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Thread: What's the difference?

  1. #1
    Junior Member slimcobra's Avatar
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    What's the difference?

    What are the differences between a gen 1 and a gen 2? Does the first gen kit come with everything that the 2nd gen does? Thanks for any info you can share.

  2. #2
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    Five differences with the body:
    1. Reshaped radiator vents on hood - went from large open area with mesh to cover on Gen 1 to smaller louvered area on Gen 2.
    2. Headlight buckets integral to the hood on Gen 2; need to be attached to hood on Gen 1.
    3. Doors changed slightly - Gen 1 has triangle portion of A-pillar on door, Gen 2 has same area as part of the body.
    4. Rear hatch on Gen 1 extends over back of vehicle, on Gen 2 rear hatch stops ~8" shy of back.
    5. Rear diffuser mounts differently - gen 1 diffuser allows flush mounting with body, gen 2 is offset from body for more airflow in engine compartment.

    Interior
    6. Seats and dash upholstery in Gen 2 slightly nicer than Gen 1 (though dash still doesn't fit without modification in either).

    Suspension:
    7. FFR moved from the yellow Konis (Gen 1) to the black Konis (Gen 2). Unfortunately, the black Koni's cannot be run inverted as they need to be, so FFR now also includes a fix for mounting the black Konis that allows proper installation, but looks like an erector set.

    There may be other changes that I've missed so chime in if I've missed something. Chassis is identical in both. Most all components are identical. Same engine and transmission choices. Same wiring harness.

    -Michael

  3. #3
    VRaptor SpeedWorks, LLC's Avatar
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    They did move the upper front suspension mounts back on the Gen II so you can get more caster, and also made the cam bolt mounting surfaces thicker so that the suspension bolts actually tighten down on the chassis instead of themselves. Don't buy a Gen II thinking that the body fitment has been improved over the Gen I. There are several things on the Gen II that make fitting the body a nightmare compared to the Gen I. Mostly the doors. I'm not sure exactly what the vision was for those, but if Gen I doors are a difficulty level of 8 on a scale of one to 10......I'd say the Gen II doors are a 13. If there was a worse way to design/redesign the doors, I'm not sure what it would be.
    Shane Vacek
    VRaptor SpeedWorks, LLC
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  4. #4
    Senior Member The Stig's Avatar
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    Quote Originally Posted by VRaptor SpeedWorks, LLC View Post
    They did move the upper front suspension mounts back on the Gen II so you can get more caster, and also made the cam bolt mounting surfaces thicker so that the suspension bolts actually tighten down on the chassis instead of themselves.
    Shane,

    with the changes that Factory Five made to the upper front suspension mounts, can you now get the alignment set to the numbers that it needs to be? I don't think that I've heard anyone say.

    Mike
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    Some say, that I only know two facts about ducks, (both being wrong); and that if I could be bothered, I could solve the "da Vinci Code" in 47 seconds...
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  5. #5
    Senior Member Kalstar's Avatar
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    Truthfully there is not much difference between the two. If you are looking to buy a kit you will be fine with either a 1st gen or a 2nd gen. With so few out there finished no one knows what the car is much less what generation it is.

  6. #6
    VRaptor SpeedWorks, LLC's Avatar
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    If I remember right, they moved the upper control mounts exactly 1" back on the Gen II. I do not recall what caster numbers I ended up with, but it was a considerable improvement over the Gen I. I'd say the average caster on the Gen 1 ends up somewhere around 1.8 degrees. I'm thinking that the Gen II we ended up with something closer to 4.5....but don't recall exactly. After almost 20 GTM's on the alignment rack, they all start to run together in my head.......
    Shane Vacek
    VRaptor SpeedWorks, LLC
    www.vraptorspeedworks.com
    Turn-key GTM, SL-C & Ultima GTR Built to Your Specs!
    Offering a full line of GTM Upgrades and Custom Parts

  7. #7
    Senior Member The Stig's Avatar
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    Quote Originally Posted by VRaptor SpeedWorks, LLC View Post
    I'm thinking that the Gen II we ended up with something closer to 4.5....but don't recall exactly. After almost 20 GTM's on the alignment rack, they all start to run together in my head.......
    LOL... Yes, I guess they would!

    Thanks Buddy!

    Mike
    The Stig

    Some say, that I only know two facts about ducks, (both being wrong); and that if I could be bothered, I could solve the "da Vinci Code" in 47 seconds...
    All I know is that I'm called "The Stig".
    GTM #0081

  8. #8
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    I have a Gen 1 (pre-go-kart stage) and intend to relocate the front upper control arm mounts for trackday use. Can someone confirm that they need to be moved back 1" for caster improvement?
    I also plan to lower them a bit for camber gain. Anyone with track experience care to suggest an amount?
    Thanks for the help.
    Ken

  9. #9
    Senior Member Roger Reid's Avatar
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    Don't lower the upper control mounts. It messes up the bump steer.
    Just an old man with a great hobby

  10. #10
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    Roger,
    I agree, it will probably mess it up. However, I don't mind measuring and correcting the bump steer. I had to do that on my Cobra-like kit due to the frame manufacturer lowering the steering rack. Besides that when I move the control arm back, that will roll the upright back, raising the outer tie rod end. That will most likely cause "bump-in" (droop-out). IIRC Carroll Smith and Herb Adams (the two books on suspension that I have) both recommend zero bump steer but say Toe-Out on Bump is better than Toe-In. I am not sure why bump-out is better unless it counteracts the static toe-in resulting in the laden tire pointing straight. On the front, it might have a stabilizing effect (cause understeer) on turn-in.
    I need to read up on the rear. So many of the articles and discussions are based on old solid rear axle cars where bump steer, anti-squat, roll center, etc were very different than our IRS cars. On a solid rear axle car, rear toe-out is very unsettling and is to be avoided at all costs IMHO.
    Ken

  11. #11
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    Quote Originally Posted by Cattrax View Post
    Roger,
    I agree, it will probably mess it up. However, I don't mind measuring and correcting the bump steer. I had to do that on my Cobra-like kit due to the frame manufacturer lowering the steering rack. Besides that when I move the control arm back, that will roll the upright back, raising the outer tie rod end. That will most likely cause "bump-in" (droop-out). IIRC Carroll Smith and Herb Adams (the two books on suspension that I have) both recommend zero bump steer but say Toe-Out on Bump is better than Toe-In. I am not sure why bump-out is better unless it counteracts the static toe-in resulting in the laden tire pointing straight. On the front, it might have a stabilizing effect (cause understeer) on turn-in.
    I need to read up on the rear. So many of the articles and discussions are based on old solid rear axle cars where bump steer, anti-squat, roll center, etc were very different than our IRS cars. On a solid rear axle car, rear toe-out is very unsettling and is to be avoided at all costs IMHO.
    Ken
    Bump induced toe out is desirable because it makes for a quick turn in when entering a corner. Droop toe in is desirable because it makes for a stable car down the straights. Both of which I build into my front suspension setups. Toe out should be avoided at all costs on a GTM. PERIOD.
    www.myraceshop.com

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  12. #12
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    Quote Originally Posted by crash View Post
    Bump induced toe out is desirable because it makes for a quick turn in when entering a corner. Droop toe in is desirable because it makes for a stable car down the straights. Both of which I build into my front suspension setups. Toe out should be avoided at all costs on a GTM. PERIOD.
    Crash,
    In the above quote you say "Both of which I build into my FRONT suspension setups." Any words of wisdom on the rear?
    Ken

  13. #13
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    Quote Originally Posted by Cattrax View Post
    Crash,
    In the above quote you say "Both of which I build into my FRONT suspension setups." Any words of wisdom on the rear?
    Ken
    I'm working on some hardware right now, but the main thing is to not get too much anti squat and to control bump steer. Like the fronts, the lower control arms and mounting points make adjusting to desired settings a "challenge". Shock settings and springs are critical and the addition of an anti roll bar is helpful.
    www.myraceshop.com

    GTM solution kits
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