metal bar behind the front bumper

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jarchitype
Posts: 126
Joined: Dec 10, 2007 12:49 AM
Location: Portland, OR

metal bar behind the front bumper

Post by jarchitype »

Hi folks,
I'm trying to install the euro bumper conversion. I have all the parts; euro valance, lights, grills, spoiler and a fiberglass/plastic bumper from classic euro parts. I purchased their mounting kit as well. The only problem I have now is that there's nothing to hold an impact. Prior to purchase I figured the fiberglass bumper was somehow structural, but it's not. Is there a steel bar inside the US bumper that I can use to attach to the circular mounting points (where the rams used to live), and then glue the fiberglass bumper over top? I'm not sure if classic euro parts intended their product to be structural.

Happy to receive any and all comments! Thanks in advance.
Mike W.
Posts: 26872
Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: metal bar behind the front bumper

Post by Mike W. »

Simple answer, no.

That's the generally unspoken conundrum between US and Euro bumpers. While large and unsightly, the US bumpers serve a purpose, they'll take a light hit with little or no damage due to the large and thick aluminum. The Euros, while cosmetically nice, are listed in parts as "Trim" and with good reason. A good kick, let alone impact with another car will dent or bend them. Let alone a fiberglass version.

I think I see where you're going, and while rarely asked, it's not a bad question. But if you want a stiffener, I think you're looking at buying say a piece of
~3/16 (or 1/8, or 1/4, or ???) X 1-1/2 X 4' steel and working it to shape. Probably a somewhat sharp small bend in the middle with a vice and just hand working it from there. I'm winging it on size, but you could buy a piece of steel bar and install it behind the plastic to give at least a little bit of strength to it.
Ordnator
Posts: 550
Joined: Aug 31, 2015 7:34 PM
Location: Halifax NS

Re: metal bar behind the front bumper

Post by Ordnator »

If you have the M535 plastic front bumper and the rear plastic bumper then I believe they mount over the top of the euro bumpers, which is where they obtain their structural integrity together with half a dozen assorted brackets and braces.

That said who actually looks behind the body kit, so fabricating something to take its place, if you are so inclined, could be an option.

Failing that you will need to look for a half decent used set of euro bumpers and brackets, these will not need to be cosmetically good because they won't be visible behind the body kit, but they will need to be reasonably straight for the body kit to sit straight.

Owning euro e28's, I agree with Mike that the euro bumpers rarely survive contact without damage. More "decorational" than "operational".

Best regards,

Mick
Mike W.
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Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: metal bar behind the front bumper

Post by Mike W. »

Actually it's kind of funny, I did something like this on my Datsun, the QX4. It had literally no metal behind the bumper cover below, oh, just under waist height. And as far as I can tell that was just to hold the "bumper cover" up. (how it an be a bumper cover with no bumper to cover I don't know...)

Anyway, I do a bit of off roading in this and wanted at least a minimal ability to push something more than I could with my knee. So I shaped a 2x4 to the contour of the bumper cover and mounted it against the beefy subframe. I might upgrade it with a 2x6 this winter even though I haven't had to use it. A bit of work, and not factory or concours, some time, but lots cheaper than euro bumpers and perhaps even more effective. :shock:

The front is off to the left. Yes, the purists of either marque will be screaming, but oh well. :laugh:

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Federico
Posts: 545
Joined: Sep 16, 2013 6:38 PM
Location: Argentina / California

Re: metal bar behind the front bumper

Post by Federico »

The euro bumper serves as a chrome molding. Other euro cars have proper stout stampings, but BMW went for the lightweight/decorative style.
The brackets are also fragile. If you could fit a stronger bumper, they would bend easily.
alpine23
Posts: 31
Joined: May 10, 2020 12:37 AM
Location: Tucson

Re: metal bar behind the front bumper

Post by alpine23 »

When the imported euro cars were federalized in the US, they did weld ghastly heavy metal beams in the bumper carrier are you are suggesting. I have found them in E23 and E24 euro front bumpers so I assume it would have been the same for imported E28. To be honest, I'm not sure how much added "protection" you get with the welded reinforcements.
vinceg101
Posts: 4802
Joined: Jun 20, 2007 2:40 AM
Location: Los Angeles, CA

Re: metal bar behind the front bumper

Post by vinceg101 »

alpine23 wrote: Dec 19, 2020 11:18 AM When the imported euro cars were federalized in the US, they did weld ghastly heavy metal beams in the bumper carrier are you are suggesting. I have found them in E23 and E24 euro front bumpers so I assume it would have been the same for imported E28. To be honest, I'm not sure how much added "protection" you get with the welded reinforcements.
I can confirm they did. Federalization of EU cars was a mixed bag in the execution of stuff like bumper reinforcement.
This was what was under my rear bumper (in my case the MTech rear valance with the EU bumper underneath):
Image
Image

Oh and besides a few ST body screws around the wheel wells and rear quarters, the only thing holding this whole hot mess to the back of the car are those 4 M10 bolts and nuts through the back tail panel. The nuts are accessed from the inside of the trunk.
This further emphasizes that the EU bumpers are merely "trim".
Beils
Posts: 36
Joined: Jan 30, 2014 11:45 AM

Re: metal bar behind the front bumper

Post by Beils »

Those numbers are 5 mph US solutions, up from 2.5 mph requirements. The legislators ruined the aesthetics of every car model from 1974 until recently. Guess what the number standard is now? 2.5 mph...
Mike W.
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Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: metal bar behind the front bumper

Post by Mike W. »

vinceg101 wrote: Dec 19, 2020 12:09 PM
Image

Oh and besides a few ST body screws around the wheel wells and rear quarters, the only thing holding this whole hot mess to the back of the car are those 4 M10 bolts and nuts through the back tail panel. The nuts are accessed from the inside of the trunk.
This further emphasizes that the EU bumpers are merely "trim".
Wow, that's some iron back there. What is it, 1/4" wall thickness? I'm guessing it's heavier than the aluminum US bumpers. Not exactly well formed to shape or pretty welds either. :shock:



Beils wrote: Dec 20, 2020 5:40 PM Those numbers are 5 mph US solutions, up from 2.5 mph requirements. The legislators ruined the aesthetics of every car model from 1974 until recently. Guess what the number standard is now? 2.5 mph...
The 2.5 MPH standard was only interim and brief before the 5 MPH. Previously there was no standard. The bumper standard was the result publicity of astronomical repair bills in very low speed accidents. The current standard is only to "safety" related systems I believe, mostly meaning taillights or the inability to open a door.
ilovemycat
Posts: 173
Joined: Jul 03, 2017 4:05 PM
Location: victoria bc

Re: metal bar behind the front bumper

Post by ilovemycat »

if you are driving a classic car with the intent of crashing it you might want to think a bit harder...
ThaiTalion
Posts: 21
Joined: Nov 28, 2020 3:51 PM
Location: Virginia

Re: metal bar behind the front bumper

Post by ThaiTalion »

I purchased a used set of euro bumpers and the PO said he reinforced them. Looking at them there is a metal tube welded on the inside. The rear bumper was dented, which bent and cracked the side pieces. This may have saved the car from additional damage, but the bumper is ruined.
tn535i
Posts: 5585
Joined: Jul 14, 2006 1:30 PM
Location: Middle Tennessee

Re: metal bar behind the front bumper

Post by tn535i »

I imagine even an 80's BMW with trim bumpers is still less expensive to repair than any newer car with 2.5 mph bumpers. Show me anything that will not be damaged by a 2.5 mph hit. Even a scuff on the big wrap around urethane bumpers means a $700 or higher repair bill for paint alone. On my sons Subaru there are spider cracks from a minor bump, the body shop said it was cheaper to replace the whole urethane piece than to repair and paint the old one.

That steel tube 'federalization' above would surely transfer small impacts to the body of the car NOT anything structural. It's NOT engineering.

Isn't it amazing that when you get into these government mandated but still grey areas, the stupidity that is found.
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