Andrew, Needless to say, he runs 14" wheels and we are usually pretty close when it comes down to lap times etc. Also, I think nearly everyone else runs 14" wheels, but that doesn't mean they are all right!
He has a number of points - some of them I find difficult to swallow, others have some credence. 1) Run 14" wheels and let the torque (I run an FJ - which is very torquey) pull the car out of the corner with the 14" wheels. - my argument is that I could change diff ratios if that is what I wanted to achieve. 2) 14" rim will have a larger outer diameter, therefore more rubber - which in turn means the tyres will not get as hot because you are using more rubber to do the same task. (I think he's clutching at straws here!) 3) 195/60 will have a smaller side wall than a 205/60 - which is true. But.....the 205 is only a 13" when the 195 is a 14" therefore won't they pretty much cancel each other out or at least the contact patch of the 205 must be worth something here? 4) The whole bigger brakes argument - my opinion there is that I am already out braking other people so why would I need bigger brakes? I am running four spots with a 260mm vented disk up front, with disks in the rear also - stops pretty good! He had some others also, but they were a bit left of field and/or he didn't have a good explanation as to why. I'm all for taking advise, hence I posted this message, but I don't like to change things simply on someone's word - I like to know why, and so far, no one has managed to show me why 14" wheels will give me a better package than what I already have, or will bring my lap times down any further. Cheers, Mark. ----- Original Message ----- From: "Andrew Greenbury" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Thursday, April 04, 2002 4:49 PM Subject: Re: What size wheels are best? > Hey Mark, > > No worries - what is the view of the guy you have been having a > long running discussion with?? > > > > Cheers Andrew, I appreciate the feedback. > > > > So far nothing has been said to make me think that 14's are the way to go. > > This justifies what I have been telling myself for ages, just needed some > > other opinions to confirm it. > > > > Thanks to all who have replied. > > > > Mark. > > > > P.S. If any one thinks that 14's would be the way to go, I would still like > > to hear why. > > ----- Original Message ----- > > From: "Andrew Greenbury" <[EMAIL PROTECTED]> > > To: <[EMAIL PROTECTED]> > > Sent: Thursday, April 04, 2002 4:20 PM > > Subject: Re: What size wheels are best? > > > > > > > Hi Mark, > > > > > > yeah I agree with Errol for the same kind of reasons esp in your > > > racing context. Your rubber choice is greater, and you already have > > > the 13s. > > > > > > Rotational inertia is proportional to mass*radius^2, so the > > > distribution of mass around the wheel has a greater effect than the > > > overall weight itself. The lower the inertia the less torque/force > > > required to accelerate (and brake) the wheel. Also the wheel will > > > accelerate/brake faster. > > > > > > Because of this as Errol said, bigger rims also require bigger > > > brakes, but bigger brakes add more rotating mass etc etc. > > > Generally, larger diameter tyres weight more too, and this mass > > > has the largest radius. > > > > > > >From a handling point of view, the 13s give you a wider contact > > > patch and a larger grip envelope. Because you have to keep the 60 > > > profile, the difference in sidewall thickness should be similar as > > > Ben mentioned, so you would expect the cornering stiffness of both > > > sizes to be similar. The perception of the lower the profile the better > > > the performance isnt always the case - what size tyres do F1 use? > > > > > > Andrew > > > > > > > Ok Errol, > > > > > > > > I currently have the 13" wheels. Brake wise I am running a set of > > > > four piston sumitomo callipers. These callipers are apparently > > > > works Nissan Callipers from an older model Japanese 300ZX. The > > > > Callipers are not alloy, and are quite weighty. The disc is of > > > > unknown origin (came with the car) but is 260mm diameter and is > > > > vented. > > > > > > > > This setup works very well in it's current configuration. If > > > > however, I was to go to 14" wheels, what size rotor and which > > > > Callipers would you recommend? > > > > > > > > Also, from a handling point of view, would the 14" wheels provide > > > > better handling? Keeping in mind I still have to run the 60 series > > > > tyre, and would be forced to run a 195 as opposed to the 205/60/13 > > > > I am currently running? > > > > > > > > What do you think? > > > > > > > > Mark. > > > > ----- Original Message ----- > > > > From: E Smith > > > > To: [EMAIL PROTECTED] > > > > Sent: Thursday, April 04, 2002 11:43 AM > > > > Subject: RE: What size wheels are best? > > > > > > > > > > > > Its also a matter of moments and braking toque. Assuming the > > > > same caliper and applied pedal force in every condition: - > > > > > > > > The larger the rotational diameter of the wheel/tyre, the disc > > > > required must be proportionally larger diameter to maintain the > > > > same braking effort. > > > > > > > > > > > > > > > > The classic wheel size example is the "EVO mock up" lancer with > > > > the 9" discs inside 18" wheels and they wonder why they will not > > > > stop. I have a feeling that a lot of accidents recently have been > > > > caused by these mismatches of tyre - wheel / brake - caliper > > > > combinations. > > > > > > > > > > > > > > > > I personally like 13 X 7" rims as the range of rubber is better > > > > for this size wheel, from treaded competition tyres to slicks. > > > > They are also usually lighter. The next size up is 15" rims to > > > > get a good selection of rubber. As the diameter goes up though so > > > > does the price. > > > > > > > > > > > > > > > > Cheers > > > > > > > > Feral Errol > > > > > > > > > > > > > > > > -----Original Message----- > > > > From: [EMAIL PROTECTED] > > [mailto:[EMAIL PROTECTED]]On Behalf Of Mark Alford > > > > Sent: Thursday, 4 April 2002 9:26 AM > > > > To: Ozdat discussion list > > > > Subject: What size wheels are best? > > > > > > > > > > > > > > > > Hey listers, > > > > > > > > > > > > > > > > I have been having a long running discussion with a guy I race with > > regarding wheel sizes, and what size wheel is best to run. I thought I might > > throw the question open to the list and see what thoughts are out there. > > > > > > > > > > > > > > > > What I would like to know is - What size (diameter) wheel is > > > > best to run? the choice is between two sizes 13" and 14" (both > > > > with 7" width). Something else that also needs consideration is > > > > the tyre that I must run. If I run the 13" I can use a 205/60. If > > > > I run the 14" I must run a 195/60. (Everyone must use a 60 series > > > > tyre) > > > > > > > > > > > > > > > > So who out there has some thoughts on which combination I should run? > > I would also like to know the reasons behind peoples thoughts. > > > > > > > > > > > > > > > > I look forward to the feedback. > > > > > > > > > > > > > > > > Mark. > > > > > > > > > > > > > > > > > > > --membersozdat------------------------------------------------------- > > > > OZDAT Mailing List Please Note:- > > > > Send (un)subscribe requests to [EMAIL PROTECTED] > > > > Send submissions to [EMAIL PROTECTED] > > > > No unauthorised redistribution of this email > > > > http://www.ozdat.com/ozdatonline/index.htm > > > > http://www.ozdat.com/ozdatonline/listindex.html > > > > http://www.mail-archive.com/[email protected]/ > > > --------------------------------------------------------------------- > > > --membersozdat------------------------------------------------------- > > > > OZDAT Mailing List Please Note:- > > > > Send (un)subscribe requests to [EMAIL PROTECTED] > > > > Send submissions to [EMAIL PROTECTED] > > > > No unauthorised redistribution of this email > > > > http://www.ozdat.com/ozdatonline/index.htm > > > > http://www.ozdat.com/ozdatonline/listindex.html > > > > http://www.mail-archive.com/[email protected]/ > > > --------------------------------------------------------------------- > > > > > > > > > > > > > > > > > > --membersozdat------------------------------------------------------- OZDAT Mailing List Please Note:- Send (un)subscribe requests to [EMAIL PROTECTED] Send submissions to [EMAIL PROTECTED] No unauthorised redistribution of this email http://www.ozdat.com/ozdatonline/index.htm http://www.ozdat.com/ozdatonline/listindex.html http://www.mail-archive.com/[email protected]/ ---------------------------------------------------------------------
