T-Bar Delete with Roll Center correction and Rod ends. COMPLETE!
07-18-2013, 11:37 AM
#107
Burning Brakes
I will take some better pictures this weekend, my icamera lens is messed up.
It is bent in a pretty even arch with a small kink on the top near the center.
I have not heard from Bruce.
It is bent in a pretty even arch with a small kink on the top near the center.
I have not heard from Bruce.
07-20-2013, 12:41 PM
#108
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Someone alerted me to this. That is truly a lot of bend. That is a 2x2 bar I make for the the "lighter" racers. I'm not sure why, or can remember the details of why I sent you out that bar instead of the thicker one. I made a 2x3 (longer in the dimension that would stop that sag) for normal weight cars. (pictured below) The 2x3 bar should be the Exact dimensions, thicknesses and shape as the later Kokeln piece. If you would like, I will try my hardest to make a 2X3 as fast as I can. The 2x3 will hold if you want it replaced. It looks like the swing arms are still good, so It will be a little faster if I only have to make the main bar.
Was there anything specific that happened when you noticed this? Or was it more of a point where it just wouldn't handle well anymore and you were surprised to see the bend? Edit: I saw the answers in one of your posts.
none the less. Please email me at bkarger2010@gmail.com
here are the thicker units;
Was there anything specific that happened when you noticed this? Or was it more of a point where it just wouldn't handle well anymore and you were surprised to see the bend? Edit: I saw the answers in one of your posts.
none the less. Please email me at bkarger2010@gmail.com
here are the thicker units;
Last edited by 95ONE; 07-20-2013 at 01:48 PM.
07-20-2013, 12:47 PM
#109
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And a question for Bruce:
Does the center of the heim location line up with the hole at the inside trailing arm mounting point (same plane)? Could there be a goofy angle that the factory could be running that might make a difference? It seems like there is twist introduced between the wheel and the inside trailing arm attachment location.
Does the center of the heim location line up with the hole at the inside trailing arm mounting point (same plane)? Could there be a goofy angle that the factory could be running that might make a difference? It seems like there is twist introduced between the wheel and the inside trailing arm attachment location.
No. Not straight through. there is an angle which I kept strictly stock.
07-20-2013, 12:54 PM
#110
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And a question for Bruce:
Does the center of the heim location line up with the hole at the inside trailing arm mounting point (same plane)? Could there be a goofy angle that the factory could be running that might make a difference? It seems like there is twist introduced between the wheel and the inside trailing arm attachment location.
Does the center of the heim location line up with the hole at the inside trailing arm mounting point (same plane)? Could there be a goofy angle that the factory could be running that might make a difference? It seems like there is twist introduced between the wheel and the inside trailing arm attachment location.
Wanting to hear, or read further if TONY's from vision had tabs on his newest piece? I've seen pics of a few "kokeln" bars .. maybe they weren't. But there weren't any tabs on those pics. Only tabs on the one on their website. But i never saw tabs on any others from Kokeln after that. The tabs were a nightmare to try to add and seemed a bit overkill. I might be proved wrong here, but maybe the bolts just backed out of the side mounts? Reading on.
Last edited by 95ONE; 07-20-2013 at 01:49 PM.
07-20-2013, 12:57 PM
#111
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It was for him. And a couple others. I'm still reading and trying to figure out what is happening, or has happened.
07-20-2013, 01:05 PM
#112
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Looking at the pictures of the bent part again, it appears that the bend is in the vertical plane - e.g. the center of the square tube was pushed downward; as opposed to forward or rearward.
To make a bend in this direction, the inner portion of the control arms would have to be pushing down.
Because you're using a coil-over system (since obviously the torsion bars are gone), the weight of the car's chassis (the sprung weight) is pushing down on the shock/spring, which is then pushing down on the control arm about half way between the contact patch and the pivot point.
If North Coast Cab is using 1000 lb springs, and presumably stiff dampers to go with them, it's quite likely that a large bump in the road, while cornering right, caused the rear wheel to move up suddenly.
Because of the shock damping and heavy spring, the shock didn't compress much, and because of Newton's law about overcoming inertia, the car's sprung weight stayed pretty still. So, the upward motion of the wheel caused the control arm to pivot around the lower shock mount, which put a downward force on the inner control arm mount, thus bending the bar down.
The short answer is this: energy from bumps has to go somewhere... in this particular instance, the force needed to bend the bar was less than the force needed to compress the shock/spring.
To make a bend in this direction, the inner portion of the control arms would have to be pushing down.
Because you're using a coil-over system (since obviously the torsion bars are gone), the weight of the car's chassis (the sprung weight) is pushing down on the shock/spring, which is then pushing down on the control arm about half way between the contact patch and the pivot point.
If North Coast Cab is using 1000 lb springs, and presumably stiff dampers to go with them, it's quite likely that a large bump in the road, while cornering right, caused the rear wheel to move up suddenly.
Because of the shock damping and heavy spring, the shock didn't compress much, and because of Newton's law about overcoming inertia, the car's sprung weight stayed pretty still. So, the upward motion of the wheel caused the control arm to pivot around the lower shock mount, which put a downward force on the inner control arm mount, thus bending the bar down.
The short answer is this: energy from bumps has to go somewhere... in this particular instance, the force needed to bend the bar was less than the force needed to compress the shock/spring.
Last edited by 95ONE; 07-20-2013 at 07:06 PM.
07-20-2013, 01:34 PM
#113
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What spring rates are you running, and do you know if you have the 2x3" inch center bar, (taller) or the 2x2 like NorthCoastCabs is running?
07-20-2013, 01:35 PM
#114
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Thanks for coming into this thread Bruce. Lets see what we can make happen. Thus far, it's just the one unit that has had issues. Sounds like the lighter ones will need some modifications. Btw...which unit does Eric have?
btw (2) in your opinion, what apart from weight savings, is the main advantage of these units?
btw (2) in your opinion, what apart from weight savings, is the main advantage of these units?
07-20-2013, 01:37 PM
#115
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07-20-2013, 01:44 PM
#116
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Thanks for coming into this thread Bruce. Lets see what we can make happen. Thus far, it's just the one unit that has had issues. Sounds like the lighter ones will need some modifications. Btw...which unit does Eric have?
btw (2) in your opinion, what apart from weight savings, is the main advantage of these units?
btw (2) in your opinion, what apart from weight savings, is the main advantage of these units?
the huge advantage is the spherical bushing at the spring plate for consistent handling properties. (no longer slop in suspension alignments under load) And for the raised mounting point to help correct geometry for the lowered cars. which should help in all handling characteristics including better acceleration out of corners.
07-20-2013, 04:58 PM
#118
Burning Brakes
My car weighs 2650lbs and puts about 190HP to the wheels. It has the 2x2 center bar.
During qualifying it started to feel a little squirmy in the rear. Within a lap it felt very squirmy and so came in to the pits. Car had -9d camber on both sides. I'm sure once it started to go every bump worsened the issue.
Thanks for the detailed reply's.
During qualifying it started to feel a little squirmy in the rear. Within a lap it felt very squirmy and so came in to the pits. Car had -9d camber on both sides. I'm sure once it started to go every bump worsened the issue.
Thanks for the detailed reply's.
07-20-2013, 07:04 PM
#119
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Chrenan, I can only go by what MAX energy has said. He has a lot of use on this size with very high spring rates. He is an aggressive driver with no problems on the bar yet. The 2x3 has, of course, 50% more steel the full length of the bar, in the direction of which NorthCoastCabs bent. I was proven wrong on the 2x2, but the 2X3's are quite stout. I'm happy only in the way that it broke. Slowly and with notice. Also that the welds haven proven stronger than the material. I did the 2X2's to save weight, and only tried to sell these to cars the weighed in close to 2500lbs. Sadly, I didn't foresee the 1000lb spring rate issue. I'm certain that the 2x2 is just too small for the larger spring rates and need to be replaced.
I'm also pretty sure north Coast Cabs rides those curbs pretty hard, but I WANT him to and for everyone to be able to with full confidence. I'm fairly certain that the 2x3 box tube is the fix for any issues like this.
Chrenan, the design you have Is every bit the strength of the Kokeln piece since the box tube and material type should be an exact duplicate of the Kokeln piece. Even in light of NorthCoast's issues, I still suggest installing your piece. If yours bends or breaks, Or any others, I will do everything I can to get it replaced free of charge as quickly as I can.
I'm also pretty sure north Coast Cabs rides those curbs pretty hard, but I WANT him to and for everyone to be able to with full confidence. I'm fairly certain that the 2x3 box tube is the fix for any issues like this.
Chrenan, the design you have Is every bit the strength of the Kokeln piece since the box tube and material type should be an exact duplicate of the Kokeln piece. Even in light of NorthCoast's issues, I still suggest installing your piece. If yours bends or breaks, Or any others, I will do everything I can to get it replaced free of charge as quickly as I can.
Last edited by 95ONE; 07-21-2013 at 10:35 PM.