Traction on 20's?

Discussion in 'Wheels & Tires' started by Hellspawn, Dec 8, 2013.

  1. Norm Peterson

    Norm Peterson corner barstool sitter

    First Name:
    Norm
    Vehicle(s):
    '08 GT #85, '10 LGT, '01 20AE
    Joined:
    Jul 22, 2013
    Location:
    On a corner barstool not too far from I-95
    Posts:
    6,227
    Likes Received:
    2,469
    0   0   0
    A tenth is a tenth, not the whole second claimed. What I'm saying is the ability of short sidewall 19's to launch could possibly be that much poorer than taller sidewall 16's of the same OD. Maybe this hurts some people more than it does others.

    Incidentally, the V6 and 4.6/GT rear brakes are both 11.8" rotors, meaning that nothing special needed to be done to run the 16" tires at least in the rear for acceleration purposes. Launch bite, remember, which does not depend on front tire size (yeah, it would be nice if we knew whether a single set of front tires was used for every test).


    I don't take anybody's mpg numbers to anything finer than whole mpg's, so I agree with you that at least that part cannot be as precise as implied.


    So let's see if he comes back in to provide further description.


    Let me remind you how I phrased it. Emphasized.
    There is a lot we don't know yet. Too much. What I'm mainly interested for the original purpose of this thread is limited to the difference in rotational inertia (which is small and can be estimated pretty closely) and in launch bite (which is unknown and tire dependent).

    Beyond that, some peoples' launch technique almost certainly suffer more than others' when the tires won't take a brutal launch. While you probably can't see with the naked eye any sidewall wrinkling to absorb shock in any of the street tires Build'em used, the effect is still there and will still give the tall sidewall tire an advantage. I can't put a number on this, unfortunately.


    Norm
     
  2. scottpe

    scottpe Well-Known Member

    Vehicle(s):
    2012 GT 6MT w/ Brembos
    Joined:
    Dec 8, 2013
    Location:
    DFW, TX
    Posts:
    1,357
    Likes Received:
    3
    0   0   0
    I want to know what equipment and testing methodologies were used and how you possibly could have measured to the accuracy of 1/100th of a mile for MPG or a fraction of a foot for the stopping distances?

    And saying that you changed ALL acceleration categories by a full second simply by going from 16" wheels to 19" sounds REALLY far fetched (I'm being kind here). In my experience, the average E/T improvement when going from street radials to SLICKS on a street car, irrespective of wheel size, is 1 second or less in the quarter mile. An OEM 2006 GT would probably be closer to .5 seconds. So you're trying to tell us that you got a better improvement by simply going from a 19" to a 16" street tire (internal diameter) than one would get going to full slicks?? Are you sure you didn't mean .1 seconds??

    And your claim that wider tires do not help straight line grip/traction is even more dumbfounding. If that's the case, when I get my 2015 Mustang, I'm pulling the 275s off in the rear and putting 195s on there when I go to the strip!

    I'm not a scientist, but I have drag raced and watched plenty of them to know that something sounds really off about your claims...
     
  3. MPH

    MPH Well-Known Member

    Vehicle(s):
    2018 Mustang GT
    Joined:
    Mar 27, 2013
    Location:
    AR
    Posts:
    115
    Likes Received:
    0
    0   0   0
    [​IMG]
     
Loading...

Share This Page