I don't have a dog in this fight...at least not directly, but I can respond to a few of Chris' points here.Originally Posted by Camadella
When the rule was written in 1985 (...it went into effect on 1 Jan 86) the average wholesale price of carbon fiber was about $65 a pound (Source), or about 50 times that of fiberglass, so Chris' main point above is technically correct.
That said, by 1985 carbon fiber was already welcome in the even lower-spec Formula Vee class, so the argument that cf posed some class-killing quantum jump in cost is tenuous at best. Nevertheless, the Adhoc Committee recommended prohibiting cf and kevlar. FF participation was in free fall by '85 anyway, due to rapidly escalating costs and competition from Spec Renault, so presumably the Committee felt the prohibition was justified. In any case, the recommendation was passed.
Not quite. Cf is very much cheaper today than 25 years ago (current wholesale price is about $8/lb), but that's still nearly twice the price of fiberglass. S-glass runs about $15/yd for 6-oz, versus about $25/yd for 6-oz cf. E-glass is about half the price of s-glass, but is not as good in motorsports applications as s-glass because it is not as stiff as s-glass.Now, it's 2010. Carbon fiber is cheap. As cheap as fiberglass.
Where cf comes into the fore is that for a given piece (say, an engine cover), one can typically delete one layer and still have the same stiffness as with a glass piece. That directly translates to lower cost (and slightly lighter weight).
In my considerable experience a typical FF/FC engine cover takes about 2 yds of cloth per layer and is laid up from three layers of fg, that's 6 yds x $15 for the s-glass, plus 6 x 6 oz of resin at $1/oz, or $126 in materials. In cf that's 4 x $25 for cloth + 4 x 6oz resin = $124 in materials, plus the labor saved by not having to wet out that third layer. So, compared to s-glass, carbon fiber is cheaper by the difference in labor. The numbers for e-glass are 6 yds of cloth at $8/yd = $48 + $36 = $84 in materials, or about $40 cheaper than the materials in cf, so the net cost is about the same when you factor in the labor costs.
Clearly, in terms of the finished product cost, cf is now days no more expensive than fiberglass...unless you pay your labor nothing. The argument that cf itself raises the cost bar in FF is simply not true unless you are making your own bodywork, and then ONLY if you use the absolutely cheapest boat-glass.
PS - The prices I quote for materials reflect my as-delivered cost in whole dollars for 100 yd rolls of cloth and barrels of resin we use at Dauntless. YMMV.
. I've had to reject more then one car that did not meet the rules... and "blue printing is allowed 
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. Ballast is free in material and location. Correct location can make a winner, incorrect a loser.... also depends on the track used. Gee, kind of like real race cars isn't it??
