Roll Bars-- Why...Why not...How Big.....

[Jon Scully]

Hello Group,

I have a 71 blazer 4x4, I will use it as my summer daily driver, and some light offroading-- camp roads here and there etc:

So-- My question is, for safety and structure is a roll bar necessary? I am not a big fan of how most of them look, and would rather not put holes through my cab. But am open to discussion on the rationale and 'girth' required for my use....

What do you guys think? Have you got any pics of ones that look good for the average driver (i.e non- 4by junkies Love the crazy 4x4's but, just not what I am going for with my toy lol )

Thanks again

Jon
Thunder Bay ON Canada
__________________________
98 police interceptor
71 blazer 4x4
87 300zx

[SeventyOne]

If you're not going to run a roll cage or even just a roll bar just know the limits of the rig and don't get into anything that will injure yourself, your family, or other people. If you roll your rig with NO protection your about as good as dead imho.

[Mike C]

My Smittybuilt bar was 2". I added the weld in cage kit, also 2" DOM .120 wall. I had to cut the cage legs out when I put the soft top on as it does not have as much interior clearance as the hard top. I will be redoing the cage in the future.

About 15 years ago, a guy was pulling a 16' trailer down the road here when some kids in a Camaro pulled out not just in front of him, but across his front. He jumped the car, turning the Blazer onto it's side and roof as it went down the road. Him and is son walked away because of the roll bar.

I don't worry much about my really mild offroading compared to what might happen ON the road at high speed.

[edit:] It also stiffens the truck up a bunch. I was always surprised how much my passenger door bound up when I took the hard top off. The cage helps control that quite well, but not the bar.

[Gibber1967]

I rolled an all original 1972 CST Blazer a few years back with out a rollbar. Had 4 people in it and we walked away with 12 stitches and a 1st degree shoulder seperation between the 4 of us. I was literally going about 5 MPH on a frozen road in the winter, into the ditch and then onto the roof. It was a slow roll but the roof exploded and the windshield frame was pushed down flat. Of course when the tow truck arrived we had to roll it back over on the undamaged side. I did manage to drive it home.

Part of the repairs on that one was adding a roll bar. I was looking for a clean original truck, and this one had a dent in every panel so I got rid of it after that.

The Blazer I just bought does not have a rollbar, but I do intend to put one in. I'm not driving it in the winter at this point. If you are hauling your family around in it and planning to do some 4 wheelin' I would say it is a must.

Gibber

[BIGBLU 72]

i have a factory style bar in mine and just the cool factor of the looks that it brings is amazing! idk how much it will save me in a roll over tho? i have seen one of these blazers picked up and shook by a crusher crane (i dnt want to talk about why Ive seen this) but was really impressed with the strength of the top

[Jon Scully]

Thanks for the info guys--I am still weighing my options....but am leaning towards a modest bar---

What would be really cool would be some pics!!!!-- Specifically-- how they mount, and how well they fit with the tops - hard and soft (I think my soft top is a STC)....

Also-- @BIGBLUE-- are there any factory bars....I did not think they had factory bars on these trucks? AS usual I could be wrong lol

Thanks

jon

[Jon Scully]

About the fiberglass top--- I did not realize thye would be so fragile....My worries were more concerned with the summer topless driving....you do have me thinking more tho

[BIGBLU 72]

I was told mine was a dealer add on deal? fits perfect under the top!

[Mike C]

That is the Smittybuilt bar. I added the cage conversion to mine but as mentioned before, had to remove the front because the STC top I have didn't have sufficient clearance at the windshield frame.

The bar part clears both the STC top and the factory hardtop with ease. The bar rear legs attach behind the rear wheelwells using plates like a unitbody car. I am going to build a full-coverage cage for mine sometime here pretty quick. I've got 80' of 2" DOM waiting for me to have the time.

And I want some practice on cheaper tube, so will cage my A1 first with 1 5/8" as a learning tool!

[7D2N]

I picked this one up cheap and with a little modification and re-chrome this is what I ended up with. How well it will do it's job not sure and I hope I don't find out but I like the way it looks.

[Critter]

Keep in mind there is a difference between a true "roll bar" and the things that came installed from the dealers, I have heard them called a "sport bar". A true roll bar will go through the body and attach to the frame in AT LEAST 4 points, preferably more. The sport bar like most of us have is simply bolted to the sheet metal which is fairly weak. A sport bar will definitely be better than nothing in the event of a roll, but don't fool yourself into thinking that it will do what a true roll bar will do like in a race car, rock crawler etc. In the event of a roll, the initial impact will probably be lessened, but a split second later the sheet metal mounting area will most likely rip away. Of course this all depends on the dynamics of the crash. The problem I have is I personally love the way the sport bars look in our blazers so I plan to keep it. Heres a pic of mine with the dealer installed bar just for the heck of it before I tore the Blazer down.

[joemacho]

yup i like my roll bar also hopefully one day i ll have mine redipped in chrome...

[Manuel Raptor]

Here is a Picture of mine. I actually want to extend it to a Family cage or Roll Bar all the way to the back.

[Jon Scully]

nice trucks Guys!

To be clear then.... It will not do much unless you cut up the cab and attach to the frame?

I get the concept- "That if it attaches to the floor is is only as good as the floor is"

This has given me lots to think about and a couple of questions--

1) If the roll bar mounts to the frame how do you seal it where it comes thu the body? What about suspension movement?
2) What kind of load do you think the 'beauty' floor mounted bars can handle....Could thye at least keeo your head off the rocks in a typical roll over (low speed? vs higher speeds?)

Lots to ponder still ....and many more pictures to see==
Thanks and lets keep this thread going-- I am sure I am not the only one with K5 specific roll bar issues....

[Burt4x4]

Frame mounting is not completely nessisary if the cage/roll bar is made properly. Does it make it stronger..sure but it doesn't have too be too save you. The body has crossmembers under it and using thease "stronger" points gives you a better than "just bolted too sheet metal" concept. Plus the overall design can keep it from crushing or "punching" thru the body in a rollover. Our Blazer tubs are perrty strong, without the rust ofcorse hahaha

Most frame mounted cages "sandwich" the body and don't "go thru" the body..some do but not all...really depends on what your using the rig for. When you attach your cage too the frame it is going too stiffin your off-road ride by HUGE amounts = no more frame flex only suspension flex..some say that is better..I'm not sold on that. I love my flexy flex and have no intentions on frame mounting my cage.
anyway my .02c
Burt

[swyfor5]

Hear ya loud and clear on the flexy point Burt! My suspension does not flex enough as it is, don't want to stiffen it up any more. I do love the look of the full cages though, and that is the way I am going in the future!

[Critter]

Originally Posted by Jon Scully

nice trucks Guys!

To be clear then.... It will not do much unless you cut up the cab and attach to the frame?

I get the concept- "That if it attaches to the floor is is only as good as the floor is"

This has given me lots to think about and a couple of questions--

1) If the roll bar mounts to the frame how do you seal it where it comes thu the body? What about suspension movement?
2) What kind of load do you think the 'beauty' floor mounted bars can handle....Could thye at least keeo your head off the rocks in a typical roll over (low speed? vs higher speeds?)

Lots to ponder still ....and many more pictures to see==
Thanks and lets keep this thread going-- I am sure I am not the only one with K5 specific roll bar issues....

Originally Posted by Burt4x4

Frame mounting is not completely nessisary if the cage/roll bar is made properly. Does it make it stronger..sure but it doesn't have too be too save you. The body has crossmembers under it and using thease "stronger" points gives you a better than "just bolted too sheet metal" concept. Plus the overall design can keep it from crushing or "punching" thru the body in a rollover. Our Blazer tubs are perrty strong, without the rust ofcorse hahaha

Most frame mounted cages "sandwich" the body and don't "go thru" the body..some do but not all...really depends on what your using the rig for. When you attach your cage too the frame it is going too stiffin your off-road ride by HUGE amounts = no more frame flex only suspension flex..some say that is better..I'm not sold on that. I love my flexy flex and have no intentions on frame mounting my cage.
anyway my .02c
Burt

Burt has a lot of wise info here. The safest way is to go down to the frame, but in the real world that might not be realistic either from an offroad flex stand point, or for on-road comfort. Personally I have considered makeing a more substantial "roll bar" or "family cage" by building something with 6 mounting points. Those points would be right in the area of the main body mounts ON TOP of the sheetmetal. Maybe I could get the actual body mount bolts to go through the roll bar mounting plates. That way everything would be pretty strong, attached right at a strong frame point, but still allow some flex thanks to the body mounts. I have a degree in mechanical engineeing so like most of my long winded ideas, its just that, an idea that I haven't put into effect yet...typical engineer.

[HI OFCR]

Originally Posted by 7D2N

I picked this one up cheap and with a little modification and re-chrome this is what I ended up with. How well it will do it's job not sure and I hope I don't find out but I like the way it looks.

7D2N, Yours is almost identical to mine. I was told it is for a older Dodge ram pickup. I also like the way it looks with the larger bars. .