71-72 bumpers on a 73

[Hemikiller]

Did you still need the bumper reinforcement plate for the chrome bumper?

Yes, the reinforcement plate is what the bumper and the arms mount to.

 

[Ripper679]

Sweet thanks!

 

[AcesArneson]

Yes, the reinforcement plate is what the bumper and the arms mount to.

Is this reinforcement plate part of the original 73 Urethane bumper or does it need to be purchased separately?

 

[Ripper679]

Is this reinforcement plate part of the original 73 Urethane bumper or does it need to be purchased separately?

It needs to be purchased separately if swapping over to a chrome front bumper. The bumper brackets bolt to the plate, the bumper also bolts to the plate. It's what connects the bumper to the bumper brackets, as the bumper brackets don't connect to the bumper itself, like in earlier mustangs.

 

[Hemikiller]

Is this reinforcement plate part of the original 73 Urethane bumper or does it need to be purchased separately?

The plate I was referencing is the 71-72 stamped part. The 73 bumper has a box section assembly that the urethane cover attaches to.

 

[AcesArneson]

The plate I was referencing is the 71-72 stamped part. The 73 bumper has a box section assembly that the urethane cover attaches to.

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View attachment 86397

Thanks HK, I haven’t seen a 71/2 set up before. This helps. I can’t find a complete set up for under $650. I wish we had parts yards in Canada like you do in the US.

 

[AcesArneson]

Bit the bullet and ordered the 72 front bumper package. Thanks for the help guys, I have now reduced the total front end weight by approximately 170 lbs.

 

[351c1971]

Add an aluminum intake and trans belhousing to the equation and the weight reductions are significant.

 

[AcesArneson]

Add an aluminum intake and trans belhousing to the equation and the weight reductions are significant.

Yes I included the aluminum intake but the transmission is one piece just like my old FMX. I will have to look into the weight difference between them to make sure I am close on total approximate weight.

Thanks

 

[351c1971]

Yes I included the aluminum intake but the transmission is one piece just like my old FMX. I will have to look into the weight difference between them to make sure I am close on total approximate weight.

Thanks

Interesting to note the 72 Mustang 3 speed toploaders had the same aluminum belhousings as the Boss 302. That’s how I found mine.

 

[AcesArneson]

Add an aluminum intake and trans belhousing to the equation and the weight reductions are significant.

Looks like most estimate the FMX at 170 lbs and the 4R70W at 180 lbs. doesn’t look like I will be saving weight there, but the electronic shifting and extra gear are the real reasons I wanted it anyway.

 

[351c1971]

Yes the overdrive gear is a huge plus. With a 3.25 rear, I turn 3,000 rpm @ 65 mph. Fortunately my highway trips are limited.

 

[Spaceman]

Bit the bullet and ordered the 72 front bumper package. Thanks for the help guys, I have now reduced the total front end weight by approximately 170 lbs

Let us know how it goes, and take pics if you can. I have the same project planned in the future for my 73!

 

[AcesArneson]

Let us know how it goes, and take pics if you can. I have the same project planned in the future for my 73!

Will do!

 

[AcesArneson]

Need some more help from guys who have done this conversion. I received my side bracket mounts today and I am still waiting for the bracket that mounts to the bumper. I read back and see that some guys welded an extension onto the '72 brackets to fit the original '73 welded nut holes. My '73 has 4 holes on each side; 2 have the welded nuts for bolting on the '73 bracket but the other two holes are unused. When I line up the holes on the '72 bracket, it sits level horizontally if the hole at the back of the bracket goes in to the back original welded nut location and the front hole on the '72 bracket lines up with the front unused hole. If I had the front mounting bracket I would just test fit it but it looks like it is delayed 2 weeks.

 

[Hemikiller]

@AcesArneson If you can document your process, we can build a thread and make a tutorial on the process.

 

[351c1971]

My installation matches your picture. Good job!

 

[AcesArneson]

@AcesArneson If you can document your process, we can build a thread and make a tutorial on the process.

Will do.

 

[Ripper679]

Will do.

Ok. This is what I did; right, wrong or indifferent..... it came out pretty nice and the bumper sits close to the body. My car is in pieces at the moment but I took some pics of what I did.

1. First and foremost.... kinda mock everything up to get an idea where everything lands on the car. Use C clamps or large vice grips to clamp the brackets into place. Its going to look really, really, really bad. But you will be able to see where everything has to move to get it about where you want it. Adjust the position of the brackets by loosening the clamps until you get at about right. I will warn you... I had to do some bending and tweaking, (after the bumper brackets were modified and bolted to the car with the bumper assembly attached) as my bumper was kinda, "nose up" after everything was finially bolted up. Nothing major, just used a rather large crescent wrench to bend the bumper, "nose down" to get it to look straight. I will explain what I did below in more detail. My end result was a bumper that hugged the fender at the proper angle. Yes, you can tell that it isn't quite, "perfect, made for the car OEM". That said,.... it looks real good and will pass the sniff test for just about everybody who looks at it. AND IT DOSENT WEIGH 100 POUNDS! It's not about trying to get a 50/50 weight balance.... it's about removing a massive boat anchor weight hanging out in front of your tires.... which is absolutely horrible for handling characteristics for those of us who are more inclined to engage in track or more spirited driving styles.

Sorry.... rant over.... I digress......

2. I took the bumper bracket and drilled a 7/8 hole at the end of the bolt hole slot. See pic. You can kinda see where this needs to be on your mock up with your C clamp setup.

3. I then cut two notches in the front of the bracket and bent the metal down... to make a mounting tab and drilled a 7/16 hole in it for a through bolt and nut for the front mount. See pic. I picked up the hole that was already existing on the bumper bracket mounting surface.

4. At this point you bolt everything up (not overly tight... just mock up) and see where you are. My bumper, as mentioned earlier was kinda nose up.... not the right angle. Your mileage may vary here. I took a big ass crescent wrench and bent everything down equally on both sides. This kinda also bent the mounting tabs that are on the mating panel between the bumper and the two bumper brackets. This needed to happen to get my bumper straight. Just a little, "tweaking". It didn't take very much, actually quite minor. Still bolts up fine and looks good. See pic.
Hope this helps.
It may be all wrong.... but it's what I did and it is solid. I repainted my parts and called it done.

 

[Paul M]

Once you get this together, (meaning assemble the brackets on the bumper) the rear bolt and nut plate assy will line up fine, however, you'll have to elongate the hole a bit to get the angle correct. Look at the picture of the previous poster (back hole only) The front bolt hole will limit how far back you go. It's best to relocate the forward hole a little further back and a little higher for a good tight fit. I believe I relocated the hole where it mounts to the frame. I can't remember whether I welded in a new nut plate.