Bolts for mounting jon foz subframes

[Louis]

Hi all,

What size bolts do I need for mounting jon foz frames? X-low variant.

Cheers!

 

[Krarl]

I just used some M8 12.9 tensile bolts with the original nuts underneath with some good solid washers on top.

Theyve stopped letting people on track without washers on seats now with all these people snapping seats and s**t

 

[Louis]

I just used some M8 12.9 tensile bolts with the original nuts underneath with some good solid washers on top.

Theyve stopped letting people on track without washers on seats now with all these people snapping seats and s**t

Sweet, was always going to use 12.9 just wasn't sure what size. Around 50mm in length or?

 

[Usr117063]

Fully threaded as well. I put a partial in there and realised Id started threading the rest of the bolt, just held the gun open until the bolt snapped. 12.9 as well

 

[Louis]

Capheads? Don't fancy hex-heads.

 

[Usr117063]

I used capheads

 

[Usr117063]

What seats are you going for?

 

[Louis]

What seats are you going for?

I already have a pair of Pole positions and FIA side mounts. Just waiting for a sunny day!

 

[frayz]

I already have a pair of Pole positions and FIA side mounts. Just waiting for a sunny day!

Can you post some pics/how you get on mounting these. I’m also waiting for a sunny day for mine.
You fitting the 3 point belts too?

 

[Louis]

Can you post some pics/how you get on mounting these. I’m also waiting for a sunny day for mine.
You fitting the 3 point belts too?

Yeah I will post some pictures in my build thread!
I've bought a pair of 206 rear seat belt buckles in preparation. Only £6 posted

 

[frayz]

Yeah I will post some pictures in my build thread!
I've bought a pair of 206 rear seat belt buckles in preparation. Only £6 posted

Have you made brackets up to bolt them
Up to?

 

[Louis]

Have you made brackets up to bolt them
Up to?

Nope, they're on a belt buckle and I'll mount them straight to the subframes. I'll be making a bracket out of some steel to keep them directed towards the hole in the seats at some point.

 

[JamesBryan]

I used 50mm.

With cap heads though they're not fully threaded after about 25mm so worth noting.

 

[Louis]

I used 50mm.

With cap heads though they're not fully threaded after about 25mm so worth noting.

Nice one cheers.

 

[Mertin]

Nope, they're on a belt buckle and I'll mount them straight to the subframes. I'll be making a bracket out of some steel to keep them directed towards the hole in the seats at some point.

It isn't advised to bolt harnesses to a subframe, I know it is done by others. Its preferable to have the seatbelt anchor point seperate from the subframe. In the unfortunate event anything happens to the subframe bolts, least your not going with it.
Also best to use penny washers for the cap screws rather than normal washers

 

[Louis]

It isn't advised to bolt harnesses to a subframe, I know it is done by others. Its preferable to have the seatbelt anchor point seperate from the subframe. In the unfortunate event anything happens to the subframe bolts, least your not going with it.
Also best to use penny washers for the cap screws rather than normal washers

Surely if the crash is hard enough to rip your seats off the subframes you're screwed?
Could you recommend another location for the seat buckle to be mounted?

I've bought some 12.9 M8X40 capheads, thick washers, repair washers and 8.8 nylocs. I plan on using standard seat nuts then a nyloc on the back (Overkill but may aswell).

 

[JamesBryan]

The OEM seatbelt is attached to the seat which is then attached by 4 bolts holding it down 🤔

 

[Mertin]

Surely if the crash is hard enough to rip your seats off the subframes you're screwed?
Could you recommend another location for the seat buckle to be mounted?

I've bought some 12.9 M8X40 capheads, thick washers, repair washers and 8.8 nylocs. I plan on using standard seat nuts then a nyloc on the back (Overkill but may aswell).

The OEM seatbelt is attached to the seat which is then attached by 4 bolts holding it down 🤔

Just going by comments from MSA Scrutineers at events when they have asked competitors to change
For the inner anchor point use an eye bolt and a spreader plate mounted below the car
Outer point, use the bolt and threaded hole that was used for the lower seatbelt mount and a Schroth B23A eyelet which can be bent into which orientation is required

 

[robmuns]

Have you made brackets up to bolt them
Up to?

I've used the buckles from the rear seats.. They come apart and give you a nice bracket with buckle attached to it which I've sat on top of the Jon foz subframe and then bolted through both with a spreader plate underneath.

May look into a way of mounting the original buckles with the pretenioners so they also move with the seat as they slide forward and back but the way I've done it atm works perfectly well tbh

 

[frayz]

I've used the buckles from the rear seats.. They come apart and give you a nice bracket with buckle attached to it which I've sat on top of the Jon foz subframe and then bolted through both with a spreader plate underneath.

May look into a way of mounting the original buckles with the pretenioners so they also move with the seat as they slide forward and back but the way I've done it atm works perfectly well tbh

I want something that moves with the seat really. I have a few ideas, but need to look at what others have done.