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Old 04-06-2010, 06:51 PM
DMXF DMXF is offline
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Default Dynamics

Quote:
Originally Posted by john chesnut View Post
I relayed my experience to illustrate the dynamics of the longer wheelbase, wider track, better balance, and lower center of gravity of my T bucket to the Cobra dimensions. Both cars have the exact same drivetrain and suspension.
John, no one will dispute that a wider track will enhance handling and longer wheelbase provide more stability, as stand-alone variables, ie; yes, all else unchanged (incl weight, roll centers, etc), by increasing track the lap times will definitely go down. But that is not really what we're dealing with here.

First of all, by moving the suspension out on your cars, you are no doubt altering relationships of roll center to cg, ackerman, etc, which are probably more optimal at the Corvette track width they were designed for.

More pertinent to a comparison of the Cobra to a Vette, however, is that the Vette appears to be a much bigger, taller and obviously heavier car.




The handling characteristics of a Vette should remain constant if you scaled the car down to 75% of full size, 50% or 5%. So from a parametric standpoint, it looks like a Cobra is probably close to being a scaled down version of a Corvette (track narrower, length proportionately shorter, weight less than proportionately lower, etc). With that scaled relationship of all parameters, you can't accurately say the narrower track, etc of a Cobra would alone make it handle inferior to a Vette. Note that a Cobra's track and wheelbase are almost the same as a Mazda Miata and a lightweight spec Cobra with aluminum FE engine, etc is essentially the same weight as the Miata (around 2200lb). I recall a Miata was recently tested against a number of modern supercars like the Corvette (ZR1?) on some race track and written up in one of the big car magazines... it's lap times were middle of the pack, with only around 1/2 the horsepower of the other cars along with narrower tires, and I believe the Mazda only has a rinky-dink McPherson strut suspension (correct me if wrong).

Note that I am not saying that going to a wider track on a Cobra wouldn't improve its handling, just that a narrower track on a lighter, smaller car like a Cobra doesn't mean it will have worse handling than the Vette. Yes, there are other attributes that could be hurting the Cobra, like if the cg to roll center relationship were worse, but that is a separate issue. I believe one of the things that messes up handling on alot of Cobras is running too small of a diameter and width front tire (ref Kirkham thread which linked to an article about Nissan GTR handling).

Last edited by DMXF; 04-06-2010 at 06:59 PM..
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