Any rules against frame modifications?

[BeerBudgetRacing]

I am considering widening the drivers opening for shoulder room.
I couldn't find anything that says you can't.

Any reason not to do it?

[DanW]

I had a local fabricator, Callouette Fabricators widen the roll bar forward braces and top chassis tubes on my Zink FF.

The outcome was excellent and gave me the space I needed. I can send photos if needed.

[BeerBudgetRacing]

Photos would be very helpful. I'm sure there are several ways to do it and pictures of one that works would be great.

Did you consider it expensive?
Do you think it "ruined the car" for others/resale?

Thanks

[DanW]

PM sent.

[Astro]

I have an fj1600 which was obviously built for slightly built drivers. I have to widen the drivers cockpit to suit my size. I have been thinking how best to do this without building a new chassis from scratch (which would obviously be best). My head with helmet comes too close to the top of the rollbar for my local regulations, as well my arms are not able to fit between my torso and the cockpit bars. So my solution is to have another roll bar made, higher, wider, and weld it to the outside of the original one. That way all of the bars coming from the engine bay will still be attached to the original bar, which will be attached to the new bar. Forward of the roll bar I plan to widen the cockpit bars to suit my wider shoulders, attached to original 'forward' roll bar( ahead of steering wheel). I would also like to add strengthening braces using 1mm plate bent & shaped, rollbar to rear chassis bars. I will also lenghten cockpit chassis members 100mm to allow for taller drivers. I find that this expands your market, should you decide to sell the vehicle at a later time. I have yet to cut apart my project, but I am itching to do so, At the same time Iwish to do it right without comprimising safety.

[S Lathrop]

There is no rule saying you have to leave the roll bar structure un-modified. But when you do, you now become the designer of the car and you have to make sure that your roll bar structure meets all the requirements of the GCR. It could be argued that you should have new homologation papers issued because you have modified a safety feature and the car no longer conforms to the original homologation application.

Also when you raise a roll bar, you are increasing the potential loads on the mountings of that roll bar at the chassis. So you may need to do a little engineering work to make sure that you don't create a roll bar failure point at the chassis and not at the top of the braces as most roll bars are.

[BeerBudgetRacing]

I have an fj1600 which was obviously built for slightly built drivers. I have to widen the drivers cockpit to suit my size. I have been thinking how best to do this without building a new chassis from scratch (which would obviously be best). My head with helmet comes too close to the top of the rollbar for my local regulations, as well my arms are not able to fit between my torso and the cockpit bars. So my solution is to have another roll bar made, higher, wider, and weld it to the outside of the original one. That way all of the bars coming from the engine bay will still be attached to the original bar, which will be attached to the new bar. Forward of the roll bar I plan to widen the cockpit bars to suit my wider shoulders, attached to original 'forward' roll bar( ahead of steering wheel). I would also like to add strengthening braces using 1mm plate bent & shaped, rollbar to rear chassis bars. I will also lenghten cockpit chassis members 100mm to allow for taller drivers. I find that this expands your market, should you decide to sell the vehicle at a later time. I have yet to cut apart my project, but I am itching to do so, At the same time Iwish to do it right without comprimising safety.

Astro, from what I've read the strengthening plates would be illegal in SCCA.
That is if I understand you and the rules I've read.

Other than the added weight of the second rollbar layer, good plan.

[BeerBudgetRacing]

There is no rule saying you have to leave the roll bar structure un-modified. But when you do, you now become the designer of the car and you have to make sure that your roll bar structure meets all the requirements of the GCR. It could be argued that you should have new homologation papers issued because you have modified a safety feature and the car no longer conforms to the original homologation application.

Also when you raise a roll bar, you are increasing the potential loads on the mountings of that roll bar at the chassis. So you may need to do a little engineering work to make sure that you don't create a roll bar failure point at the chassis and not at the top of the braces as most roll bars are.

Good perspective. I think you may be right about new homologation. Exactly why I asked.
Not a deal killer but something to think through. Thanks.