Need Help Installing a Fiberglass Bumper

Brother · 07-30-2005, 01:44 PM

I got an RSR type bumper for the SC.

If I don't want to retain any of the impact bumper equipment, what is the best way to secure the bumper to the unibody?

Currently the bumper is getting repaired at a local boat shop. It was a used piece that had plenty of curb scrapes.

911pcars · 07-30-2005, 06:47 PM

"Currently the bumper is getting repaired at a local boat shop. It was a used piece that had plenty of curb scrapes."

I can't vouch for the quality of the bumper, but I would have fitted it to your car first, then made cosmetic repairs. If the bumper fits without add'l surgery, you're lucky. In that you're the second or subsequent owner may be better than the guy who gets to initially tweak it right out of the mould.

Sherwood

Brother · 07-31-2005, 06:09 AM

I'm just getting the curb rash fileed in and getting everything re-gel coated. Then I'll get some brackets built in to it.

I know most people still use the euro shock tubes to install it to the front, but i want to eliminate all of that. I'm looking to more or less bolt it all up to the front.

Brother · 07-31-2005, 07:05 AM

bump

Joe Bob · Joe Bob's Garage

I fabricated aluminum brackets for eachside of the trunk. They extended out and then I used rounded cap bolts. The sides I used zip ties....sounds mickey mouse but it held up to 135mph at Willow Springs.

Tooth911 · 07-31-2005, 07:28 AM

I used 2 bolts at each side next to the wheel well then skrews across the underside of the headlight area of the fender.

Formerly Steve Wilkinson · 07-31-2005, 08:08 AM

Don't know how similar it is to an RSR bumper, but I recently installed an IROC air dam (Getty Design--fit was absolutely perfect). I also eliminated the bumper rams.

The main point of fastening is four bolts and nuts that go through the fiberglas and into the four holes in the front sheetmetal that as I remember were used to hold teh bumper smile in place. The gap of about half an inch between the back face of the fiberglass and the sheetmetal I filled with pieces cut from a rubber hose with about the same i.d. as the bolts, and they are in moderate compression.

A secondary fastener set is a couple of smaller nuts and bolts on each side, vertically through the holes in the fender that previously were occupied by the sheetmetal screws that held in place the rummber accordians.

A final pair of fasterners were small-diameter tubing struts (some stainless steel aircraft fuel line I had sitting around) with the ends flattened, from the bottom of the air dam on each side to points on the underside of the pan.

Stephan

Chuck Moreland · 07-31-2005, 08:12 AM

If you plan to fit an oil cooler behind it, you should consider mounting with 1/4 turn fasteners. This is a great benefit when you are fitting the cooler, and you need to put the bumper on/off numerous times. Also later for inspecting oil lines, cleaning, etc.

On my '73 I hid all the 1/4 turn fasteners so it looked stock from the outside. I wouldn't do it any other way.

Brother · 07-31-2005, 10:17 AM

Tooth, Stephan, and Chuck,

I'm going to remove the original bumper today and take a look.

Stephan, I think I'm probably going the way you did. Great idea to use the fuel line to make supports. Did you resin those brackets in or just screw through it.

Chuck, I'm planning on using the setrab 172 that you recommended on the phone to me a few weeks ago. A couple more months of Porsche allowance, and I'll put the order in.

Thanks for the help. Stephan, I know you aren't usually one to post pictures, but if you have any of your bumper setup, I'd love to see them. The bumber is an RSR.

randywebb · 07-31-2005, 11:09 AM

"On my '73 I hid all the 1/4 turn fasteners so it looked stock from the outside. I wouldn't do it any other way."

- Chuck - can you describe how and show some pics on how you did that? (or is it already in your prev. thread on your car?)

Brother · 08-21-2005, 07:48 PM

Where did you mount the wire that the 1/4 turns hold onto?

Chuck Moreland · 08-21-2005, 07:56 PM

Here is a link with some pics of my 1/4 turn fastener install.

Dzus fasteners secure front bumper, stealth mode

Now several months later, I'm very glad I did this. It makes the front of the car easily servicable.

Brother · 08-21-2005, 08:03 PM

I'm still in the head scratching phase. I want to lose the impact bumper shocks so there isn't a clear way to attach this.

The Getty design has a lip that can mate up flat to the front pan. I have no lip.

widebody911 · widebody911's Garage

widebody911 · widebody911's Garage

Brother · 08-21-2005, 09:13 PM

Not so subtle hint--learn how to weld.

I think three or four of those brackets that you have would work for me. I could just connect those to the top of the bumper and have the tops of the screws underneath where the hood lip covers.

What is the rubber gasket stuff you used between the body and the bumper?

Genius once again, Thom. Now get crackin on those air block off plates!

Joeaksa · 08-21-2005, 09:13 PM

Quote:

Originally posted by Chuck Moreland
If you plan to fit an oil cooler behind it, you should consider mounting with 1/4 turn fasteners. This is a great benefit when you are fitting the cooler, and you need to put the bumper on/off numerous times. Also later for inspecting oil lines, cleaning, etc.

On my '73 I hid all the 1/4 turn fasteners so it looked stock from the outside. I wouldn't do it any other way.

Do a search for Dzus fasteners. This is what they are called and are used all over the aircraft industry.

Or... be brave and backdate that puppy!

JoeA

Brother · 08-21-2005, 09:23 PM

I know what the fasteners are. I'm a pilot. I just didn't see an obvious place to put them. I think thom's brackets are the money. That is probably the easiest and it will make the fastener accessible.

ben parrish · 08-23-2005, 07:09 AM

When I installed my Ruf bumper, I just used the stock holes all the way around. I did not see it necessary to make brackets. I taped the bumper in place with duct tape and marked the center holes first. In the trunk, there are four screws that hold the "smile" in place. I marked these holes on the new bumper, removed and drilled pilot holes, put the bumper back on (tape) and used self tapping screws to secure the center. From that point, I worked my way to each edge marking, drilling and attaching. After all the holes were drilled, I attached it for a final fit and then sent it to the body shop for paint. For the final install, I used the existing body panel clips and put the screws in through the fiberglass using large washers to spread the load. I had no problems using this method other than the tight spaces under each headlight. I did not use any "filler" to close gaps as there were no gaps to fill. This has stood up to 150+ mph runs.
This method would not be the best approach though if you plan on removing the bumper frequently.

Good luck.
Ben

Rikao4 · 08-23-2005, 07:25 AM

Paul, just drive that puppy up here and Pete will install....he has everything...your not playing fair...tough to keep up with ya.But ,I got Island's valve tool( stunning piece of work) remember when we did yours...you HAVE to order one..
Rika