SUPPORT OUR SPONSOR

Go Back   Club Cobra > Club Cobra Tech Areas > Shop Talk

Welcome to Club Cobra!  The World's largest non biased Shelby Cobra related site!

  •  » Representation from nearly all Cobra/Daytona/GT40 manufacturers
  •  » Help from all over the world for your questions
  •  » Build logs for you and all members
  •  » Blogs
  •  » Image Gallery
  •  » Many thousands of members and nearly 1 million posts! 

YES! I want to register an account for free right now!  p.s.: For registered members this ad will NOT show

MMG Superformance
Nevada Classics
Keith Craft Racing
Main Menu
Nevada Classics
Nevada Classics
MMG Superformance
MMG Superformance
Advertise at CC
Banner Ad Rates
MMG Superformance
MMG Superformance
August 2022
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      
  #61 (permalink)  
Old 05-29-2004, 09:08 PM
computerworks's Avatar
Senior Club Cobra Member
Visit my Photo Gallery
Lifetime Contributor
 
Join Date: Mar 2001
Location: Northport, NY
Cobra Make, Engine: Kirkham, KMP178 / '66 GT350H, 4-speed
Posts: 10,362
Not Ranked     
Default

Guys... quit the sniping.
Please.
Keep this on topic.

Ron
ClubCobra Moderator
Reply With Quote
Sponsored Links
Sponsored Links
  #62 (permalink)  
Old 05-29-2004, 09:10 PM
G.R.'s Avatar
Senior Club Cobra Member
Visit my Photo Gallery

 
Join Date: Jul 2001
Location: Evans, CO
Cobra Make, Engine: NAF 289 FIA, 347 stroker with Weber 48's, building a '48 Anglia gasser, driving a '55 Chevy resto-rod
Posts: 3,119
Send a message via Yahoo to G.R.
Not Ranked     
Default

Sorry, Ron
__________________
"Breathe in... Breathe out... then move on with life. Lifes too short to sweat the small stuff"
Reply With Quote
  #63 (permalink)  
Old 05-30-2004, 12:01 AM
Dominik's Avatar
CC Member
Visit my Photo Gallery

 
Join Date: Jun 2000
Location: Cape Town, South Africa/Mainz, Germany,
Posts: 1,499
Not Ranked     
Default a-arm bushes

I spoke to my buddy in chassis engineering in 1999 when I had the same problem with my Miata.

It appears that a lot of manufacturers battle with this.
He mentioned using a different kind of a-arm bush to reduce the effect.

I can't remember the details and also lost contact since I moved.

What type of suspension bushes do you run? Did anybody try a different version?

Isn't vibration also related to diameter (in addition to speed)?
So smaller tires or bigger should vibrate at different speeds.

This will not really help to find out, but would be intersting to know anyway.
Pity that the US speed limit falls in that range...

Dominik, Cape Town
__________________
If I don't respond anymore, that's because I can't log in...
Reply With Quote
  #64 (permalink)  
Old 09-13-2004, 05:00 AM
CC Member
Visit my Photo Gallery

 
Join Date: Jul 2003
Location: NJ Shore, NJ
Cobra Make, Engine: Lone Star 350/385 hp Chev "Fast Burn"
Posts: 38
Not Ranked     
Default Shimmy

My Lonestar shimmys from 60-70 (not as bad during acceleration)
I just had the car aligned and found both caster and camber to be way off... so its possible that the Goodyear Eagle GT II's on Centerline rims could have worn enough to be a problem.. I'll have the run out and balancing checked and then spring for new tires.
Reply With Quote
  #65 (permalink)  
Old 09-14-2004, 08:34 AM
FFR428's Avatar
CC Member
Visit my Photo Gallery

 
Join Date: Oct 2002
Location: Fairfield, CT
Cobra Make, Engine: HM-2027 / 427 SO
Posts: 801
Not Ranked     
Default

FWIW some of the FFR guy's have this problem also. The BFG TA's have been the culprit and others badly balanced rims from the manufactuer. Some have installed Jeep steering stabilizers to both sides to eliminate this problem. Mounting brackets are needed to be fabbed and welded to the frame. You can see it at the FFcobra website under the FAQ's section. Click on steering vibration. G.
Reply With Quote
  #66 (permalink)  
Old 10-11-2004, 05:44 AM
CC Member
Visit my Photo Gallery

 
Join Date: Jul 2003
Location: NJ Shore, NJ
Cobra Make, Engine: Lone Star 350/385 hp Chev "Fast Burn"
Posts: 38
Not Ranked     
Default

For what it's worth... A new set of Goodyears solved my problem..
However.. I blew the engine while testing them out. New 350 Chev. "Fastburn" crate motor has been installed ... life is good.
Reply With Quote
  #67 (permalink)  
Old 12-18-2004, 02:47 PM
Rwillia4's Avatar
CC Member
Visit my Photo Gallery

 
Join Date: Aug 2003
Location: San Diego, CA
Cobra Make, Engine: BDR #455, KC427W, TWM-FI
Posts: 727
Not Ranked     
Default Hub or Lug Centric Wheels?

I know this may sound simple but shimming has caused me problems in the past. Rim manufactures make rims either hub centric (the big circle in the middle it the dead center but the lugs can be off) or lug centric where the dead center of the lugs is the center of the tire and is totally independent of the hub (look at my picture, I used 4 lugs cus I can't draw!). The problem is when you have the wheel balanced on a machine that is hub centric but have a lug centric wheel or vice-versa. The wheel will repeatedly be balanced on the machine but when you put it on the car it shimmies. This has been a problem for many Toyota truck owners (that use a stock lug centric wheel) when they go to a standard tire seller and have their wheel balanced on the standard hub centric machines that MOST of the tire seller’s use. The fix is to know how you wheel is manufactured and make sure you go to a tire place that can balance the type you have, probably a lug centric. He will need to use a lug centric adapter when balancing your wheels. I went to a few places that said “no problem, we can do that” to have the car shimmy as drive away. I have learned to take my truck to a Toyota dealer that charger $2.00 more and does it right the first time. When putting a lug centric wheel on you need to make sure to snug ALL the lugs in a "skip a lug" pattern before making them tight. This will center the wheel properly
Attached Images
 
Reply With Quote
  #68 (permalink)  
Old 12-19-2004, 05:21 AM
Bob In Ct's Avatar
Senior Club Cobra Member
Visit my Photo Gallery

 
Join Date: Mar 2001
Location: Southern Connecticut, CT
Cobra Make, Engine: SPF - 351W, 944 non-turbo
Posts: 2,105
Not Ranked     
Default

Rwillia4:
Your post may be the on money for many cars. Keep in mind however, that many Cobra owners with non-lug wheels have the problem. I reduced the vibration in my SPF by having the tires "trued". www.amermac.com
Bob

Last edited by Bob In Ct; 12-19-2004 at 05:27 AM..
Reply With Quote
  #69 (permalink)  
Old 12-19-2004, 06:34 AM
trularin's Avatar
Member of the north
Visit my Photo Gallery

 
Join Date: May 2003
Cobra Make, Engine: A Cobra
Posts: 11,202
Not Ranked     
Default

I actually checked my wheels before mounting by "rolling" them on my lathe bed and put a dial indicator in the spindle chuck.

The centers were about .002 out. I can not turn the wheels ( saddle size ), so I live with it. But, I do not get a shake.

__________________
I'm a writer, feed the artist and buy a book.
Reply With Quote
  #70 (permalink)  
Old 12-19-2004, 07:20 AM
Don Don is offline
Senior Club Cobra Member
Visit my Photo Gallery

 
Join Date: Aug 1999
Location: Ellington, CT
Cobra Make, Engine: Classic Roadster 351W, T5, Red & White
Posts: 3,476
Not Ranked     
Default

Bob, I have never experienced the shake problem. The Classic Roadster Cobra was built by Don Scott and has a GM tilt steering column.

The tires are TA radial with 245 X 60 X 15 in front, Compomotive HB 8" , 4" backspace , and 275 X 60 X 15 in rear, Compomotive HB 9", 4.6 " backspace.

The tires were rebalanced when I moved the mounting of the tire's white print to the inside, no reason other than personal preference. The alignment is the same as when Don built the Cobra.

HAPPY HOLIDAYS

Regards

Don
__________________
2014 Porsche Cayman S, 2014 M-B CLA 45 AMG, 1940 Chev V-8
Unkown:"Their sweet lines all but take my breath away, and I desire them as much for their beauty as for their use "
Reply With Quote
  #71 (permalink)  
Old 12-19-2004, 08:39 AM
Bob In Ct's Avatar
Senior Club Cobra Member
Visit my Photo Gallery

 
Join Date: Mar 2001
Location: Southern Connecticut, CT
Cobra Make, Engine: SPF - 351W, 944 non-turbo
Posts: 2,105
Not Ranked     
Default

Don:
Can I assume your steering column has a "rag joint"? If so, the vibration is eliminated before it gets to the steering wheel.

Bob
Reply With Quote
  #72 (permalink)  
Old 12-19-2004, 10:49 AM
CC Member
Visit my Photo Gallery

 
Join Date: Jun 2000
Location: Redding,Ct., ct
Cobra Make, Engine: Unique S/C with 428
Posts: 56
Not Ranked     
Default

Bob,

Where in CT did you find the Chevy dealer with the tire machine you spoke of ? Did you have your tires trued up at Major Tire in Bridgeport ? For the record 1993 Unique, MG front end , Compomotive HB wheels and B.F. Goodrich tires. It starts to dance around 60mph.

Pete Wolff
Reply With Quote
  #73 (permalink)  
Old 12-19-2004, 02:55 PM
Bob In Ct's Avatar
Senior Club Cobra Member
Visit my Photo Gallery

 
Join Date: Mar 2001
Location: Southern Connecticut, CT
Cobra Make, Engine: SPF - 351W, 944 non-turbo
Posts: 2,105
Not Ranked     
Default

Major Tire, dealt with Dave for truing. Hunter machine at Chevy dealer in Milford on Route 1. Hunter machine is overrated (in my opinion).

Bob
Reply With Quote
  #74 (permalink)  
Old 12-19-2004, 03:33 PM
CC Member
Visit my Photo Gallery

 
Join Date: Jun 2000
Location: Redding,Ct., ct
Cobra Make, Engine: Unique S/C with 428
Posts: 56
Not Ranked     
Default

Bob, am I correct in assuming that the tire "truing" didn't correct your steering wheel shake ? I am planning on having mine done in the spring......worth it or not?
Reply With Quote
  #75 (permalink)  
Old 12-19-2004, 05:39 PM
Bob In Ct's Avatar
Senior Club Cobra Member
Visit my Photo Gallery

 
Join Date: Mar 2001
Location: Southern Connecticut, CT
Cobra Make, Engine: SPF - 351W, 944 non-turbo
Posts: 2,105
Not Ranked     
Default

Don:
I stand corrected! I took my tires and wheels to Major Racing Traction in Bridgeport. They're at 20 Union Avenue, 203-367-7223, talk to Dave.

Pete:
It did not eliminate the shake but it significantly reduced it. Others I know say it all but eliminated it. A rag joint in the steering column would help a lot.

Bob
Reply With Quote
  #76 (permalink)  
Old 12-20-2004, 10:59 AM
Don Don is offline
Senior Club Cobra Member
Visit my Photo Gallery

 
Join Date: Aug 1999
Location: Ellington, CT
Cobra Make, Engine: Classic Roadster 351W, T5, Red & White
Posts: 3,476
Not Ranked     
Default

Bob:

Don Scott built my CR, no rag joint, his reply:

Don, I don't use a rag joint. I use a solid shaft with u-joints at each end to connect to the GM column and rack. The rag joint is usually a leather or rubber cushion between the rack and the steering shaft. It does help eliminate vibrations and steering wheel shake. Flaming river sells a joint with a vibration dampner built in. I have found that most of the time the problem is in the wheel balance and the alignment.
Don
__________________
2014 Porsche Cayman S, 2014 M-B CLA 45 AMG, 1940 Chev V-8
Unkown:"Their sweet lines all but take my breath away, and I desire them as much for their beauty as for their use "
Reply With Quote
  #77 (permalink)  
Old 12-20-2004, 06:36 PM
Senior Club Cobra Member
Visit my Photo Gallery

 
Join Date: Oct 2004
Location: Roanoke, Tx
Cobra Make, Engine: 2002 Lone Star Classics LS427, 428 CJ engine stroked to 464, 580hp/590tq at flywheel
Posts: 557
Not Ranked     
Default

As a new Cobra owner I had noticed the steering wheel shake, buit it did not feel like an out of balance thing. I was running Bridgestone Potenza 245/45/17 front and 275/40/17 rears. I wanted to get a little more rubber on the rear so changed the Bridgestone to the Goodyear IIs 245/45/17 front and 315/35/17 rear. Discount Tire did what they called a performance tune on the tires/wheels for an additional $10/tire and it is now smooth as glass with no wheel shake. I am running solid steering u joint. I don't know if the old tires were out, but they did not have to do anything with the alignment. If they are in your area you might give them a try.
Reply With Quote
Reply


Thread Tools
Display Modes

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 On
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -7. The time now is 12:31 AM.


Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2022, 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