Cary E

Well, my project has begun. Pulled off my rear bumper. I have a new 74 IROC/RS rear bumper in my hand. The question is the trim pieces. Looked thru GT-Racing catalog, some trim and some don't.
What have you guys done.
How do you attach the bumper to the body ?

Heres the trim in question ?

There is a seal under the reflector. But nothing under the tail lights.

Howard

Cary,

Some fiberglass bumpers have the studs glassed in so you can use the stock bumper shocks to mount to, along with the 2 supports that extend down from the tub on both the driver and passenger side. You will also need to use a few screws to secure the new bumper to the 1/4 panels as well. Most guys restoring or building replicars will trim, guys that race don't, the trim material is expensive and it's a PITA to make a nice job of it. FYI

Good luck !

James Achard

Cary, I just completed installing a GT racing front bumper and here are my suggestions.

1. Get some small C-clamps to "dry" mount your bumpers to the car. This way you can get the bumper where you want it in relation to the fenders etc. before you start drilling holes in it.

2. In regard to sealing, I just used a bit of silicone caulk since it adds a layer between the metal fenders to prevent rusting. Also, when it rains you don't have debris seeping out between the fender and the bumper. My car is black so I just got the black caulk and put some on once I had all the holes drilled and the mounting all set.

I found that the front bumper brackets and the holes they mounted to on the bumper were incorrect so I ended up drilling some new ones. Not a big deal but this just stresses the importance of dry mounting to get everything perfect before you caulk, if you decide to go that route. Good luck!!

James

Bill Verburg

Cary,
Jim A. gave some good advice about the clamps. I used BW motorsports bumpers on mine. drilled thru the f/g and fenders, bolted up with washers.
I used 930 welting between the bumpers and body. It comes in a roll, cut to fit, 1 roll does both ends of the car. I think that the part # may be 999 911 205 40 for 76-80 930(my notes are a little vague on that point)here is the final result;

Cary E

Thanks, James and Bill.

James, if my car was a dark color I could go with out. But white, I need the color break. Thanks for the tip on the c-clamps. I have some little tiny ones.
As for re-drilling the front braces. No problem, being a EURO, no 5-mile hour shocks. Just a frame deal.

Bill, I'm on that 930 welting. That will work.

I assume the BIG seal under the rear reflector must come out. Seems TOO big.

Engine is out for gear box enhancement.
So lots of room to work.

Thanks for the help .........

pd'83SC

Cary,
..I have just completed a similar installation on my '83SC. In addition to the above mentioned points, I will add that after fitting up the bumpers, drilling and mounting, I removed both bumpers and trimmed the wheel-well flanges down to match the factory widths...a nice, finishing touch for those that notice the details.

PD

Cary E

Thanks, pd'83SC.
Saw that too. Was giving that some thought also.

Cary E

Thanks again Bill, my roll of Turbo beading is on it's way. The # was correct.

Ran across something removing the rear bumper. I don't have shocks. Just the square tube and a couple round tubes. May look at "glasing" them to the bumper from the inside.

Bill, did you remove the original seal under the rear "Porsche" reflector ? Seems waaay to thick to line everything up.

Bill Verburg

I ran the 930 welting from wheel well to wheel well including under the center reflector, it's a long roll. It finishes the joints nicely. I used my original solid bumper mounts(the same ones you have) for nerf bars under the f/g front and rear. The front nerf bar does double duty as an oil cooler mount. To do this the oem bumper struts were swapped front to rear and vice versa, one set needed to be shortened to fit behind the f/g(I forget which).

The thru bolts into the fender flange and the oem bottom struts by the back wheel provide a very sturdy mounting method.

Cary E

Got yah........

For future searches, the roll is 5 meters long.

Cary E

Bill, do you have a JPEG of front hood to bumper seal without using the "smile" ? I've seen your's from the front. But not from the top.

TIA

Bill Verburg

This is the best i've got up right now, I'll try for a better angle when I get some time this week.

Cary E

I'm back ..........finishing up my project.

How do you attach the turn signals into the bumper ? They fit recessed back in like RSR on page 23 of the GT-Racing catalog. I didn't like the gap left if you left them out flush. Too much space all the way around. IMHO.

I'm thinking a couple sheet metal screws thru the F/B into the signal case. Then neatly silicone them in.

But I'm looking for a BTDT. TIA

CAporsche

I'm reviving this because it fits better than starting a whole new thread. What is the best way to correctly cut the exhaust hole into one of these bumpers? I was thinking of just starting with a small cutout and then dry fitting, expanding the hole and repeating until it's correct. But is there a "right" way to do it?

intense1

I've repaired many surfboards, but never one of these bumpers... So I would say that if it's fiberglass, and they used normal resin (not epoxy) then a repair would be pretty easy... Just get some bondo resin and some fiberglass cloth from the nearest hardware-type store and go for it. If you still have the piece you removed you can glass that back on. There are hundreds of tutorials on the tube of u.