[chrisguyw]

A lot has changed over the years in our hobby..........years ago most raced on large commercial type tracks, with long straights and wide radius corners, with cars with much grippier tyres (sponge/traction additives), and much more powerful motors. In this environment, nothing beats a brass/wire/steel chassis, as the cornering speeds/torsional chassis loads require (still do today) a much stiffer motor box, and a stiffer (both longitudinally and torsionally) chassis. 

The type of racing most commonly done today  (home/club,...plastic/wood tracks) utilizes smaller/tighter tracks with relatively less grippy tyres and far less motor torque, so a softer flexing chassis and a flimsier motor box (plastic chassis) suffice with the  lower cornering loads and motor power used most frequently today.  (A stiff motor box area is still very beneficial to todays plastic cars, but that is for another thread). While most current plastic chassis' can certainly benefit from a few modifications, they largely do a very good job. 

So, with that said, a very well designed and built brass/wire/steel car in todays hobby can compete and out perform a plastic one, but, the margins are very very  small, and while I do encourage everyone to try making their own chassis, please do not despair if your first few efforts do not outperform the plastic stuff on your shelf. Again, it does take a well designed/built metal chassis to rival todays plastic offerings

I have seen many high tech chassis designs that were not particularly well executed being out performed by some simply designed but well built chassis.

In any chassis the two most critical elements are that it be flat (both axles absolutely horizontal) and square (both axles absolutely parallel).....all the rest, weight/weight balance, torsional flex, guide lead, etc. are important, but without being flat and square, they just don't matter.

Cheers
Chris Walker