Re: Weight a minute

["Graydon D. Stuckey" <graydon@apollo.kettering.edu>]

On Wed, 8 Apr 1998, MSV96 wrote:

> "A car is able to accelerate faster coming off a corner with weight bias at
> the rear.  For a given amount of acceleration, the cornering force available

This is assuming a rwd vehicle.

> Braking ability is
> also enhanced with a rear weight bias The more weight moved to the rear
> wheels, the more weight that remains there under heavy braking.  And the best
> braking is achieved when the cars weight distribution, under maximum braking
> forces is as close to 50/50 as possible." >>
> 
> Okay, I'll "bite" on this one...(with all due respect Scott). I think the key
> is re-reading this sentance: "under maximum braking forces is as close to

Mike's observation here is correct.    Sinceweight transferrs forwards 
under braking, a static rear weight bias will produce closer to a 50/50 
_under_ braking, so that is why P-cars have incredible accleration and 
stopping.

> 50/50 as possible." Agreed that the front weight bias is not good in the cars
> we behold here (quattros). But, what you cite also implies that "perfect
> 50/50" wmb strives for ain't the best for braking either. Seeing as how if the

Yeah, but 50/50 is a better compromise generally for handling.

> that well made for the money, and that the majority in my area are bought as a
> fashion statement more than they are for enjoying driving them. For me,

Still, they are superb driving machines.

> 87 5kcstq (with the reverse of that crappy weight bias of a 911)

This is one of my beefs with Quattro.  It is great except that it pretty 
much dictates a bad weight bias.  The best packaging for AWD is with the 
engine outside the wheelbase.   There _has_ to be a better way...

> Since this discussion seems to be shifting to that of "perfect weight bias" I
> am curious what the weight bias is for say...a Mercedes CLK-SLR, Ferrari
> 333sp, a McLaren F1 car. I have my doubts any of these are anywhere near 50/50
> (not sure though...just kinda curious now) yet they are each the fastest

I'm not sure anyone knows for sure, but we do know that it is extrememly 
rear biased typically.   Don't get hung up on it for a minute though, 
because there are usually rules at work here.   There are lots of things 
that are done on race cars which would be stupid without the context of 
the rules.

Some good thoughts Mike.

Later,--------------------------- -   -   -   -
Graydon D. Stuckey		 / \ / \ / \ / \
graydon@apollo.kettering.edu	|Mr. Muffler... |
810 733 0255			 \ / \ / \ / \ /
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