bxtech

Hello all,

Wondering if anyone here has installed a rear 928S4 rear bumper cover to a 1986 or earlier car? I would like to use factory parts vs an aftermarket fiberglass conversion part.

If someone has done, I have a few questions in which I hope someone can help me with:

1) How about the side sections of the S4 bumper that cover the rear quarter panels below the side marker light. Do you cut the bumper cover or the quarter panel? Or, can you mount the cover over the quarter panel?

2) Can the original early rear bumper brace be used with the newer bumper, or is the later S4 brace needed?

3) What did you do about the exhaust opening on the S4 bumper cover? The cutout is of a different shape and at a different location than the earlier car. Change the exhaust/tip? Fill in and re-cut opening?

Thanks very much in advance!

Lizard928

I wouldnt do this.

The lines arent actually 100% the same, so it never quite fits right.
As well you must cut the rear quarter panel, and then bend a lip over to be able to attach it.
Getting this right will be tricky as you have to make multiple cuts to retain the curve.

heinrich

I've considered this many times and would think it a great idea .... and the front especially, to be honest. If you look at where the lights are (distance from floor) the rear cover of the early cars makes a lot more sense. And gives the car a lot sexier low-look.

Mrmerlin

H............what did you say????
what does this mean??

Mrmerlin

this is a conversion thats going to take a lot more work than you have mentioned, the rear body must be cut where the lights of the S4 will reside.( this is under the PU cover, its metalwork)
The lower quarter panels on the car body must be cut off.
you will need to buy new S4 tail lights and rewire them to theoriginal harness.
The rear inner bumpers are the same, if the bumper has been hit then it s a good chance that the rear bumper shocks are toast as they are one time use only.
My suggestion is to fit the correct year parts for the year of the car you have

heinrich

LOL Stan. New cars == big butt. Old cars == low-centred supercars.

heinrich

Somehow I thought he was asking the other way around. old cover on new car.

6.0-928S

I've done this, front & rear.
The hardest part is sectioning the tailite pockets forward in the rear body panel to clear the tailites. The rear bumper rail is different as are the bumper shocks. Trimming the quarter panels isn't difficult. Stevie Wonder could adapt the wiring. If you have a good metal man it can be done, if you don't then buy an S4.

Regards, Hammer

Mrmerlin

Thanks H for the clarification
Hammer thanks,
your correct the early bumper is quite a bit different from the S4

Richter12x2

Actually, in a surprising twist of good fortune, there's a kit made by American International Racing that updates the look of the older cars to the sleeker newer design. It's just very slightly different from the true Porsche pieces, as was pointed out before, the taillights are cast about 1" lower on each side so that it'll fit on the early cars. Unless they're side by side you can't tell. The louvers on the bottom are more obvious, but I still like them.

American International Racing - S4 Update kit When you visit their site, try not to look at the other 928 kits they offer. It'll help you take them a little more seriously. He's a very nice guy and great to deal with, though, despite his apparently feeling that the 928 was missing gigantic sidestrakes.

It requires quite a bit of work to fit, so it might be best left to pros to install, but the front and rear covers, if you buy them together, cost me just over $1k shipped to my door. The most expensive part is acquiring the genuine Porsche taillights, foglights and turn signals from the s4.

Here's a picture of them side by side from our own Post a Picture or GTFO thread:

Here's the kit just installed:


And although it's modified here, it's a really good angle for comparison:

Actual S4:


And same angle AIR kit (louvers cut)


I'm working on my pieces right now, none of the holes for wires and bulb changes are pre-drilled - also, the fitment in some of the buckets is a little off, but with a little shimming to make both sides off the same amount, it'll pass muster. Not quite Porsche quality, but not quite Porsche prices, either.

Z

Here's a picture of a local '84 Euro with the bumper cover from a '93 GTS installed on it. The owner said that the installation ended up being more involved than it seemed like it would be before he started.

6.0-928S

Here's my 86.5 with the GTS quarters & rear bumper installed. Yes I will have dual exhaust.

Stan, Is that Fred's car in your avatar?

Regards, Hammer

bxtech

Thanks for the input and information everyone! I really appreciate it! Boy!, this sounds like quite a bit more extensive than I had thought! The fabrication of the buckets behind the tail lights is a considerable amount of work! I really do like the more modern look of the S4 rear end though!

Richter12x2.......your car looks great! I am familiar with AIR and their conversion kit. I actually helped a friend install one of these a number of years ago on his 1979. I've also met the owner of AIR, and I agree.......He's a very nice guy! Very personable! I bought some fiberglass parts for my 911 awhile back. At that time he had quite a large collection of Bob's Big Boy memorabilia. He had a mini-museum!

Z........thanks for the pic of the car with the GTS rear bumper. It looks great! Any idea on what the owner did for the exhaust? Did he change it or modify for the original?

The fiberglass conversion kit wasn't too bad to install except for a bit of modification to fit as usually expected with aftermarket parts. I prefer to use factory parts for obvious reasons, but the metalwork mods are making me re-think!

Mrmerlin

no but it may be Sharky,
Brians old car, its a picture from SATL in 06
Your GTS conversion looks great, cant wait to see the finished pictures

bxtech

Hammer........Your car looks great with the GTS quarters and bumper! The metal modification work quality looks great! Fantastic job! Please post pics when you are done! Would love to see it!

BTW, the rear bumper support and shocks are definitely different? One person had PM'd me and said that the originals could be used with modification. Are they that different, or do you think it's too much work to modify?

Thanks!