Hi there,
I'm in the progress of swapping my 75 rubber bumper to the pre 75 steel bumper version.
In order to do it right I need the diameter of the holes to be drilled for the pre 75 bumper mounts.
It would be extremely helpfull if somebody who owns a pre 75 car could give me the exact measurements of the location of the mounting holes.

Thanks a lot!

greetings from Germany....

Entire thread on it. I believe the answer you're looking for is in posts #2 & #3. Good Luck. This has to be one of the top 5 914 upgrades.


http://www.914world.com/bbs2/index.php?showtopic=225743

Actually quite a few threads on it. Pretty easy update/backdate. The holes are sized for the bolts that hold on the bumpers. Mx10 I believe but I could be wrong. The other trick is to use studs in the bumpers instead of blots. Makes it a bit easier to install on the car.

one of the top 5 914 DOWN grades, don't do it

Yeah…..nobody wants their 914 to both look way better AND be 50 or so lbs lighter.

Yea, Porsche designed the 914 to look like 70-74. Big bumpers were made to meet fed impact standards. I’m not saying they are ugly or 75-76 owners should change them but if you like the original look of a 914, it’s a pretty easy swap.

Up voting - Upgrade

great timing, I have been considering the same with my '74 project

thanks to all

once again, this forum totally rocks

I back dated my 75. I found the measurements in on the rear in the referenced thread to be close but just slightly off on my 75. I have a 73 as well to reference. I mounted the lower valance on the rear and set the taillight in place and then set the bumper where it needed to go.

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I used someone else suggestion of short studs and a little dark grease on the dog bones to get the exact locations.
Below are the measurements I got when done. Over all process worked well.

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On front holes are marked as indicated in referenced thread.

I ended up making a whole new front channel as I had some slight rust under the original.

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I have changed to studs on my 73 and it makes installation a easy one person job.

Hope this helps.


john

I hate the Rear BUBs, But oddly enough, I still like the front BUBS that wedge style front is what left its foot print on styles in the late 70"s
So I just back dated the rear bumper
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@rfinegan

Nice SLC! Those are hard to find these days.

That rear bub is ungainly and looks like an afterthought.

I think this looks pretty damn good. You want to change your bumpers, go ahead. I'll even come over and help you if you need help. it's your car and your money, and frankly I applaud you for doing it. That is your vision, and I respect that and I won't call you or tell you I "hate" how your car looks.

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I’ve only ever seen one “front dated” (early car with BB’s).

One too many!!

I did the rear and kept the original front…

Front

My 73 had a updated rear bumper. Front was stock. Update was done less than perfect. I have no idea why it was done. returned to 73 look, which i prefer.
I keep moving the stock bumpers around the garage from my 75, man they are heavy. I don't have the heart to throw them away,,,yet.

john

I weighed the BB’s years ago. Including the shock mounts, one was 38, one was 42. Early bumpers are around 12-14lbs each. Fiberglass is around 6lbs each.