Fiberglass Bumper Reinforcement - Bash bars

merlinfe · 04-26-2018, 10:24 AM

I have a set of fiberglass bumpers for my 911sc. While the front is a direct bolt on (they are GT Racing model IROC bumpers) the rear RSR bumper will require a bit of creative fabrication to mount up (and I'm ok with that).

I appreciate the weight savings and the looks of the bumpers but I don't particularly like the thought of NO protection in case of a small bump in traffic.

My question: Have any of you come up with a bash bar to install behind the front and rear bumpers? If so, do you have pictures, drawings, or plans on how to make them?

My thoughts are to have some exhaust tubing bent to conform to the shape of the inside of the front and rear bumpers and then fill the cavities around them with some type of impact resistant foam. I'll then mount the bumpers to the car via manufactured crash tubes, or the stock US bumper shocks.

I'm sure someone in the Pelican Porsche Brain Trust has done something like this and documented it, right?

- Steve

dwelle · 04-26-2018, 10:31 AM

well, FG is generally chosen for weight saving and often aesthetics. the IB's offer excellent bump/crash protection but are heavy. ask me how i know!

are you only interested in the FG bumpers for aesthetics? i ask because if you start engineering "protection" behind the FG, you're likely to put back quite a bit of the weight you just saved. and it won't likely be as effective as the original bumpers...

merlinfe · 04-26-2018, 11:17 AM

It's a street car, so weight isn't a huge concern, just protection. I'm deffinatley not counting ounces for pounds. Getting rid of the accordians while keeping the car safe is my top concern.

Cory M · 12:29 PM

Here's some examples built by JWE (Jerry Woods), others have built similar, it's basically a 1.5" tube bent and attached to the bumper shocks. I've seen others that just use tubes instead of the shocks but they probably wouldn't protect the car as well. Don't use exhaust tube, it's too thin and weak.

3literpwr · 04-26-2018, 06:11 PM

I'm doing something similar on my rally car. I'm running SCRS bumpers and some added protection is good piece of mind. The weight gain is minimal overall and i'm not a total weight weenie, so it's no biggie.

Jack Olsen · 04-26-2018, 07:08 PM

I don't think putting foam inside the tube is going to do much. But the tube itself will provide something.

I suspect the main function of most bumpers is simply to pass the Federal 5-mph/2.5-mph standard, not to play a significant role in protecting the occupants of a vehicle in a real crash. But I'm not an expert.