KyleT

you could possibly support the brush guard from the top side of the bumper with some flat stock to keep it from bending back as bad.

around here, they are known as damage multipliers. how many times have you seen a relatively small crash yield lots of front end damage when a grill guard pushed back into the lights, hood, fenders ect...

slosurfer

dam! you beat me to it.

HuskyRunner

The only issue I've had with mine was coming down a short, steep hill into an uphill, I hit the ground with the mounting tabs on the bottom. Eye balling it at the time, I MIGHT have been okay with out it, but it would have been relly close. I like mine, but it's coming off when the body lift goes on.

wjwerdna

all right, now I have the proof, however I over engineering the bullbar in use for the tests, if yours is this strong, then its almost worth it...

assumptions:

• vehicle starting speed = 15-20 mph
• vehicle speed upon reaction, braking, and at beginning of impact = 10mph
• vehicle weight = 3000lbs

bullbar dimensions:

• height = roughly 24"
• width = 42"
• distance between uprights = 20"
• upright material = 1/4" cold rolled steel (honestly, whos isnt stamped?)
• bar material = 1"OD .125 Wall CRS

so what is the force in an impact at 10 mph you may ask?

assume, you move a total of 12" during the impact

10 mph = 14.7 ft/s
avg velocity over this 12" of deceleration is 8ft/s
distance = velocity x time
time = 12 in / 8ft/s
time = .125 (.1 to .133 is an acceptable time frame during impact)
assume at the end of the impact you are still rolling forward a bit ... 1ft/s

so you go from 14.7 to 1 ft/s in .125 s...

13.7ft/s / .125s = 109.6 ft/s/s = 3.41 G

then take 3.41 G x 3000# vehicle ... gives you a force of 10230 lbs during impact at 10 mph, after braking from 20 or so

this is sort of a linear relationship

20mph at beginning of impact over a longer distance, but greater avg V = 20100 lbs

40 mph = 42000 lbs

.............................
so, where the hey am I going with this you may ask?

well, I'm going all the way..

max stress of steel as you all know is around 34000 psi for your most generic number

10 mph crash results in 90,000 psi, at the weakest point, resulting in deformation of your heavily-built steel bullbar, that weighs quite a bit

20 mph crash results in a max stress of 1,810,000 psi

40 mph = about 4 million psi
........................

also ... 10 mph crash results in the top most part of your bullbar to have a net displacement of 1.5 inches

20 mph = 3 inches

40 mph = 6 inches
............................

heres a little backup so you dont think this is all BS





enjoy.... that was way too much work, but I think it gets the point across...

remember, if your vehicle weighs more than 3000 lbs.. say more like 4000-4400 you'd have more force involved in the impact... like 15000 lbs

PS: screen shots taken using 40mph impact, all scenarios look the same, just different numbers, all fail at same spot, at move the most at one spot

wjwerdna

lol, don't worry, I did all this in good fun, i really wished I'd built the model to more closely resemble the strengths of most guards, not of a crazy strong one

4x4Lamm

How about this? When I had my 92 4Runner I had a stock Toyota brushguard and I rear-ended a Corsica at less than 30 MPH. It Caused damage to the fenders, hood, radiator support, hood latch, headlights and corner lights that would have never happened without it, PLAIN AS DAY.

Then I was dumb still at the time (and 17 like yourself) and I had my insurance pay for another one, this time GSP. What I got was $350 worth of exhaust tubing and 1/8" plate barely welded togeather with powdercoating not worth a dime. It did nothing but get in the way of everything, it shook like a polaroid picture and got hung up down low a few times. I then got smart and sold it because I wanted my truck to work as good as it looked.

They look cool, they are cheap, they do not work well. The best thing mine ever did was hold a pair of lights.

Lamm

Kyle95sr5

HAhaah, thanks for goin all out for his Andrew. Not really sure what im lookin at there but thanks anyway. Guess I need to read into it a little more.

Okay Lamm, that is your situation. Im sorry it worked out that way. My brushguard saved my bumper, grill headlights, and possibly my hood. Like was said before, there are too many variables to determine whether or not a brushguard would do more or less damage in event of an accident. My Manik is a little more stout them some exhaust tubing though

4x4Lamm

Remember though, the one that caused me so much damage in my wreck was a TOYOTA factory model. It's OK if you want one, it's your vehicle.

I think what pushes peoples buttons is when anyone makes claims about their vehicles or its mods that really are unfounded. I don't claim that my TJM can shield me from all damage up to 45 MPH, ect.

I equate this whole debate to the seatbelt debate. Yes, sometimes it will do more harm than good but if you are dumb enough to play those odds, stay away from Vegas.

Lamm

itsmeagain5789

i say we just send this to mythbusters and let them crack the case