Club Cobra Keith Craft Motorsports  

Go Back   Club Cobra > General Discussion > All Racing Talk

Keith Craft Racing
Nevada Classics
Main Menu
Module Jump:
Nevada Classics
Nevada Classics
MMG Superformance
Keith Craft Racing
Advertise at CC
Banner Ad Rates
Keith Craft Racing
Keith Craft Racing
January 2026
S M T W T F S
        1 2 3
4 5 6 7 8 9 10
11 12 13 14 15 16 17
18 19 20 21 22 23 24
25 26 27 28 29 30 31

Kirkham Motorsports

Like Tree14Likes

 
 
LinkBack Thread Tools Display Modes
Prev Previous Post   Next Post Next
  #19 (permalink)  
Old 11-14-2018, 08:57 PM
Richard Hudgins's Avatar
Senior Club Cobra Member
Visit my Photo Gallery

 
Join Date: Jun 1999
Location: Fallbrook, CA USA, CA
Cobra Make, Engine: Porsche 928 S4
Posts: 739
Not Ranked     
Default

Quote:
Originally Posted by xlr8tr View Post
Curious Richard, would the 295 and 355 kuhmo's fit on the JBL? Section widths of 12.1 and 14.2" respectively. One would think with current state of the art tires the numbers would be even better, assuming you could keep oil in the engine
The Comp chassis would accept the section widths that you quote as there is room for the increased wheel width while maintaining the same outside dimensions and therefore the motion ratios would still be correct. (Just add the required 2 inches to the backspacing)

More contact patch does indeed equal more grip if the suspension geometry is correct for the tyre construction. I am not familiar with the Kunmo sidewall design so I cannot give you a honest opinion on how they might work on the JBL.

The camber curves were designed for the Hoosier radials of the time and by good fortune the Michelin Pilots of the era were very close on the sidewall angle deflection numbers. The tyre pressures required were quite different between the two brands because the Michelin sidewalls were much stiffer than the Hoosiers.

And to Mark's comment "The up and down movement of the rockers is very fast even on a seemingly smooth road".

He nailed the reason for the front end rocker design there. The motion ratio is about 1.2-1 on the rockers. This was to increase the damper shaft motion and speed as very short shaft displacements are extremely difficult to valve for and control.

There are other reasons for this motion ratio as well that have to do with creating a rising spring rate curve that worked with the very high moment around the design roll axis.

This same philosophy was finally applied to the rear of the later cars with the introduction of the pull rod design.

Since Mark has examples of both chassis possibly he could comment on the differences that he feels in the dynamics of the two designs.

The pull rod car should give a much more stable transfer of weight and rotation about the roll axis. Transition from one direction to another should be quicker and more predicable as well.

Of course things being as they are when doing vehicle design, the best laid plans of Mice and Men etc...................
__________________
Best regards,

Richard Hudgins
Reply With Quote
 


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -7. The time now is 02:50 AM.


Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2026, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
The representations expressed are the representations and opinions of the clubcobra.com forum members and do not necessarily reflect the opinions and viewpoints of the site owners, moderators, Shelby American, any other replica manufacturer, Ford Motor Company. This website has been planned and developed by clubcobra.com and its forum members and should not be construed as being endorsed by Ford Motor Company, or Shelby American or any other manufacturer unless expressly noted by that entity. "Cobra" and the Cobra logo are registered trademarks for Ford Motor Co., Inc. clubcobra.com forum members agree not to post any copyrighted material unless the copyrighted material is owned by you. Although we do not and cannot review the messages posted and are not responsible for the content of any of these messages, we reserve the right to delete any message for any reason whatsoever. You remain solely responsible for the content of your messages, and you agree to indemnify and hold us harmless with respect to any claim based upon transmission of your message(s). Thank you for visiting clubcobra.com. For full policy documentation refer to the following link: CC Policy
Links monetized by VigLink