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I don't understand your point unless you're referring to the comment about the D4's ECB bar which I checked yesterday to find 2 long slots in each of its vertical brackets which would provide some force relief on impact, but still no head-on crumple capability unless the manufacturer expects the vertical brackets to distort sideways.
Not entirely true. People keep speculating that this & that would be illegal without actually understanding the requirements.Quote:
Originally Posted by chaybra
Plus, as a point of interest, the crash bar under the bumper cover is bolted directly to the monocoque front bar.
The Land Rover winch mount, bolts directly to the same monocoque front, this is also legal, and very heavy!
The crash sensor is located above the transmission tunnel & senses forces in all directions. A crash would produce the same force regardless of winch bar or standard crash bar.
Don't take note of manufacturers and others that speculate 9k for some crash test, the aim is to keep competition out of the market.
A positive approach is needed if this is to become real.
Bull bars need to be approved by a government appointed engineer (VASS in Victoria) I have approached many of them and all gave me the same response, they will only accept a report stating that the deceleration speeds are within a tolerance of the factory impact bumper speeds.Quote:
Originally Posted by diesel
I have then independently contacted several of the facilities that conduct these tests. 2 impacts must be done at each of the high and low speed tests, one with the original bumper (to determine the base line) and one with the new bull bar. excluding the price of 2 factory impact bumpers and the bull bars, they want 9k. This is not a speculation, this is a quote.
The price of running the tests is why, with manufactures that would agree to deveolping, want a large deposit without even designing from about 10 people to cover the costs of developing.
I am very very keen to have bullbars made for the L322, it may just have to wait a bit until more and more people start to use them off road and show the numbers are there.
this may be a stupid question:
Why can't a bar mount directly to the existing steel crash bar behind the plastic skin? Deformation would then match the factory bar.
I assume all of the solutions involve removal of the crash bar but why not use it? It is very solid, runs within an inch of the corners. The factory wrap around bars bolt directly to the crash bar without any deformation parts - which is why the factory bar is so solid, IMO it just lacks headlight protection.
I considered that as an option to be assessed once the bull-bar has been acquired and the plastic bumper has been removed. In some ways leaving the reinforcement bar in-situ provides more flexibility in mount options if the distance between bull-bar mounts doesn't match almost exactly with the mounts for the reinforcement bar but the bull-bar may then protrude too far forwards. By my reckoning the ARB crush-cans would allow the bull-bar to sit closer to the body but could be too close anyway. I need to temporarily remove the plastic bumper for some initial measurements but that task will now have to wait a while as harvest madness is about to start. Retaining the reinforcement bar should avoid any insurance arguments regarding possible early or late triggering of air-bags.
I too have attempted to go down this path, however...an approval from an engineer would still be required because it technically still modifies the pedestrian impact zone. modification to the bumper itself will still require modification if you wanted a winch.Quote:
Originally Posted by harlie
This sounded good and promising to me, All I had to do was find a VASS certified engineer to see the point that it was impossible for this to affect the airbag sensors...but no, every single one (im talkin like 20 ppl I called) would not touch it with a 10ft pole unless it had the report from the crash tests.
Alot of effort to go to to get a metal bumper with no winch or decent headlight protection still.
Some years ago, around 2004 I fitted a TD5 into soft dash LSE Classic.
I made up some aluminium extras, ie roof rack, ectra tanks (wing)-one water and 1 fuel,PLUS a bullbar. There were no "commercial/approved" bars available then for a classic with driver and passenger airbags.
I used the centre section of a (blush) Landcruiser and made up each end Made it to mount to the original crush cans that were on the car.
also made a winch mount that bolted to the chassis, NOT the bar.
Anyhow, when I had the vehicle modification inspection done, the engineer passed/approved the engine conversion, gearbox conversion, wing tanks, 7 seat edition, AND the bar, saying that as I used the original crush cans, he deemed it ok.
All items were included on the paperwork and mod plate.
I included all these extras/info in insurance application and they were all covered up to when I sold the car to WA, 2013.
Maybe just lucky?
No Don, not lucky at all. As I said in a previous post on this subject, if you are doing a one off for own use, and you do your engineering in line with the rules, your engineer can pass it without the crash test rubbish that keeps getting sprouted. The crash test issue is for commercial applications where a 3rd party manufactures the product and on sells it for a profit and possibly makes many copies. It has nothing to do with the profit component but that fact that you have brought a 3rd party liability and insurance issue into the equation. Also, if there are many copies of the one design out there, the likelihood of some kind of crash or accident is exponentially higher with each copy that goes out there and thus, the insurers try to make sure the liability and need for them to pay out is as low as possible.Quote:
Originally Posted by donrover0
Now, this has caused a reticence in a lot of engineers to swim against the tide as they also then assume the liability but they do have the authority to certify a one off if done correctly. The "crash test" defence is simply a ruse to get you to go away. I have a lot of documentation to prove this.
Grant
A point to ponder: who says that all L322s are programmed to trigger their air-bags on the same impact severity? These vehicles have undergone several major changes and have been under the control of several different owners. Crash testing a bar on 1 particular model doesn't prove that the same result will occur on another model. Even if the same accelerometers are fitted to the whole range, programming will undoubtedly be different and may have different trigger levels. The air-bag modules from pre-MY10 will not fit or work on a MY10+ due to using different canbus specifications and I suspect pre-MY07 are different to MY07-MY09, but perhaps not.
I doubt that any bull-bar manufacturer would be interested in building a bar if they knew of these differences and could not ascertain that LR's impact specifications were identical across the range.
This is exactly right, no crash test is required as a couple of us have pointed out.Quote:
Originally Posted by RR44TDV8
The bottom line is engineers want to see that you have performed the correct calculations for your modification. You cannot just 'guess' the gauge of steel being used with folds & joins that just look 'nice'...
You have to prove your knowledge, show how the design will handle the kinetic energy in the event of a collision for example.
Finite Element Analysis can be done with CAD software, ARB use this approach, as do others.
Remember I said the Land Rover winch attachment attaches to the front of the bumper, and the front subframe. It's heavy & made of steel... :)