New Product: Front Lower Frame Brace
#16
Chronic Tool Dropper
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I like it!
Consider it an anti-roll bar for the outside frame rail, in the longitudinal axis. In this application, you are sharing the torsional stiffness of the relatively-unloaded inside frame rail with the more heavily loaded outside rail. Plus it's relatively easy to remove for access if needed.
Carl, did you give thought to using just a straight section of box tube with holes and spacers for the bolt, no adjustability? Just curious.
Consider it an anti-roll bar for the outside frame rail, in the longitudinal axis. In this application, you are sharing the torsional stiffness of the relatively-unloaded inside frame rail with the more heavily loaded outside rail. Plus it's relatively easy to remove for access if needed.
Carl, did you give thought to using just a straight section of box tube with holes and spacers for the bolt, no adjustability? Just curious.
#17
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I did consider box tubing, but some way or another the ends had to get collapsed to slide under the head of a mounting bolt. By the time I was there, the round chrome-moly came up as a better design, plus it gave us infinate adjustability as to length where a series of holes did not.
My experience with a series of mounting bolt holes is not only would it be weaker, but Murphy's Law dictates that none of them would be the right distance apart anyway. That's usually the way it goes.
My experience with a series of mounting bolt holes is not only would it be weaker, but Murphy's Law dictates that none of them would be the right distance apart anyway. That's usually the way it goes.
#19
Drifting
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carl, im interested to hear that you added camber just by hand tightening the bar, are you talking a quarter of a degree per wheel? have you noticed any differences when driving? looks lovely btw and very lite!
#20
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That bar would probably have saved my oilpan when I hit a rock a few years back! (Probably at the expence of the bar itself)
Really nice Carl, you have lots of brilliant ideas!
Really nice Carl, you have lots of brilliant ideas!
#21
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I saw this for the first time back in the 90's,
http://www.miatamania.com/Browse/Pla...omponentID=103
check out the inner fender brace too!!
http://www.miatamania.com/Browse/Pla...omponentID=103
check out the inner fender brace too!!
#23
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Did you test this with a belly pan?
That is to say, on the engine side of the pan.
You will need to just notch the sides of the belly pan in two spots slightly to gain the clearance for the Lower Frame Brace.
If you look at your pan now, it has a 1/2" raised lip on each side. This lip has several cut-outs in it now to clear the swaybar mounts and such.
This is the same way, you will need to cut or grind a small notch in the edge lip to clear the new frame brace. Then the belly pan goes right back up.
I can't find the price
For pricing and ordering information please click on this link:
http://www.928motorsports.com/parts/...rame_brace.php
I think you will be pleased at the price of the kit. There is also even more info about it there than I posted here, if you are hungry for more details.
#24
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FIRST to buy!!!
http://cgi.ebay.com/ebaymotors/ws/eB...m=350031487673
This should help me on tire wear!
http://cgi.ebay.com/ebaymotors/ws/eB...m=350031487673
This should help me on tire wear!
#25
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I think the question really becomes, how much camber is really changing in race conditions in the turns.
as many of you know, Anderson changed his settings from 2.5 degrees to under 2 degrees and found the car handled better and also stopped tearing up his inside edge. Ive advocated only 1.7 degrees in front for years. I still burn up the inside edge first, so it doesnt appear that the camber is changing that much in the turns. (toe was 1/16" out)
I do understand the concept, but i think I would like to see some hard facts on the theory that the camber is actually changing 1.5 degrees during turns. if the pivot point is the lower control arm near the chassis rails, whats the distance it has to move (twist)to create this kind of camber change? the bottom of the wheel would have to move in about .5" for this to occur as the bottom of the wheel is effectively pushing on the chassis rails. It also means that the compression of the upper components being pulled is nothing. Im sure there are some flex up there as well. I have a hard time believing that the wheels are moving that much. I can easily check this with a camera and some video over some hard turns. (and a visual meter and pointer)
mk
as many of you know, Anderson changed his settings from 2.5 degrees to under 2 degrees and found the car handled better and also stopped tearing up his inside edge. Ive advocated only 1.7 degrees in front for years. I still burn up the inside edge first, so it doesnt appear that the camber is changing that much in the turns. (toe was 1/16" out)
I do understand the concept, but i think I would like to see some hard facts on the theory that the camber is actually changing 1.5 degrees during turns. if the pivot point is the lower control arm near the chassis rails, whats the distance it has to move (twist)to create this kind of camber change? the bottom of the wheel would have to move in about .5" for this to occur as the bottom of the wheel is effectively pushing on the chassis rails. It also means that the compression of the upper components being pulled is nothing. Im sure there are some flex up there as well. I have a hard time believing that the wheels are moving that much. I can easily check this with a camera and some video over some hard turns. (and a visual meter and pointer)
mk
#26
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Mark -
I try to separate roll caged cars from non-roll caged cars in my description. A full 8-point roll cage (even more on the White Zombie) has handled this problem with the stiffness of the cage. As a result, 1.5 to 2 degrees of camber is the sweet number.
I don't assume most other 928's racing or doing track days or DE days have front roll cage members. In fact, I assume most of them do not.
I try to separate roll caged cars from non-roll caged cars in my description. A full 8-point roll cage (even more on the White Zombie) has handled this problem with the stiffness of the cage. As a result, 1.5 to 2 degrees of camber is the sweet number.
I don't assume most other 928's racing or doing track days or DE days have front roll cage members. In fact, I assume most of them do not.
#27
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If you would like to download and review the installation instructions, I have posted them here:
http://www.928motorsports.com/install.html
http://www.928motorsports.com/install.html
#28
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I think its great. Anything to stiffen the structure without having to do a full cage is a good idea.
#29
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I think this is a neat idea. It certainly won't hurt anything. I agree if you could make it into an X it would be stronger but as-is you are distributing the load between the two mounts. So any flex or rotation will now be shared between the two points.
However, how much flex/roll actually occurs and needs to be controlled is another topic. If this makes you feel better, then buy it or make it yourself.
However, how much flex/roll actually occurs and needs to be controlled is another topic. If this makes you feel better, then buy it or make it yourself.
#30
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I like it!
Consider it an anti-roll bar for the outside frame rail, in the longitudinal axis. In this application, you are sharing the torsional stiffness of the relatively-unloaded inside frame rail with the more heavily loaded outside rail. Plus it's relatively easy to remove for access if needed.
Carl, did you give thought to using just a straight section of box tube with holes and spacers for the bolt, no adjustability? Just curious.
Consider it an anti-roll bar for the outside frame rail, in the longitudinal axis. In this application, you are sharing the torsional stiffness of the relatively-unloaded inside frame rail with the more heavily loaded outside rail. Plus it's relatively easy to remove for access if needed.
Carl, did you give thought to using just a straight section of box tube with holes and spacers for the bolt, no adjustability? Just curious.
But the unloaded inside frame rail is still subject to steering geometry changes isn't it? I'm wondering if instead of engineering it in a manner that it transfers the load from one side to the other, if it would have made a difference to transfer the load to another point on the chassis that wouldn't affect steering geometry under load.
I'm asking because I DON'T know if it makes a difference. If it doesn't make a difference, then Carl's placement of the bar is by far the easiest access.