Brackets Behind Bumperettes Options

[doug_b_928]

I removed these brackets (see pic below) from my 74 parts car front bumper. There were no such brackets on my 73 front bumper, but I supposed they could have been left off by a PO. The PET diagram doesn't show them... Are these brackets OE and, if so, were they on all 70-74 front bumpers? They look like stock pieces, fit perfectly between the bumper and the bumper mount bracket, and make sense to beef up the bumper a bit.

[Rusty_Rivets]

Likely the difference between models sold in the US and Canada/rest of the world. I think only the ones sold in the US had the bumperettes, due to the US 5 MPH bumper regulation:
https://www.carscoops.com/2022/09/50-years-...rs-fought-back/

My Canadian '73 doesn't have them.

[doug_b_928]

Canadian cars had the bumperettes the same as the U.S. cars. One of the few differences I'm aware of is that, as far as I know, all/most Canadian cars received the schutz undercoating, but not all US cars did. Oh, and the Canadian import sticker in the door jam, of course. But I digress... I'm referring to the steel brackets in the pic that sit behind the bumper and add reinforcement to the bumperettes by sitting in line with teh bracket that's welded into the bumper itself, which then receives the bolts to hold the bumper to the car. My 73 didn't have these steel brackets to help reinforce the bumperettes, but the 74 parts car did. I'm a stickler for originality but these brackets look like a good idea so I'll likely restore and use them on my 73 regardless, but I'm curious if my 73 would have originally come with them or not.

[dtmehall]

I have a 73 us model. my car has no such brackets.


mine was fitted (documented in many posts here) with 'dog bones' rubber reinforcements behind the bumper

i would think that a 73 bumper would be a different shape than yours since you have because of these much larger braces

[doug_b_928]

I should clarify, the braces pictured essentially bridge the back side of the bumper (where the bumperettes bolt on) and the front side of the bumper bracket (opposite side of the bracket to where the dog bones go). I should have taken a pic of them in situ. Sorry I’m not doing a good job of explaining this…

[bdstone914]

I should clarify, the braces pictured essentially bridge the back side of the bumper (where the bumperettes bolt on) and the front side of the bumper bracket (opposite side of the bracket to where the dog bones go). I should have taken a pic of them in situ. Sorry I’m not doing a good job of explaining this…

They are OE and i dont use them. All they do is dent the front panel. I dont the bumperettes either. Without them you have a few mire inches before you hit something.
If you hit anything with the bumperettes it bends the bumper.

[doug_b_928]

Thanks, Bruce, for confirming that they are OE.

[wonkipop]

@doug_b_928

i don't believe those brackets positioned behind the bumper horns are strictly original.

its been a while since i had my bumpers off during recommission. about 5-6 years ago.
but definitely don't remember anything exactly like that either front or rear.
and i think i would have remembered. and i have a very original unrestored car.

if i remember right, mine where more like this as illustrated.
i don't recall they had side flanges taking the bumper horn bolts through them.
but its been a while since i was in there.

its possible they changed the brackets along the way a bit during 74 and modified them.


EDIT
i wonder if someone modified rear reinforcement brackets and used them on the front bumper. i know the rear reinforcement lines up with the dog bones and attachment point and the rear horns are set directly over those.

but its different at the front. the horns do not line up with the dog bones and attachment point of the bumper. more inboard and horns are longer. it would be pointless to reinforce the bumper with those as its difficult to see how that would transfer load directly back to the body. i can see how they work at the back.

i would say its a mod of some sort if on the front bumper. i really do not think its there on mine at all. pretty sure the horns are directly fixed on with a washer and a bolt head from behind. but no reinforcing bracket to best of my memory.

[doug_b_928]

Yes, where you have circled in red is exactly where those brackets were but on the front bumper of my 74 parts car.

[wonkipop]

Yes, where you have circled in red is exactly where those brackets were but on the front bumper of my 74 parts car.

yeah - see my edit. bottom of post.

i'd have to take the bumper off mine to confirm, not something i plan to do. (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/biggrin.gif)
but am inclined to agree with you. not normally on front.

[dtmehall]

doug_b_928

given the photos above, where are you saying this 'brackets' are inside the bumper?

do they replace the factory bracing shown in the photo

(IMG:style_emoticons/default/wacko.gif)

[dtmehall]

doug_b_928

given the photos above, where are you saying this 'brackets' are inside the bumper?

do the replace the factory bracing shown in the photo

(IMG:style_emoticons/default/wacko.gif)

[doug_b_928]

They were exactly like where the arrow is pointing to in the illustration. The only difference is, as shown in the photo in my first post, the ones on my parts car have flanges on the sides so that the bolts from the bumperettes pass through the bracket. The washer and nut that hold the bumperettes are then installed, holding the bumperettes and the bracket in place. The bracket fits snugly against the brace in the bumper. Theoretically it should act to make things stronger.

[JeffBowlsby]

What’s the source of that graphic above? I’ve not seen that before.

As Bruce says above they are OE, the graphic indicates on ALL 1974 cars. I’ve owned several 1974 cars and maybe 1-2 had them. Front bumper only. Other than that the only thing I can think of is that there was a shirt period hear in the USA that required 5mph bumpers. Not sure if this was an early attempt at that, the 75-76 bumpers shocks clearly were.

[Rusty_Rivets]

Interesting. My '73 doesn't have bumperettes on either front or rear, and no mounting holes for them in the bumpers either.

[wonkipop]

Interesting. My '73 doesn't have bumperettes on either front or rear, and no mounting holes for them in the bumpers either.

then it does not have its original bumpers.
a 73 had them on the front.
not surprising after half a century given the tit hate out there - side by side with the wart hate (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/biggrin.gif)

personally i have grown to love the tits front and rear on my 74 and its warts and all looks. but you know - i'm a weirdo. (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/biggrin.gif)

[wonkipop]

What’s the source of that graphic above? I’ve not seen that before.

As Bruce says above they are OE, the graphic indicates on ALL 1974 cars. I’ve owned several 1974 cars and maybe 1-2 had them. Front bumper only. Other than that the only thing I can think of is that there was a shirt period hear in the USA that required 5mph bumpers. Not sure if this was an early attempt at that, the 75-76 bumpers shocks clearly were.

graphic is from factory workshop manual jeff.
and its only showing for the rear bumper. not the front.

the regs re bumpers for the USA were as follows.
73 - front bumpers were required to absorb 5 mph impact.
crushable. but no requirement to recover.
74 - front and rear bumpers required to absorb 5 mph impact.
crushable. but no requirement to recover.
75. front and rear bumpers to absorb 5 mph impact.
required to recover after impact. hence shock absorber set up.

the tits in 73 and 74 did the crushable absorption job.
but were not up to the recover aspect in 75.

the reinforcements are in my rear bumpers from memory.
i'm resorting to remembering how it was 5-6 years ago when i had them off.
there was no such thing in the front bumper from memory.
perhaps i should take them off again to really refresh things in my mind.

but being logical for the moment.
and thinking as an architect, ie psuedo structural engineer.
i can see how they work with the rear horns (or tits as we say).
the rear horns are directly aligned over the bumper fixing point.
and the observant amongst us will note the rear horns are not as deep (long) as the fronts. yet both bumpers were apparently 5 mph absorbent structures.
so i figure that the shorter horns along with the reinforcement directly aligned with the fixing points were doing the job with a certain amount of force transfer directly back into the body of car and became forward momentum with no shock the body of the car.

and the front has longer tits and neither of the tits are aligned with the bumper fixing points. further inboard on the other side of thee fog light openings. there would be little point to the reinforcement brackets as they do not transfer the impact load directly into the bumper to body fixing points. so the tits are taking most of the impact load and crushing?

of note there is nothing in the factory workshop manual showing anything behind the front bumper tits.

as to the PET, no mention of any of these brackets, front or rear. its only mentioned in the factory workshop manual.

and as i say i have no recollection of coming across this when i had the bumpers off my car in relation to the front bumper.

mine is a jan 74 build. thats not to say they did not add them later to front bumper.
and thats not to say my memory is not faulty in thinking they were not there on mine.
but i don't remember seeing them.
and there is no mention of front bumper reinforcement brackets in factory manual.
but they do show the rear reinforcements.

? (IMG:style_emoticons/default/confused24.gif)

---

interestingly as a post script with reference to the 911 functional crush bumper update.
the USA cars carried the piston to recover the bumpers from an impact, front and rear.
from 75 on.
and in the rest of the world, despite having no regs anywhere regarding impact absorbing bumpers, porsche fitted crushable bumper supports anyway with their "facelift" functionally expressive bumpers. they crushed after an impact but did not pop back.
all the post 75 911s sold in aus had the crushable bumper fixings and the accordian detail on the sides of the bumpers.

and as a further postscript.
i believe when the 914 was first being designed and modelled the idea was it had spring mounted parking nudge absorbing bumpers.
but this was dropped before production.
i think its still very evident in the red piech 914/8.
the moulding on the top of the bumper in that prototype car is attached to the body of the car and not the top of the bumper.
it is entirely evident to me that the bumper was intended to move backward and the polyurethane top moulding is a kind of cover strip or as we say in architecture, a good old quad moulding to cover a gap. (IMG:style_emoticons/default/biggrin.gif)
also explains the indentations in the body to receive the bumper so to speak still evident on all the production cars.
and at that point in time, what 1967 or 1968 there were no USA bumper regs proposed.
either porsche had a crystal ball or were just plain thinking ahead.

[wonkipop]

i realise i could just undo one of my non foglight grilles and see if i can peer in there with a torch. might do that. getting curious. about the bumper and my memory.
good senility test. (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/biggrin.gif)

[doug_b_928]

Based on the thoroughness of your posts I have no concerns for you regarding senility (IMG:style_emoticons/default/wink.gif)

[DC_neun_vierzehn]

I have a ‘73.

I took the bumperettes off shortly after buying the car 5 years ago and plugged the holes with black plastic caps/plugs. I had to take the bumper off yesterday to change the fog light lenses (easier to do with bumper off and I wanted to see how to make the front hood catch pop open if I ever needed to use the peep hole behind the bumper).

I can confirm that mine DOES have the steel bracket reinforcements nested in the framing. Mine weren’t loose though. I wonder if a PO welded them in at some point. If they were loose I would have removed them. But they wouldn’t budge.