To CF or not to CF...

[tuffAC]

Hi all. Came across this thread in another forum:

"the concept is simple:anything that is supported by the vehicle's springs is considered sprung weight. If you really care to become knowledgeable in the subject area, read all of the "...to win" books by Carroll Smith. Also, I dare you to find a CF hood that would alone shave 1 second off of a quarter mile time. If you were really informed in the subject area you would find that 1 Second is a ton in drag racing and the means to achieve that are not as simple as bolting on a CF hood"

There are a few statements which have got me thinking. It makes logical sense that decreasing weight on any given car will obviously improve performance times. However a counter statement was made in regards to honda cars - being front wheel drive decreasing weight "you're essentially decreasing the weight over the wheels that propel the car... thus decreasing the traction, especially on wet roads".

There was also a claim in there that replacing a OEM bonnet will decrease 1/4 mile times by 1 second.

My perceptions on carbon fibre bonnets has always been that its mainly for cosmetic reasons. I dont think changing to a carbon fibre bonnet will improve times. Also given the fact that its a daily driven car with all electricals and not one which has been stripped and race prepped, decreasing only a bonnet wont change much.

While the cool factor maybe there with carbon fibre bolt-ons, i dont see any real justifications. I may be contradicting myself for saying this, as i admit i am quite keen on CF bonnets and dont get me wrong i believe they look hot. But does one actually believe a car will be that much faster with CF??

Has anyone changed their bonnets to CF - if so has your performance enhanced???.....

physical rather than psychological please!

For now cheers to you all, :wave:

__________________

[razaman]

Some of the logic doesn't make any sense to me.

I don't think anyone would expect to save 1 second from just replacing the bonnet. A CF bonnet however could save upwards of 20kg.

However it doesn't make any sense that taking weight away would make you slower, then increasing weight would make you faster. Otherwise I could make my car go faster by putting 6 fat bastards in my car - but everytime I do I go slower.

An accord with the same hp as a civic will lose - because the civic is lighter.

If you want to save alot of time then some serious weight reductions are required.

CF Bonnet
Remove AC
Remove Carpet and sound deadening
Remove spare tyre and tools
Remove sounds
Lightweight wheels
Remove spare seats.
etc

All in my opinion.

Raz

[aaronng]

It's not only decreasing the weight over the wheels, but changing the distribution of the weight between the front and rear. If you have 2 FWD cars, both with the same weight. THe first has a weight distribution of 60/40, while the 2nd has been rebalanced to give 70/30. The 2nd will have more traction because a higher proportion of the weight is over the wheels.

The 2nd thing, is that a lighter car will have less inertia to overcome, so you will also spin your wheels less.

[EuroAccord13]

Hey TuffAC!!! :D

This will be better answered in the Technical Section for ya :)

Moving it :)

CHEERS

[sivic]

of course a carbon bonnet wont take a second off the 1/4 but when it comes to weight reduction it all adds up.
a CF bonnet wont save you upwards of 20kg. an oem eg bonnet only weighs ~ 15kg. most eg CF bonnets weigh ~ 7kg so 8kg weight off. (i measured this myself)
add this saving to the other stuff you take out and it all makes a difference

but CF bonnet alone - i didnt feel a performance diff. if anything were to improve from this mod it would be steering with less weight over the front = less understeering

[joonix]

Please note that none of the currently offered CF bonnets meet ADRs, and are consequently defectable. If you hit a pedestrain you can really hurt them, and you will be ****ed over in court.

CF bonnets are purely for the track or stip.

Whilst reducing the weight over the front wheels can lead to traction problems, It can be corrected through suspension modification and tyre choice. If you are serious about drag racing, you should invest in a set of adjustable suspension components, and semi-slicks or ideally slicks to bolt on at the track.

I would adress these issues, as well as removing unessicary components from the vehicle before purchasing a CF bonnet. Remocing your airconditioning, back seat, spare tyre, sound deadening etc is free :)