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Discussion Starter #1
Where can you bolt a harness?

Harness recommendations?

I am thinking a TRW/Schrothe style which uses the stock bottom seatbelt bolts and then running back to the firewall with a spreader plate to handle the load.

Alternately, maybe a harness bar?
 

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Discussion Starter #2

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I'm one of those "no harness w/o a rollbar" kinda guys, but the fellas over at one of those "other" boards described an A-frame to support the stock roll hoop that also incorporates a harness bar. It seems like a really good idea to me, and I like the idea of a removable cross-brace for time trialing (although, I don't really know how easy the install/removal of the brace will be). See pic of the frame itself here.

From that point you should be able to use any standard harness with a wrap. Lap belts might find their way to seat mounting points. This all assumes that I'll be able to maintain the three-point reel for day-to-day use, which is mandatory for me.
 

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After spending some time in a 325i "race car" this weekend, I decided that having a harness is a good idea even for canyon runs. Randy, if you find something you like, perhaps we can start a group buy on it.
 

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Harnesses are usually installed using a harness-bar bolted to the normal rollbar.

The motorsport 'A' frame with diagonal for the S1 does not fit the S2 (lower rollbar, different thickness pipe), although I think Lotus Motorsport can do one.

The 'A' frame is not easy to install in the S2 and the official one (visible on some Lotus promotional images of the S2 Sport190) adds a little 'hoop' on top of the roll-bar where the driver sits. (probably for height regulations)

A harness bar is not difficult to install.

The lower harness bolts should be bolted through the rear chassis beam and NOT the floorpan as is only 2mm sheet aluminium and can't handle the load. Use spreader plates placed inside the (hollow) beam and bolt the harness to this.

This does require some minor cutting and peeling back of the glued aluminium sheet underneath the passenger compartiment to get the plates/nuts in place. Afterwards these parts should be pushed back and some glue/coating applied.

And yes: the floor at your feet and under the seats is only 1 sheet aluminium. It's not double-walled. What you see under the car is what you see on the inside..

Using the normal seatbelt points is possible, but the metal frame is not that strong and the seats are bolted into aluminium 'weldnuts' that are not very strong either.

Stress loading on these points when using a 4/5/6 point harness can be much higher than with the normal inertia belts and the seat can tear loose from the car.

Bye, Arno.
 

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5th point for harness?

Arno,

Even for us metric-impaired, 2 mm is clearly a thin sheet of aluminum. So how does a sub strap get bolted into the car at the floor? That's the one to keep you from sliding forward leg first and out of the other 4 points of the harness. Does it need another metal member installed into the chassis?

and on the same topic, do you notice any heel marks or rock impact points in the floor pan?
 

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Installing beams in the chassis is not possible. It's glued together and modifications are not allowed.

BTW.. Almost all damage to the chassis means it's a write-off. No repair work is allowed to be done on the chassis itself.

It's easy to write off an Elise by hitting a curb with the front wheel and tearing a wishbone pickup point on the chassis.

The options here are (I assume a 6-point, so 2 crotch straps.. works better for boys :D ), depending on what the manufacturer of the belt allows:

- Pull forward and bolt to the front chassis beam
- Pull backward and bolt to the rear chassis beam
- Attach to the seat rails themselves either directly or using a steel crossbeam bolted in place. (mostly used if the sliding seat rails are replaced by bolt-in rails, which already have holes)
- Attach to the seat shell

The seat bottom is only a few mm from the floor surface, so if you want to keep the seat movable (in case you keep the original sliders) then you can't really put much underneat the seat.

Usless trivia: small pebbles or bits of rock stuck between the seat and the floor make the floor resonate like mad.. Everyone gets that one while driving as small stones are thrown into the car by other cars. Scares you silluy the first time :D

Bye, Arno.
 

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It is unsafe to use a harness without additional roll-over protection?
 

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Nope if I were you I'd always use a harness in an elise you feel much much safer.

The harnesses in my S2 were just fitted to a harness bar, nice and simple - were only 4 point though - if you want 5/6 point you need to have a fixing plate put in the floor.
 

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Vantage said:
It is unsafe to use a harness without additional roll-over protection?
Well, it is unsafe to use an upper-body harness without any rollover protection (including stock sedans, IMHO). Note that the stock Elise has a roll-hoop structure that provides some amount of protection. The question then becomes whether additional structure is required in the Elise, and that seems rather debatable. Of the photos I've seen, some make it appear that the roll structure is indestructible, others leave me queasy - but not knowing the circumstances of those accidents makes it impossible to draw any conclusions from them.

The A-frame (without the additional forward brace) would seem to offer a good solution to minimally-intrusive additional protection and harness installation -- if it fits.

I suspect the SELOC folks can offer a more informed (if opinionated!) response.
 

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>>Of the photos I've seen, some make it appear that the roll structure is indestructible, others leave me queasy - but not knowing the circumstances of those accidents makes it impossible to draw any conclusions from them.

It's documented on another thread here but the rollhoop on the elise is designed to absorb energy not deflect it thus you will see pictures where it is damaged but more than likely the occupants walked out.

As my previous thread says, you're being seriously cautious fitting A frames and diagonal supports if you're only thinking of road and casual track use. I've never seen an S2 with a diagonal bar to be honest, or for that matter an A frame.
 

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moose said:
I've never seen an S2 with a diagonal bar to be honest, or for that matter an A frame.
I've only ever seen an A-frame in an S2 on the promotional pictures of the S2 Sport190, never in real life.

Seen a few on S1's though. On an S1 it's probably easier to fit because the roll-bar cover and window can be removed to install the upper clamp.. Difficult on the S2 with the glued-on window and frame. Probably requires cutting and re-glue-ing..

I think it's still a custom made jobbie done by Lotus Motorsport. They'll sell it of course, but it'll probably be serious money...

Reports I have seen on the S1 A-frame menion that the diagonal bar is very difficult to remove and re-install. Technically it's removable, but in practice it's just too hard.

Bye, Arno.
 

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Re: 5th point for harness?

Jay said:
and on the same topic, do you notice any heel marks or rock impact points in the floor pan?
Ah.. No.. There is always some floor covering in the foot area, which provides enough protection. The 'bare' aluminuim is a bit too slippery for my taste.

This floor covering (by default it was a rubber mat) has caused some problems for the current Elises though.

Water got between the aluminium and the rubber because of condensation and for instance leaks. This then resulted in a problem called 'crevice corrosion' where the water and aluminium over time formed an acid (auminium-hydroxide I think..). This would then slowly eat holes in the floor.

I guess the US cars will get a 'breathing' floor covering, so no water can remain trapped under the mats and cause this problem.

Cars with carpet floor covering did not show this problem because the carpet allows water to evaporate.

The aluminium sheet under the passenger compartiment is also 'creased' to make it stiffer. If you look under the car carefully you can see that the bends form a large 'X' in the sheet.

Real rock damage would be bad. Normal stones and such thrown up by the wheels don't cause problems (you hear them bounce under the car sometimes), but you definitely don't want to ground the car on boulder type rocks. These will seriously damage this part and it can't be replaced. (it's bonded to the chassis)

Bye, Arno.
 

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moose said:
As my previous thread says, you're being seriously cautious fitting A frames and diagonal supports if you're only thinking of road and casual track use.
I admit that it's a bit "over the top" :rolleyes: - and I'm not at all convinced that it's necessary for the Elise, but I need to see more technical data about the chassis/bar before ruling it in or out. I've seen too much automotive mayhem, and my head will be too close to the roll structure, to not want to find out more.

I also hope that my track use will be something more than merely "casual"!

Cheers.
 

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Discussion Starter #16
Just got off the phone with a guy that was asking about rollstructures for SCCA sanctioned track events. He was curious about what options there were for a real rollbar.
 

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Al - do you use SELOC? If not go on there and get some testimonials from people with harness bars :)

The harness bar is bolted securely into the rollover hoop and even with non-race seats (ie the ones with holes for the harnesses to feed thru it is secure). I did however go on to spend over US$3000 on some 340r seats for my S2, on grounds of comfort (due to LSS) and safety (harness fitting).

Rock impact - I know of one S2 that was written off after hitting some ornamental boulders at the side of the road. Damaged the suspension and it was goodnight for that particular Lotus.
 

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Randy Chase said:
Just got off the phone with a guy that was asking about rollstructures for SCCA sanctioned track events. He was curious about what options there were for a real rollbar.
From what I can tell, Safety Devices offered a 6 pt bolt-in cage that was FIA-approved for the Sport Elise (the car used in the Autobytel Lotus Championship). See Clements, Elise, Rebirth of the True Lotus, pp 71-73 (2003). But, alas, this was on the S1. No idea if it would fit the S2. What is encouraging (for those contemplating Club Racing) is that from the photos, there appears that there was no additional side protection required than that offered by the chassis tub.

Edit: Of course, the 6 pt cage won't fit because the rear clam on the Sport Elise is Exige-like. Perhaps a 4 pt cage without the rearward attachments might work? But at least it seems that Safety Devices can provide a head-start.

As an aside, Clements refers to the steel-roll-hoop as "RAC approved" -- who or what are the RAC? From context, I'd conclude that they are like our SCCA . . .
 

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Re: Re: 5th point for harness?

Arno said:
.

Water got between the aluminium and the rubber because of condensation and for instance leaks. This then resulted in a problem called 'crevice corrosion' where the water and aluminium over time formed an acid (auminium-hydroxide I think..). This would then slowly eat holes in the floor.


Bye, Arno.
Hi Arno
Have to correct this:
Aluminum hydroxide is no acid. It's a caustic alkaline substance.
Unlike metals like iron, zink etc. aluminum is pretty acid ressistant.(exception: anything cotaining chloride)
But unlike other metals it is easily dissolved in alkalis. This is why we use caustic soda for aluminum etching.
Crevice corrosion: in gap or crevice (0.1mm - 1mm) where water is not allowed to evaporate, water will absorb aluminum creating a caustic aluminum hydroxide solution. This was eating our footwells.

cheers,
Fabian
 

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To visualise my installation, I've shot a couple of pictures of it. I had and have no racing experiencing and no clue whether anything is sanctioned. It was fitted by my dealer (not by Lotus themselves).

Photo of bar at drivers side. Note the green paint which normally wasn't visible because the regular three point seatbelts had something mounted there


Another view of the bar. Note that the top of the harnesses are bolted on here


Here is the attachment of the right side of the passengers seat of the harness (attached to the chair). To the left is the pump for the inflatable lumbar support


Passengers side. Lovely green paint. Notice the Mitsubitshi to the left ;)
 
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