Question about CF Bonnets

[Aeris]

Can Carbon Fibre Bonnets be engineered?, i know just cars won't insure, but just curious about their legalities etc and if there are ways around them.

[MadManz]

Dont know why that is the case, as the bonnet is not a structual part of the car and is hinged, so i wouldnt have thought you needed it engineered.

but i may be wronge

[Ronin 09]

I would highly expect that you would have to try and engineer it, however you'll be knocked back. Bonnet behaviour is integral in an frontal accident, no way any engineer will allow it becuase of changed crumple characteristics, etc etc

[GTRgeoff]

Marcus, close but the issue is pedestrian accidents. CF not properly laid up with a layer of Kevlar will shatter and split in razor sharp shards, where the kevlar will hold it and make it fail more like aluminium, being more friendly to pedestrians. If you are thinking of having a CF bonnet consider the long term costs of paying fo medical care if you hit a pedestrian and injure them. State 3rd party may not cover it, or they may come after you for recompense.

[TracidTrax]

Can Carbon Fibre Bonnets be engineered?,  i know just cars won't insure, but just curious about their legalities etc and if there are ways around them.

cf bonnets look crap anyway, dont like the way the bonnet is black and the rest of the car is a different colour, looks crap imo

[r34_skyline]

hrmmm, but arent most cf hoods fibre glass with a layer of cf ?

[Ronin 09]

Marcus, close but the issue is pedestrian accidents. CF not properly laid up with a layer of Kevlar will shatter and split in razor sharp shards, where the kevlar will hold it and make it fail more like aluminium, being more friendly to pedestrians. If you are thinking of having a CF bonnet consider the long term costs of paying fo medical care if you hit a pedestrian and injure them. State 3rd party may not cover it, or they may come after you for recompense.

that was my etc etc

nah i really should have thought of that too

PS I note that we are now "GTR ENABLED" congrats you deserve it

[Menthu_Rae]

What about fibreglass bonnets - are they also illegal due to changed crash characteristics when compared to standard metal bonnets?

[GTRgeoff]

Fiberglass will be thicker and are usually chopped strand mat, therefore they will break up in a different way to CF or CF over fiberglass. You have to see the way CF shards, even off fiberglass, to really get a handle on it but from experience (not in an accident) it is sharp and can be painful. With the Kevlar layer in the CF layup it becomes part of the structure and changes it significantly. Kevlar is a titanium or tungsten thread coated with another product (can't remember) then made into mat.

Marcus, thanks for that. I'm happy especially when I saw the $12K in receipts for the engine from Racepace and Argo. WooHoo. Check the for sale thread for more info..

[Aeris]

Thanks for all the replies guys, i was wanting to get one mainly because i liked the look of one particular design, but if it can't be engineered or made legal, i don't wanna know about it hehe, perhaps i'll look further into modifying my stock bonnet with a scoop/airflow type setup, i heard somewhere that these aren't illegal, correct me if i'm wrong.

[Winner1]

Aeris hey mate CF can be engineered 100% . mah mate did it on his skyline ... he had the scoop one , but he gotta big fine ,, thats why he changed it ...

[R2HKS]

If you want to ensure that any modification you are thinking about doing is legal or not speak to an engineer 1st before doing the mod. I tend to agree that carbon bonnets would be illegal due to the change in the crumple effect, we all know about pedestrian saftey, a shard of carbon could literally slice you in half at speed.

I know that some fibreglass/metal reinforced 4wd bonnets are RTA approved like FJ40's but I again say speak to an engineer 1st then get him to sign off on it if the mod you are doing is legal.

Cheers