Converting Single Full Width Roll Bar to Dual Bars on Mk2 Shell

[skinnymathew]

I took my double roll bar off some time ago and this week I finally sourced a pair of single roll bars at a reasonable price. I've started to weigh up the task of installing them and I've noticed that my shell seems to have a curved reinforcement bar embedded in the fibreglass and running from the upper seatbelt anchor points out to towards the edges of the cockpit. It looks like I'm going to have to drill a 52mm (minimum) hole through this bar on either side to fit the new roll bars; I assume this has been done before by others as this is a common swap and I'm not compromising anything in doing so?

[Chris1]

I took my double roll bar off some time ago and this week I finally sourced a pair of single roll bars at a reasonable price. I've started to weigh up the task of installing them and I've noticed that my shell seems to have a curved reinforcement bar embedded in the fibreglass and running from the upper seatbelt anchor points out to towards the edges of the cockpit. It looks like I'm going to have to drill a 52mm (minimum) hole through this bar on either side to fit the new roll bars; I assume this has been done before by others as this is a common swap and I'm not compromising anything in doing so?

I have thought about this with my early SRv8 and I know that there are brackets that need to be welded in
around the propshaft tunnel area, there were two types available, one for a single loop and one for two loops .
Adds up to a reasonable amount of work I would have thought and would be similar for your pilgrim ?
Obviously yours is a totally different set up and would be interested to find out more.
Chris.

[PhilG66]

Seatbelt anchor point bracket - am thinking of doing this on my mk2 too - need to also work out if with the curvature of the body whether you’ll have room to fit the escutcheons, etc, etc - might make this a job for next winter………

[dgosumo]

As noted by Phil666 the "curved reinforcement bar" is what provides the strength for the Seatbelt mounting. If you're going to drill right through it and you're using the standard seatbelt bolt on top of the shell between the seats then you need to fabricate a replacement heavy-duty mounting anchored to the chassis.

[skinnymathew]

As noted by Phil666 the "curved reinforcement bar" is what provides the strength for the Seatbelt mounting. If you're going to drill right through it and you're using the standard seatbelt bolt on top of the shell between the seats then you need to fabricate a replacement heavy-duty mounting anchored to the chassis.

There's a substantial bar running vertically from the chassis to the seatbelt upper anchor points. The curved bar meets it at the same place. Are you saying that it's the curved bar embedded in the fibreglass that provides the seat belt anchor strength, rather than the vertical bar from the chassis?

[PhilG66]

Checked on mine - the vertical bar glassed into the body is part of the seatbelt mounting points bracket - the horizontal bar takes the upper seat belt mount - the vertical bar is used to mount the seat belt reels to. So if you remove a large part of any of this bracket you could make the whole assembly considerably weaker unless you build in an additional structure to take the seat belt loadings in the event of an accident, hence DGO’s comment.

[dgosumo]

Checked on mine - the vertical bar glassed into the body is part of the seatbelt mounting points bracket - the horizontal bar takes the upper seat belt mount - the vertical bar is used to mount the seat belt reels to. So if you remove a large part of any of this bracket you could make the whole assembly considerably weaker unless you build in an additional structure to take the seat belt loadings in the event of an accident, hence DGO’s comment.

Yes that's my understanding. The mounting bolt on the top of the shell will (obviously in extreme - but that's when you need it) pull out of the shell. The long bar was put into the shell to pass the European (Dutch) approval for seat belt mounting that has been covered on this site a number of times

From page 4 of the Pilgrim build manual (Link): "Safety: Our kits are amongst the safest within the specialist car industry. We spend a great deal of time and money having our kits examined, tested and approved by various British and European road traffic authorities.The Sumo has been tested by Dutch road traffic authorities and has been granted full Dutch type approval. Seatbelt anchorage test were conducted to the rigorous requirements of ECE regulation 14.02 and passed with a comfortable margin. Various other tests have been conducted by the very strict German TUV authorities, including the Hydropulse test, before they grant their type approval."