11 replies to this topic

[Haynes]

After advise on how to properly install race seats for a road going hill climber?  

 

Assuming side mounted seats with off the shelf brackets, the question is how to brace and support the floor?

 

I assume a couple of cross braces for the front and back fixings are required, welded into and attached to the exhaust tunnel / inner sill?

 

What thickness material should be used and what profile, ie is complete box section necessary?

 

I also assume 10cm2 pad for each fixing on the underside of the floor?  Are an other pads etc required?  

 

 

 

 

[Swift_General]

If it's for competition then you need to read the RAC 'blue book' as you will have to meet those requirements. Contains the regs you have to meet with drawings etc. Otherwise you risk building a hill climb car which doesn't meet the regs.

[nicklouse]

as above read the blue book.

 

2.2. Seats. All seats should be correctly located and

securely anchored in such a way as to allow no

movement in squab or backrest. When installing a

Competition Seat, carry out the following checks before

selection or purchase:

(a) Study the requirements of the vehicle concerned

and ask the manufacturer’s advice and

recommendations.

(b) Check that the seat is suitable for the type of

forces to which it could be subjected. These will

include fore and aft and lateral loadings.

© Check that the seat carries full instructions for

installation in your vehicle.

(d) Check that suitable mounting installations are

available from the manufacturer.

(e) Ask the manufacturer to confirm that the seat

frame is suitable for your Motor Sport discipline.

(f) If the original seat attachments or supports are

changed, the new parts must either be approved

for that application by the seat manufacturer or

must comply with the following specifications (see

drawing No. K32).

2.2.1. Supports must be attached to the shell/chassis

via at least 4 mounting points per seat using bolts with

a minimum diameter of 8mm and counterplates,

according to drawing No. K32. The minimum area of

contact between support, shell/chassis and

counterplate is 40 sq cm for each mounting point. In

Series Production Cars manufacturers’ standard seat

mounting points may be used. If quick release systems

are used, they must be capable of withstanding vertical

and horizontal forces of 18000N, applied nonsimultaneously.

If rails for adjusting the seat are used,

they must be those originally supplied with the

homologated car or with the seat.

2.2.2. The seat must be attached to the supports via 4

mounting points, 2 at the front and 2 at the rear of the

seat, using bolts with a minimum diameter of 8mm and

reinforcements integrated into the seat.

Each mounting point must be capable of withstanding

a force of 15000N applied in any direction.

2.2.3. The minimum thickness of the supports and

counterplates is 3mm for steel and 5mm for light alloy

materials. The minimum longitudinal dimension of each

support is 6cm.

2.3. Headrests. On all vehicles where it is not

mandatory (13) it is strongly recommended that a head

restraint in the form of a headrest be fitted, as near to

the driver’s/co-driver’s helmet as possible, to prevent

whiplash of the neck and spine in case of impact. It is

recommended that they comply with 13.

Fire Extinguishers

[James_eaton_thewholething]

Something along the lines of this.



Everything is 3mm thick steel, box section was 25mm x 25mm x 3mm. Points where the seat brackets bolt through are 3mm plate bent and welded

[Haynes]

I did look at blue book but was struggling to understand applying it to a min.

The only thing is seems to say about the actual mounting is the 2 spreader plates sandwiching the floor.

Is that really sufficient on a mini floor?

Does use of box section contravene blue book?

Another issue is the ribs underneath, my fixings fall pretty close, how do you get a plate of sufficient size and position?

And not being too tall the front of the seat needs to be almost inline with the front of the cross member so the front fixing could do with being on the cross member itself!

[Turbo Nick]

Did mine the same as the MSA kits you can buy from rally design and the likes

 

25mm cds tube, 3mm steel spreader plates etc.

 

 

 

 

 

Edited by Turbo Nick, 12 February 2016 - 08:09 PM.

[James_eaton_thewholething]

How tall are you ?

It doesn't mention in the rules you have to use tube or box section to make seat mounts. Some cars you can use existing seat mounts. Some people on here just weld spreader plates to the floor and bolt them in and get through scrutinering. Problem with that is the floor isn't very solid and seems to flex a lot

[Haynes]

I'm 5'6. Also not too keen on having seats right on the floor and lose visibility, as the car will remain road legal.

And precisely, a mini floor does flex hence the blue book not really pinning down suitable install in a mini.

[James_eaton_thewholething]

I'm 5'7 where my supports are the front of the seat hangs half way across the the cross member. I always found the regular position of seating uncomfortable. Used to get cramp in my right foot regularly. Now where the seating is my leg is only fully stretched out of the pedal goes right to the toeboard. Now if either the brake or clutch pedal do that I have issues. Depending on what seats you are fitting depends on how high you can sit. I like being quite low in the car but I can still see the front of the wings with ease, that's with the seats at its lowest setting.

The blue book tells you how they should be fitted for saftey and isn't car specific.

Can't you get the seat bases that mean you can use existing car mounts and are adjustable ?

What seats are you planning to fit ?

Edited by James_eaton_thewholething, 12 February 2016 - 10:39 PM.

[Haynes]

Thinking of sparco sprints but suggestions welcome. A pair of these should fit quite nicely as they're not too bulky.

[James_eaton_thewholething]

I was originally going to go with sprints but then spotted some omp ones going on eBay. I would say sprints are good and won't have to worry about them being too wide at the shoulders. I know turbo Nick has his so far back because of how wide they are and mine are staggered with the passenger one behind the B post so they would fit easier

[Juniors mini]

I have sprints in mine fitted with modified subframes, I had to buy the seat hinges the have the extended section that sits over the crossmember because if fitted with the factory ones I had to have the seat back all the way on the runners which I didn't like, adding these brackets allowed the seat to sit in the centre off the runners. Where I have my seat sitting it is very close to the b pillar, it could go back more if it wasn't for the rollcage.

Edited by Juniors mini, 13 February 2016 - 01:01 PM.