Repop Parts Review 0004 - Urethane Front Bumper (1978-1981)

Discussion in 'Body Restoration' started by CDesperado, Apr 21, 2012.

  1. 70 gsconvt

    70 gsconvt Veteran Member

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    Like most cars of the seventies and earlier, quality control left something to be desired. It looks like if anyone wants a front end to look "perfect", it's going to take a lot of work, whether you use OEM of aftermarket parts.

    It's like the rear wheel wells on my Buick. They vary by as much as 5/16" when trying to fit wheels/tires out back from one car to another and getting the proper backspacing.
     
  2. sbca96

    sbca96 Veteran Member

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    Yes, it certainly flexs. To take the picture I had to hold the grille back against
    the bumper and it definately spread out some. If the aftermaket has more "V",
    its very possible once mounted they are the same.

    Tom
     
  3. CDesperado

    CDesperado Veteran Member Lifetime Gold Member

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    I just wanted to post a few pictures real quick so everyone can see the installed front bumper. (I will have more pics in my build thread, but will post these later.)

    The summary judgement is that this front bumper from GroundUp fits really nicely, but we are having one issue with the gap in the center of the bumper, as shown below.

    [​IMG]

    On the RH side, the gap goes from about 1/8 inch to 1/2 inch, which is pretty dadgum noticeable. I should point out, there are shims behind the bumper, otherwise this would be much worse.

    There isnt a lot more movement we can get out of the bumper, but I have one idea I want to try. If we place a 1/8 aluminum bar between the bumper the bumper panel, as shown below, that might help close the gap enough that this won't be an issue.

    [​IMG]

    [​IMG]

    On other fronts,
    1. My concerns over the opening for the lower grille are not an issue - once the bumper was mounted, the gaps shrunk considerably. There is now less than a 1/4 gap on either side of the lower grille. (I will adjust the original post to reflect this, but leave the original wording there too.)

    Ignore the gaps/ripples of the bumper under the lower grille... the bumper isn't secure to the bumper support braces. We will use a heat gun to smooth out the ripples to make it lay flat. (We are painting the fiberglass panel flat black, but havent done that yet.)
    [​IMG]

    2. Mounting the bumper overall was not difficult - They did have to make minor adjustments to the mounting holes, which was expected. They will be removing the bumper soon and I will take some shots of that so you can see exactly what changed. (I'll do a before/after.)

    3. I mounted my repop upper grille, but was in such a hurry I forgot to look at the gaps. I have an NOS upper grille and will do a side-by-side comparison next week. You can see from the pic above, there is no noticeable issue, but I need to slow down next time and really look at it. (I will edit the original post, as necessary, once I get better pics.)

    4. There is a slight "dip" in the top of the panel, which was in my original front bumper as well. It never really bothered me (the piece is flexible, after-all) and you can barely even see this dip now. However, we will likely put something between the fiberglass bumper support panel and the underside of the front bumper to smooth this out.

    This dip is so slight I hesitate to even mention it and you cant see the dip in any of the pictures I took, but it is there. They had to point it to out to me... I didnt even notice it at first until I got down to the right angle. (In all fairness, I should point out my original bumper had the same type of dip.)
    [​IMG]

    5. The holes under the headlamps and the parking light assembly that are used to secure the front bumper to the bumper support panel matched up exactly .
    [​IMG]

    We have the rear bumper attached to the car as well, but I will save that for another post.
     
    Last edited: Apr 26, 2012
  4. BondoSpecial

    BondoSpecial Veteran Member Lifetime Gold Member

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    That doesnt' fit badly at all. As for that gap, it almost looks like your hood is off center, can you move the hood to the passenger side? and if the fender is too close to do that adjust it accordingly.
     
  5. CDesperado

    CDesperado Veteran Member Lifetime Gold Member

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    That's something else we are looking at. The gap on the RH side of the car running between the fender and the hood is slightly wider than the LH side. We havent tried adjusting yet though. (Having issues with the hinges. I think I need to lube them or replace them.)
     
  6. CDesperado

    CDesperado Veteran Member Lifetime Gold Member

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    I contacted the actual manufacturer of the Urethane front bumper. They have sold a little over 150 of these bumpers so far and no one else has mentioned a gapping issue.... and it is certainly possible this is related to a fender/hood alignment issue.

    The proof in the pudding is the lower air dam (aka, front spoiler) appears to be about a 1/2 inch too wide for the gap.... that is, unless the fender alignment is off, which is pushing the two lower fenders in together a little bit too much.

    I bought the front air dam from Ricks so I am going to call them to see if anyone has mentioned having to trim the spoiler to get it to fit.
     
  7. mgoad1971

    mgoad1971 Veteran Member Lifetime Gold Member

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    Heading to pick up the NOS bumper now, measurements pending.
     
  8. CDesperado

    CDesperado Veteran Member Lifetime Gold Member

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    Ok. Feel free to call me if you have a question about how I took the measurements.
     
    Last edited: Apr 26, 2012
  9. CDesperado

    CDesperado Veteran Member Lifetime Gold Member

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    Update.
    Apparently this Urethane bumper is the exact same bumper sold by Classic Industries. CI has sold about 160 of them and has had a total of 4 of them returned. The reason for the return is listed as "customer dissatisfied with the quality or fit. (FWIW, GroundUp quickly passed me off to someone else when I called. The guys at ClassicIndustries spent time on the phone with me, answered questions, and did their best to be as helpful as they could.)

    4 out of 160 is 0.025%... that's a pretty low return rate, which makes me think this issue is more of a fender/hood alignment issue than an issue with the bumper.

    Does anyone know of a "tips/tricks" thread about bumper/fender/ hood alignments? Maybe we are missing something. :confused:
     
    Last edited: Apr 26, 2012
  10. mgoad1971

    mgoad1971 Veteran Member Lifetime Gold Member

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    Heres my gap issue, you can see where the gap can be fixed by the windshield. 1/4" should do the trick


    .[​IMG][​IMG]
     

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