New Product: Front Lower Frame Brace
Race Car
Joined: Jan 2004
Posts: 3,860
Likes: 0
From: Charlotte, NC
I have stock everything up front and i see no unusual tire wear. scot doesnt either and he is all stock as well. we cord the tires on the inside edge unless we visit a track like Sears with a high speed carocell, and we have sligthly more outside edge tire wear, but its not much. mostly due to understeering.
the frame doesnt flex. all you need to do to prove this is to grab the outer part of the wheel and tires with a tie down and start to bind them down. the most force the tire will ever see on a street car is about 1 G, so there could be 1500lbs of force on that tire. take a look at all the components here. the LAST thing in the world that is going to flex is that part of the chassis. You can see by my wheel cam that there is little flexing going on by the tire as it loads and grips the road. However, it does provide some great protection for the underbelly from what i see.
mk
the frame doesnt flex. all you need to do to prove this is to grab the outer part of the wheel and tires with a tie down and start to bind them down. the most force the tire will ever see on a street car is about 1 G, so there could be 1500lbs of force on that tire. take a look at all the components here. the LAST thing in the world that is going to flex is that part of the chassis. You can see by my wheel cam that there is little flexing going on by the tire as it loads and grips the road. However, it does provide some great protection for the underbelly from what i see.
mk
I forgot to mention I freqently do Dukes of Hazzard style 2 wheels on the ground cornering, but never thought that would cause uneven tire wear.
Seriously though, the car flexes. I can offer indisputable proof of movement somewhere near the radiator. Not sure if this is evidence of the type of twisting that Carl speaks of.
I am having loose tie rods replaced this week - those are possible contributory culprits toward excessive tire wear. I am never lucky enough to have only one problem at a time.
My track buddies are able to get twice the tire wear as me. This must stop!
"see little flexing".... I don't know how anyone can visually see 1 degree of movement at a time. That is like measuring 3hp gain using a buttometer.
Race Car
Joined: Jan 2004
Posts: 3,860
Likes: 0
From: Charlotte, NC
mark, if the frame dosent flex - why did the factory add the brace to the top of the engine bay?? seems the engineers thought it flexed, take a look at the factory stock brace - its bent from flexing. i know this is at the top of the frame but for every action there is an equal and opposite one - if the top is going in then the bottom is twisting out etc.
Drifting
Joined: Dec 2003
Posts: 2,903
Likes: 3
From: an unnatural suburban habitat
These cars were designed with old technology 225/50 front tires, and the forces on the car from bigger stickier tires and stiff suspension today are probably double what the engineers saw in testing.
I think the bar is a good idea in tying the front of the lower control arms together to box that area. It probably keeps toe much more consistent when cornering, and I do notice less drama at the wheel in fast hard sweepers.
Obviously there is no good measurable data for this, it's just speculation at this point. You would need a chassis rig at a race shop to be able to get any data.
I think the bar is a good idea in tying the front of the lower control arms together to box that area. It probably keeps toe much more consistent when cornering, and I do notice less drama at the wheel in fast hard sweepers.
Obviously there is no good measurable data for this, it's just speculation at this point. You would need a chassis rig at a race shop to be able to get any data.
Drifting
Joined: Dec 2004
Posts: 2,235
Likes: 2
From: Atlanta
The cars definitely flex. Anyone who has put one on jackstands knows it. It you don't get the stands exactly equal you'll have trouble opening and closing the doors, that's a fact. I like this product a lot and if I was tracking my car it would definitely be installed. And yes a full cage makes a huge difference.
Thread Starter
Developer
Joined: Dec 2001
Posts: 7,005
Likes: 64
From: Horicon, WI
Kibort:
Ridiculous. Of course it does. Its a unibody car! Not a tube-framed car (and even they flex)
Test: Unbolt one end of the upper strut brace from across the engine. Jack up the RF tire, as if to change it. With the RF tire in the air, try to put the bolts back in the strut brace.
the frame doesnt flex.
Test: Unbolt one end of the upper strut brace from across the engine. Jack up the RF tire, as if to change it. With the RF tire in the air, try to put the bolts back in the strut brace.
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Joined: Jul 2001
Posts: 11,542
Likes: 4
From: Anaheim California
better test of flex is jack the car up using the front tiedown bracket right where Carl's bar attaches then put a jack stand under the front jack pad and let down the car. Then start raising the jack and note that the car bends as the jack begins to push up but see how far you must raise it BEFORE the jack stand on the jack pad is no longer touching the bottom of the car.... ALL "solid " things bend ..... I used to sit at my desk high in the old B of A headquarters and on a windy day watch as the open door to my office would swing back and forth 3-4 inches ...the door was not moving...the building was . Carl's race car may exhibit more than normal movement since the upper sheet metal triangulation to the firewall has been cut away....much like the stock upper "strut bar" cross brace that is stronger in tension than it is compression... they do contribute to the overall strength of the unibody "eggshell" .
. Carl's race car may exhibit more than normal movement since the upper sheet metal triangulation to the firewall has been cut away....much like the stock upper "strut bar" cross brace that is stronger in tension than it is compression... they do contribute to the overall strength of the unibody "eggshell" .
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Joined: Jul 2001
Posts: 6,562
Likes: 114
From: New York
Whaaa, !! Isn't anyone going to comment on this? Since the thread went on for 2 pages and no one reported any dire belt problems I'm sure there is a simple explanation.
Drifting
Joined: Dec 2003
Posts: 2,903
Likes: 3
From: an unnatural suburban habitat
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