Midwest Classic Insurance

Visit our community sponsor

Thanks Thanks:  0
Likes Likes:  0
Results 1 to 7 of 7

Thread: Please help me fix my bump steer...

  1. #1
    Senior Member beeman's Avatar
    Join Date
    Feb 2011
    Location
    Indiana
    Posts
    1,485
    Post Thanks / Like

    Please help me fix my bump steer...

    I have a Mk3.1, SN95 spindles, Fox body power rack. I installed the offset aluminum rack bushings (in orientation recommended on this forum - maybe they should be adjusted), FFR rack arm extenders installed, FFR tubular LCAs, and FFR adjustable UCAs with the SAI relocation kit installed.

    I have driven it for a couple years now, feels great.
    I have tracked the car many times and it feels great to me, but I knew I have a bump steer issue. I had a TransAm Series driver take it out at Autobahn CC and he could feel the bump steer in the corners.

    I can easily see the toe changing when I jack up the front end.

    I bought a high quality bump steer kit to fix it. So I got out my Longacre bump steer gauge last night, I'm changing toe about .200" per 1/2 inch of suspension travel, pretty drastic!

    The tie rod end mounts to the underside of the spindle mount. I installed the new bump steer kit tie rod ends, only to find about the same amount of bump steer as the stock rod ends with no spacers, only to get WORSE as I added spacers. Which leads me to believe that the proper rod end location is at or even above the spindle mount location! But this is a tapered fitting so I'm stuck below the spindle mount unless I modify something... Is there a non-tapered option that is safe?

    Anyone have a (hopefully easy) fix for this?

    Thanks for any help!
    Dave
    MK3.1 2004 Mach 1 donor. ABS, PS, TC.
    GTM #304 LPE 525hp LS3
    2000 C5 Lingenfelter LS1@489hp
    1999 Corvette FRC/Z06 track car

  2. #2
    Senior Member Mike N's Avatar
    Join Date
    Feb 2011
    Location
    Mooresville NC
    Posts
    801
    Post Thanks / Like
    Which way is the rack currently offset? If you offset the rack in the opposite direction does that help?
    Mike............

    FFR2100 - 331 with KB supercharger - T5 - 5 link rear 3.08's and T2 Torsen.

  3. #3
    Not a waxer Jeff Kleiner's Avatar
    Join Date
    Feb 2011
    Location
    Bloomington, Indiana
    Posts
    8,003
    Post Thanks / Like
    You state SN95 spindles but which ones? '94 and '95 model year spindles have the dogleg in the steering arm which greatly improves bump steer geometry in comparison to the straight arms of the 1996 and later versions. You can see the difference here:



    If you have the later version a swap to '94/'95 may be all you need (it will narrow your front track by ~3/8" per side as well).

    Good luck,
    Jeff

  4. #4
    Senior Member beeman's Avatar
    Join Date
    Feb 2011
    Location
    Indiana
    Posts
    1,485
    Post Thanks / Like
    That's a good question, Jeff, I don't remember! I feel like I got the 94/95... I don't recall seeing the dogleg, but I'll check that when I get home. Looks like that 94/95 geometry is what I'm looking for.
    Last edited by beeman; 09-10-2018 at 10:31 AM.
    MK3.1 2004 Mach 1 donor. ABS, PS, TC.
    GTM #304 LPE 525hp LS3
    2000 C5 Lingenfelter LS1@489hp
    1999 Corvette FRC/Z06 track car

  5. #5
    Member JRD56's Avatar
    Join Date
    Oct 2014
    Location
    Olathe, KS
    Posts
    94
    Post Thanks / Like
    I have an MK3 and I originally used spindles from a 2000GT but was not happy with the bump steer I had. I did a pretty detailed analysis and plotted the measurements. I switched to the 94/95 spindles and virtually eliminated all the bump steer.
    Purchased and un-assembled Mk3 in 2016. 5.0, Aluminum heads, Performer RPM Air gap, Quick Fuel 650 carb, BBK headers T5, 3.55 rear solid axle, Koni Shocks, PS with Hydra-boost. Also own two restored vintage Mustangs, two Model A fords, 1941 Chevy truck and several other hot rods.

  6. #6
    Brandon #9196 TexasAviator's Avatar
    Join Date
    May 2016
    Posts
    679
    Post Thanks / Like
    i see you have power rack, what is your camber caster toe settings? I am trying to figure this one out as well. I am not using rack extenders and I have the dog leg 94 95 but no bump steer, just need the settings.

  7. #7
    Senior Member beeman's Avatar
    Join Date
    Feb 2011
    Location
    Indiana
    Posts
    1,485
    Post Thanks / Like
    Jeff, you are correct, I have the straight mount...

    Edit : I found some 94/95s! Thanks for everyone's help!
    Btw I'm at about 7 caster, 1.2 camber, 1/16 toe in.

    Last edited by beeman; 09-11-2018 at 06:39 PM.
    MK3.1 2004 Mach 1 donor. ABS, PS, TC.
    GTM #304 LPE 525hp LS3
    2000 C5 Lingenfelter LS1@489hp
    1999 Corvette FRC/Z06 track car

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Breeze

Visit our community sponsor