Installing Fiberglass Rear RS Bumper??

DCOP · 04-28-2002, 06:32 AM

Just recieved my new rear RS bumper from Rennspeed Motorsports. Looking for advice on installing fiber glass brackets as well as what to use for bracket attachments for the L & R bumper end pieces. Obviously all bracket work will have to be fiberglassed to the inside of the bumper? I thought there may be install tips with the bumper but it looks like I'm on my own. Any help would be appreciated.

Colby · 04-28-2002, 08:01 AM

When I installed my RS bumper, I drilled 3 hole in it to line up w/ holes already on the rear fenders. These 6 mounting points held it up fine. I didn't need to devise any brackets or anything.

Colby

katigbr · 04-28-2002, 08:20 AM

DCOP,
I did not have to fabricate any additional brackets on my RS bumpers. I marked and drilled four holes to attached the main section around the engine and then two additional holes in the tabs on the leading bumper areas in the wheel wells.

Mine came as one complete F/G unit with the mount points fabricated.

Rick

911pcars · 04-28-2002, 09:23 AM

DCOP,
I'm also in the process (temporarily suspended) of installing one of Rennspeed's RS rear bumpers. Is your unit devoid of any bracketry? The one I got had the main brackets installed but none for the leading edges next to the wheel well. I thing we're on our own here and will need to fabricate, then glass-in some L-brackets to attach to the factory mounts.

It appears they manufacture two types; one has no brackets at all but uses an extended horizontal area around the engine area to bolt up to the factory mount holes. I think they call this the "race" model since there is space under each "bumperette" for a cut out for twin exhaust pipes. The other bumper has glassed-in factory-type mounts.

That being said, I'm not sure which one you're better off with. My brackets are off about 1/2" on each side which means it doesn't line up with the chassis (more fab time). The leading edges extend about 1/2" into the wheel well and require more than normal force to bring the ends inward toward the body. This is not a good fit. I would return it but I've got about 5 hours into it so far. Being a masochist, I'll keep going, just like I did on my ducktail install.

Hope this helps,
Sherwood Lee
http://members.rennlist.org/911pcars
www.seinesystems.com

Bill Verburg · Bill Verburg's Garage

Not to rub salt into any wounds but the BW Motorsports f/g fit perfectly, and had the correct mounts for the wheel well strut. I attached the rear with 3 or 4 vertical bolts into the quarters per side and the strut.

DCOP · 04-29-2002, 03:47 PM

Thanks guys for the feedback. Looks like I'm in for a little fabrication time....won't be the first...probably not the last!! ...easy on the salt Bill...

jriera · 07-10-2002, 02:59 PM

I'm trying to install one of the Rennspeed rear bumpers (the one's without the mounting points at the wheel well).

Does any one of you have a 'good' set of pictures or recommendations on the L brackets?? also how flush should be the rear piece (the one where the license plate is mounted) with the engine compartment?

I had no problems with the (included) attachments for the engine.

Any help will be appreciated.

Thanks in advance

cary · 07-11-2002, 05:27 AM

Bill is see you subscribed to this thread.

The 930 welting that you recommended for the f/g bumpers.
How did you attach it ? Adhesive or pan head screws ?
I would like it attached. So I don't have to redo it every time I take off the bumpers.

Bumpers go on today.

Jack Olsen · 07-11-2002, 09:15 AM

I'm a fan of Rennspeed, and recommend them a lot. But it sounds like I'll have to put an asterisk on for this particular part. It's the RS-style bumper for Carrera/SC flared cars?

jriera · 07-11-2002, 09:30 AM

I'm my case is the 9" flares for a '73.. kind of dissapointed..

A short while ago I start cutting the mounts on the original bumpers (they where trash anyway) with the hope to be able glass them in the new bumpers..

Bill Verburg · Bill Verburg's Garage

The welting is held in place only by compression and the vertical bolts holding the bumper on. No adhesive.

jriera · 07-11-2002, 11:56 AM

Bill the pieces I just removed from my old bumpers were nicely welded.. I don't see how I can compress anything into the new bumpers.. I will say that the only way to have something firmly in place will be via glassing or with bolts from the outside.

Can you elaborate a little bit more please. Thanks

Bill Verburg · Bill Verburg's Garage

jriera, I was responding to Carys ? about the rolled welting which goes between the steel bodywork and the f/g bumpers. We've been corresponding about ths issue for several months.

As I posted previously the BW pieces are attached with the stock strut behind the wheel well and 3 or 4 bolts per side vertically through the f/g and steel flanges of the quarter panals. I used the stock bumper mounts for some nerf bars beneath the f/g. The 930 roll welting goes between the f/g and the steel and finishes the seam nicely.

jriera · 07-11-2002, 12:47 PM

Thanks Bill, sorry for the misunderstanding, next time I will do some more analysis before buying any f/g parts.