BMR stuff is crap ... now I have proof!
#101
Re: BMR stuff is crap ... now I have proof!
I would agree.
Don't buy a cheap part expecting it to work and last like a better engineered and designed part.
The better parts typically are more expensive.
The unfortunate thing is, folks buy according to their wallet, instead of application.
Guilty as charged ...
Don't buy a cheap part expecting it to work and last like a better engineered and designed part.
The better parts typically are more expensive.
The unfortunate thing is, folks buy according to their wallet, instead of application.
Guilty as charged ...
#102
10 Second Club
iTrader: (15)
Join Date: Nov 2001
Location: St. Michael, MN.
Posts: 4,519
Likes: 0
Received 0 Likes
on
0 Posts
Re: BMR stuff is crap ... now I have proof!
I would agree.
Don't buy a cheap part expecting it to work and last like a better engineered and designed part.
The better parts typically are more expensive.
The unfortunate thing is, folks buy according to their wallet, instead of application.
Guilty as charged ...
Don't buy a cheap part expecting it to work and last like a better engineered and designed part.
The better parts typically are more expensive.
The unfortunate thing is, folks buy according to their wallet, instead of application.
Guilty as charged ...
#104
TECH Junkie
Join Date: Nov 2001
Location: Chi-Town
Posts: 3,029
Likes: 0
Received 0 Likes
on
0 Posts
Re: BMR stuff is crap ... now I have proof!
i drove my car on a road track a lot harder than i would ever see on the street i thought my tires were gonna come off my rims
#106
On The Tree
Join Date: Dec 2002
Location: Central FL
Posts: 112
Likes: 0
Received 0 Likes
on
0 Posts
Re: BMR stuff is crap ... now I have proof!
Two things - one comment, one question.
First, as someone who works as an engineer at GM's proving grounds, I can tell you stuff is tested way beyond what an average car will see on the street. There are countless tracks and roads out there designed to do nothing but beat the tar out of cars in every way imaginable. I'm not even in development (yet), but you should see what I get to do to some of those cars as part of my work as an engineer - and that's coming from someone with a circle track and road course karting background.
Secondly, I'm not entirely convinced that these failures wouldn't happen with any poly/poly bushing rear suspension piece. The way our rear axles move, smooth pavement or not, something has to give. When you take out the rubber bushings and slap rock hard poly in there, either the sheet metal on the car has to give or the metal surrounding the bushing has to. Going back to my experience in the OEM world, my money's on the aftermarket part.
First, as someone who works as an engineer at GM's proving grounds, I can tell you stuff is tested way beyond what an average car will see on the street. There are countless tracks and roads out there designed to do nothing but beat the tar out of cars in every way imaginable. I'm not even in development (yet), but you should see what I get to do to some of those cars as part of my work as an engineer - and that's coming from someone with a circle track and road course karting background.
Secondly, I'm not entirely convinced that these failures wouldn't happen with any poly/poly bushing rear suspension piece. The way our rear axles move, smooth pavement or not, something has to give. When you take out the rubber bushings and slap rock hard poly in there, either the sheet metal on the car has to give or the metal surrounding the bushing has to. Going back to my experience in the OEM world, my money's on the aftermarket part.
#107
Re: BMR stuff is crap ... now I have proof!
I'm not sure I agree with the second part.
If something must move, even rod ends wouldn't do the trick. And then it wouldn't just be on the panhard, it would include all suspension components that are replaced with rod ends.
If something must move, even rod ends wouldn't do the trick. And then it wouldn't just be on the panhard, it would include all suspension components that are replaced with rod ends.
#108
TECH Senior Member
iTrader: (4)
Re: BMR stuff is crap ... now I have proof!
I'm starting to remember why I don't like Poly bushings (I never really liked them, but I'm seeing more "results").
http://corner-carvers.com/forums/sho...threadid=11858
Interesting....
In all fairness, I posted this because it is a "Non-BMR failure". Someone in here said something about everyone having failures and that is a reasonable statement. So, I tossed this info up to help illustrate that point. And this failure was from a well respected suspension company. This won't change the fact that I don't like BMR's new or old designs and I find the quality of their rod ends to be inferior to almost everyone. But, it does show that "stuff happens" to other manufacturers as well...
It may be the beginning of a trend towards "why we shouldn't use poly bushings in places they don't belong (more than 1 axis of rotation).
My thoughts...
http://corner-carvers.com/forums/sho...threadid=11858
Interesting....
In all fairness, I posted this because it is a "Non-BMR failure". Someone in here said something about everyone having failures and that is a reasonable statement. So, I tossed this info up to help illustrate that point. And this failure was from a well respected suspension company. This won't change the fact that I don't like BMR's new or old designs and I find the quality of their rod ends to be inferior to almost everyone. But, it does show that "stuff happens" to other manufacturers as well...
It may be the beginning of a trend towards "why we shouldn't use poly bushings in places they don't belong (more than 1 axis of rotation).
My thoughts...
I agree completely with this statement:
Secondly, I'm not entirely convinced that these failures wouldn't happen with any poly/poly bushing rear suspension piece. The way our rear axles move, smooth pavement or not, something has to give. When you take out the rubber bushings and slap rock hard poly in there, either the sheet metal on the car has to give or the metal surrounding the bushing has to. Going back to my experience in the OEM world, my money's on the aftermarket part.
1.Destroy the bushing.
2.Break the housing the bushing is in.
3.Tear the sheetmetal that the control arm mounts to.
4.Break the control arm bolt (fatigue cycles).
The suspension is designed to move in various planes of motion, if something restricts this motion (other than the bumpstops or the limits of shock travel), that part will be subjected to tremendous loads. The only way to help this situation is to reduce those loads. If you don't take steps to reduce the loads, the suspension will eventually do it for you (something will break). I think we are starting to see this first hand. Everything has a fatigue life, we are just starting to see what that lifespan actually is.
However, I don't agree with this statement:
If something must move, even rod ends wouldn't do the trick. And then it wouldn't just be on the panhard, it would include all suspension components that are replaced with rod ends.
It's getting late and I hope this answer makes sense....I'll re-read it tomorrow.
Keep the shiny side up!
#109
Re: BMR stuff is crap ... now I have proof!
I think sometimes we forget good ole momentum.
If something is rock solid, then forces have to go beyond sheer of the weakest part.
If something has slop, there are still the same forces applied, however there is now shock involved.
With bushings deflecting and with back and forth forces applied, like during a spin, the shock forces have to be tremendous.
If something is rock solid, then forces have to go beyond sheer of the weakest part.
If something has slop, there are still the same forces applied, however there is now shock involved.
With bushings deflecting and with back and forth forces applied, like during a spin, the shock forces have to be tremendous.
#111
On The Tree
Join Date: Dec 2002
Location: Central FL
Posts: 112
Likes: 0
Received 0 Likes
on
0 Posts
Re: BMR stuff is crap ... now I have proof!
Thanks for clarifying what I was trying to say Trackbird. I think a lot of poly/ploy fans forget the fact that unless your car is doing nothing but going in a straight line on level pavement (i.e. a drag strip) that there are twisting forces on bushings of both the LCA's and the PHB.
I totally agree with your comments on rod ends. As someone who grew up around circle tracks and midgets/sprint cars, I know how expensive a good rod end is. The only rod ends I'd trust in a hard-driven car are more expensive than I'd care to spend on my street car. I'm sure I don't have to tell you how expensive good rod ends are though...
I totally agree with your comments on rod ends. As someone who grew up around circle tracks and midgets/sprint cars, I know how expensive a good rod end is. The only rod ends I'd trust in a hard-driven car are more expensive than I'd care to spend on my street car. I'm sure I don't have to tell you how expensive good rod ends are though...
#113
Re: BMR stuff is crap ... now I have proof!
there are twisting forces on bushings of both the LCA's and the PHB.
The only binding from twist would occur if the articulation was so severe that the rod end "housing" came in contact with the mount, correct?
#115
Sam Stranos makes a very nice PHB. It is chromoly steel so it is light yet strong. It has adjustable heim joints on each end. I have this in my car and hit the road course fun days several times a year. It is very solid and I bought it new for $169.00
.
.
#116
TECH Resident
Join Date: Jan 2003
Location: South Alabama
Posts: 937
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by mbraun
Sam Stranos makes a very nice PHB. It is chromoly steel so it is light yet strong. It has adjustable heim joints on each end. I have this in my car and hit the road course fun days several times a year. It is very solid and I bought it new for $169.00
.
.