Still need to put them up to the test, the ones I've built here will not work with the stock bumper as it does not have the holes to bolt through it, and that version will have a slightly thicker and longer C channel welded onto it (Most likely 3/16" thick vs the 1/8" thick shown here). The reason I did this one as such is because my Mariah front bumper doesn't fit into the stock shock C channel, I had to cut it back.

Anyhow to the good stuff, the replacements are 2.5lb in weight savings each, weighing in at a mere 0.5lb. Here's a couple pictures of it, let me know if you guys would be interested in more items such as this:







Sorry for the bad cell phone pictures, left the camera at home today.

 

Sam, I just might need a set of those.

Just for your sake, is there any problem (potential lawsuit) with modifying a safety device like that? I hope not, because I like it, but I'd hate to see you get into a jam over something like that...



.

 

Hey Mark ,

I'll shoot one over your way for testing. As for legal issues, yes there is and there will be a disclaimer saying its only for off road purposes. In all honesty all those do is take a bit of impact at very low speeds, if you hit something at 60mph or so those will do next to nothing.

 

Not really SCCA CSP legal but who's going to look there? I might be interested also. As long as they fit the stock bumper.

 

I know from experience they work well up to about 30 mph and saved my car from
any real damage except the headlights were up and they got tweaked a bit. Bumper
popped back out and after I pulled on the headlight buckets a bit, you couldn't tell
I'd had an accident. The other car got its entire rear bumper skin torn off and was
laying on the ground. This was in about 87 and it was one of those Pontiac
Grand Ams. It was a chain reaction panic stop in the snow back when my car was
a DD in Pittsburgh.

Now SA bumbers, those are heavy. I hear folks mount FB bumper shells on SAs to get
rid of the extra weight. These would help there I'm sure.

 

if you look at the JDM cars, they almost all have put the FB front bumper, or a fiberglass one on. the odd part is that the FB guys seem to want to run SA REAR bumpers.

 

I don't like the idea of compromising a designed safety device.


Kind of like replacing the plastic sheer pins in the steering column with steel roll pins

 

With all due respect, I'd have to disagree.
First off, this is not a part that is being "mandated" that you replace, secondly, it is sold specifically as an "off-road/racing" part, and finally, soooo many more cars being boosted, blown, ported, or otherwise "race prepped" without regard to brakes/suspension/routine maintained/other safety mods.....makes this seem kind of trivial....
just my $.02

 

Hm, I wonder if you could shorten those and get a "tucked in" bumper look. I think I remember something about people drilling a hole in the shock, then compressing it, so that the bumper would be in further. From what I remember, it looked pretty cool too.

 

Finished the other side last night and powder coated them real quick, finished at 2am ... Here's a couple shots of the finished product.

As for "safety", these will still take some of the impact by binding the aluminum pieces vs transferring the energy to the frame and kinking that. The reason I wrote "safety" is because I personally do not see them as a real safety measure, but more a product to reduce damage to the frame from smaller accidents. So instead of having to straighten the chassis, you would just replace these and smaller pieces. Doing some quick google searching most of them are rated from 5-15mph accidents.





On another note, they don't seem to be to safe for fire fighters ...

http://www.youtube.com/watch?v=NPajWzThRy4

 

http://www.nhtsa.gov/cars/problems/s...per/index.html

Found a good article to prove my point

 

while i kind of feel weird about removing a "safety" device, one has to remember that the JDM cars actually have a bracket like this instead of the shock.

also you have to think about how big the crumple zone of the car still is, my triumph has the steering box right behind the front bumper, with a solid steering column, which means if you hit anything you're dead. the Rx7 has the steering box BEHIND the front wheels, so you have to bend like half the car before the steering column will even move.

so impact on safety is probably minimal, and indeed that's how the car was sold in some markets. the JDM cars also lack the big bar in the doors that we get, at least for a while.

 

I love the weight saving philosophy behind what you are trying to do this these parts.
You should list out all the weight savings parts you've come up with just to see the potential totals savings.

I think that calling the shock a safety device is an overstatement. It's more of a consumer protection consideration so that when touching a pole in the parking lot you won't cause yourself $1000 worth of damage. I think about the SUV's that have the spare tire on the back hatch. If you back one of those things into a parking lot pole at 3 mph you will destroy the back hatch since the spare tire is above the rear bumper. I saw some video of these tests on TV, and the damage was upwards to $10,000 or more depending on the suv.

Legal wise, what's so different about doing this mod vs. the nerf bumpers and brush guards that people put on their trucks? I had those double 4" round steel nerf bars on a Toyota mini-pick-up, and I think it saved me from many parking lot repairs in college. There were at least 4 instances when I could definitely tell that someone hit my truck, but I had no damage. Someone once left their license plate jammed onto my bumper. Another time my truck was moved around in the parking stall. There may still have been crumple zones, but it was on the other guy's car.

If you want a safe car in a collision, then what are u doing with an RX7? Plenty of cars now a days with air bags all around and doors that can't stick you arm out of.

The guys recording the car fire.....Canadians eh?

Takes a lot of water to put out a car fire!
Suddenly my fire extinguisher seem inadequate.

 

Mythbusters did an episode on the exploding bumper shocks.

http://mythbustersresults.com/exploding-bumper

 

if you can make them fit the stock bumper i might be interested in a set or 2

 

If they will fit an SA you can send me two,(or four if they will work on the rear as well).

My SA Bumpers are heavy as hell and I like the idea of saving the weight, especially way out at the end, thats a long moment of inertia.

Plans for a stock appearing fiberglass SA bumpers? You could save some serious weight in a very beneficial location........

 

And I'm still waiting for a decent exhaust system Sam...

And how about a real live fully functional front air dam? You'd better hire some help buddy. lol

 

I guess you could always drill a series of holes around the shaft to make a weak link crinkle zone. This way it would collapse and absorb some of the energy from a crash.

 

Very interesting... Pics of this? I thought about tucking the bumpers before. But never got around to attempting it. I never even thought people done this before on a 1st gen.

 

Good reply! Agreed

 

Those firemen either need a longer hose, or they need to worry less about scratching up their pretty truck and park closer.

Looked like they were forced too close to the vehicle by lack of hose reach.

 

Group buy Started:

https://www.rx7club.com/showthread.p...3#post10689503

 

I would be interested in a set for an SA bumper to FB chasy that way i dont have to make my own

 

If anyone has an SA shock bumper to take a couple measurements off of for me and maybe a couple of pictures, then I can most certainly try and accommodate something of such.

 

I would also be interested in a tucked set if you made one. I hate the way the stock bumper sticks out so far. Your part looks nice and the price is right