock is a good one too. When you want to upgrade to a harness, you should match it with a HANS and compatible full-face helmet.

I'm guilty of not following this advice in the past, especially when I first got started. But I bought myself a HANS (and compatible helmet) as soon as I realised the risks and judged that against the high frequency of my track activities (~20 days per year).

Nuddy · Postby **Nuddy** » Wed Mar 08, 2017 9:59 am

Just a pedantic technical point. Head back is neck extension. Head forward is neck flexion.
FHR prevents or minimises neck flexion injury and the less common rotation injury.
High back seats prevent or minimise neck extension injury.
Whiplash is clinically called a flexion-extension injury.

david_syd_au · Postby **david_syd_au** » Wed Mar 08, 2017 10:09 am

Guran wrote:..
But I bought myself a HANS (and compatible helmet) as soon as I realised the risks and judged that against the high frequency of my track activities (~20 days per year).

... and high risk driving style :twisted:

Nuddy · Postby **Nuddy** » Wed Mar 08, 2017 10:19 am

Thanks Guran
I don't know if we spoke. I just spoke to one or two people then caught up with Phil Mayo who I know from sailing at Wangi.
I watched the 3 MX-5 cup races and some of the track day groups.
I think i will do track days and hillclimbs this year and maybe some supersprints. Maybe some MX-5 Cup races late in the year if I can get below 1:16
I am getting a CAMS approved roll bar next week. I was hoping to retain the standard driver's seat for comfort and convenience as well as legality for daily drive but i won't sompromise on safety so i guess ill be getting the full package, seat, 6 point harness full face helmet and HANS.
I have entered for the hillclimb on 30th April. I would like to do the track day on 23rd but have a family commitment that i probably can't get out of.

davekmoore · Postby **davekmoore** » Wed Mar 08, 2017 10:04 pm

As far as I know you can use a race seat on the road as long as it enables you to use a normal seatbelt. Add an NA stalk bolted to the trans tunnel. Remember to reinforce the fitting under the tunnel. It sounds like you already know why you wouldn't just use your fixed harness on the road without a HANS device.

You could also bolt standard runners on the bottom of your race seat, thus making it pretty easy to swap seats. Bear in mind the screw threads in the floorpan aren't as tough as the threads in the bolts, so you may need to get your Helicoil kit out after a while. This arrangement might also sit you too high, especially if you're going to fit a rollbar and want your helmet to fit under it.

Nuddy · Postby **Nuddy** » Thu Mar 16, 2017 12:41 am

I have ended up with a Sparco Sprint V seat, Sabelt 6 point harness, Simpson Hybrid Sport forward (and lateral) head and neck support and Racelid Turismo SA2015 M6 helmet.
I was going to get a Stilo ST5R rally full face but there is no stock. I initially bought a Sabelt Titan seat but it would not fit in the MX-5.