mx5cartalk.com

I'm guessing that I'm not the only one having a lot of trouble finding a way to get a race seat into an MX5 so that it can be dríven comfortably, i.e. without knees getting in the way when the steering is turned and with the head low enough to clear the roll bar with a helmet on.

I've found the best way is to take the seat out all together and sit on a cushion on the floor with my back against the rear bulkhead.

Unfortunately this doesn't give a lot of lateral support so I'm thinking about approaching a guy I used to race with who owns a fibreglass shop and makes race seats, to custom mould a seat to suit the NB floor pan (Is NA the same??)

Looking to see if anyone else is interested and would be prepared to share costs. Alternatively, if I get some made who might be interested in buying one.

Obviously any seat produced is not going to be FIA or ADR approved or but should be fine for CAMS competition up to state level racing.

Drop the floor pan.

davekmoore wrote:Drop the floor pan.

I don't really need to, leg room is more of a problem than head room.

Sitting straight on the floor give me more than enough head room.

Besides, in my case the car is still street dríven, so cutting up the floor-pan is not a viable option.

I'm not sure if a custom seat would get much lower or further back than my current setup.

Sparco Roadster on a slightly modified KazeSpec Engineering rail.

Okibi wrote:I'm not sure if a custom seat would get much lower or further back than my current setup.

Sparco Roadster on a slightly modified KazeSpec Engineering rail.

Could you post some pics of it in the car. Always happy to go with the easier option.

Also how wide is it? While I'm not as big as a whale, I'm not slim either!

I've eaten too many pies too, it's about as wide as low and as far back as possible.

If I get some time tomorrow i'll take some photos.

Except, isn't the Sparco Roadster discontinued? I think the closest to it now I'd the Marrad seats, which are based on the Roadster. But might be a bit pricey.

The Lotus Elise seats I had sat very very low but don't have harness openings. You could try the Corbeau seats that many Lotus owners upgrade to but it might need custom brackets to bolt directly to the floor.

Apu wrote:The Lotus Elise seats I had sat very very low but don't have harness openings. You could try the Corbeau seats that many Lotus owners upgrade to but it might need custom brackets to bolt directly to the floor.

No, the Corbeau LE Pro is too wide at the base to fit between the rear mounting points on the floor. This pushes it up off the floor into an uncomfortable position (for me, at 1.90m tall). I sold my Corbeau LE Pro 2 weeks ago to an Elise owner. And as tall drivers know, all seats we use have custom brackets.

One of my summer jobs is to prototype an aluminium seat and steel seat rails specifically for the MX5 (NA). I have spent too much time and money researching, buying and selling seats to have any reasonable alternative, and boy have I looked! For 6 years I have looked! And as a road registered car competing in a road registered competition category, I can't legally drop the floor pan.

In my mind I wanted to incorporate a quasi roll over structure into the seat frame so that I could eliminate my roll cage, and the associated issues of the seat bumping into it (currently I have an AGI). This should also provide a light weight alternative to a roll cage, and, as part of the seat, eliminate issues of specific CAMS ROPS requirements when ROPS are not required. But this will be tricky and will not be included in my first prototype.

My first prototype will be designed to fit inside the AGI cage and follow the shape of the floor, such that the driver will be on the floor with only a 3mm thick Al sheet between the floor and his (/her!?) bum. Side bolsters will be as low as I can get away with on the door side to avoid the seat pushing into my thigh on my throttle leg. The backrest will be adjustable in angle, as the seat base will only have fore/aft adjustment. This is the plan...I'd like to write more but a 4 year old is annoying me.

Why don't you go to a proper race seat and hard mount it in the correct location for you?

NitroDann wrote:Why don't you go to a proper race seat and hard mount it in the correct location for you?

Thats the plan, but I've tried a couple of proper race seats in there, a fibreglass shell type as well as a steel frame Corbeau and both foul the shoulder wings on the B-pillar, which looses about 50mm of rearward seat travel.

There may be a decent race seat that suits me, I just haven't found one yet.

Kirkey? They have none of these issues because they support your via the ribcage rather than around the shoulders.

Dann

PM Lightyear. He's a tall guy too. I know he has made himself at least one fibreglass/carbon seat to give himself more room. He may be able to assist?

NitroDann wrote:Kirkey? They have none of these issues because they support your via the ribcage rather than around the shoulders.

I like the look of the Kirkey seats. They are thin enough to sit low (well, for some of the various widths available), come with a reasonable range of seat to backrest angles, and are not too expensive or heavy.

BUT, they are not FIA or ADR approved. I have considered approaching Kirkey to get FIA approval (basically just a few tests on one example of the seat IIRC), but I would need to buy a seat from the states, be sure that the seat fitted quite well, then get them to test that model seat in that width.....not going to happen I imagine, and I don't want to pay to test their seat. Without FIA or ADR approval, it is possible to get a seat through scrutineering at a CAMS event if it looks like seats that have FIA or ADR approval. But my guess is that it might be difficult to get the quite unique looking Kirkey through. Having said that, I noticed a BMW E30 at the 2015 Australian National Supersprint Championship with a Kirkey...so it has been done. But this is where a well designed, MX5 specific, GRP bucket would make life easier.

However, with a seat I designed myself I would have much more incentive to have it tested to FIA specs (we have one official testing lab here in Australia, in Melbourne), and I know it would be as suitable and as comfortable for tallies as I could make it within the constraints I have, and that it would definitely fit the MX5. And if enough support existed from you lot out there, the cost of testing may be amortised over a number of seats.

When I used to work in the passenger rail industry, one of my many Engineering roles was to test seats, and modify some to pass the many varied requirements (most of which related to vandalism rather than safety). The FIA tests look pretty simple to me, so I'd like to think I could get through on the first go. I should probably contact the testing lab and get some prices.

Pretty sure club and state level CAMS events (and possibly national too) don't require FIA approved seats.

But its probably some peace of mind knowing that a seat has passed some formalised testing.

I've been told that gaining FIA approval on anything is hideously expensive, but I've never actually heard a $ amount.