Drop spindle discussion
#61
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Are they bending in a similar location and is it a simple matter of just adding a little gusseting. I also wonder if its a bad batch (material is wrong or out of spec) or its a design problem.
#62
It sounds like the several comments of "autocrossers bend stuff that road racers can't" are based solely on problems with early V8R arms. The spherical bearing tubular Cr-Mo type arms used on Jesse Prathers EP car would probably be just fine on a national level SSM or CSP car.
Soo..
Back to the context of the thread, yes any drop spindles designed for the Miata should be strong and stiff enough for any conceivable usage they might see, including autocross.
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#63
V8R has revised their tubular arms no less than 5 times that I know of.
It sounds like the several comments of "autocrossers bend stuff that road racers can't" are based solely on problems with early V8R arms. The spherical bearing tubular Cr-Mo type arms used on Jesse Prathers EP car would probably be just fine on a national level SSM or CSP car.
Soo..
Back to the context of the thread, yes any drop spindles designed for the Miata should be strong and stiff enough for any conceivable usage they might see, including autocross.
It sounds like the several comments of "autocrossers bend stuff that road racers can't" are based solely on problems with early V8R arms. The spherical bearing tubular Cr-Mo type arms used on Jesse Prathers EP car would probably be just fine on a national level SSM or CSP car.
Soo..
Back to the context of the thread, yes any drop spindles designed for the Miata should be strong and stiff enough for any conceivable usage they might see, including autocross.
It is interesting that EP Miata’s design for their rear upper arm has zero for aft stiffness only attaching to one of the chassis side spots. Must just twist the hell out of the lower arm with for/aft and braking loads.
The V8R arms look better but they did go through some design iterations that looked pretty sketchy to me on the front lowers.
Last edited by bbundy; 02-07-2013 at 12:05 AM.
#64
I know an SSM Miata that completely folded both sides at once a set of EP Miata front upper arms during straight line braking on a smooth asphalt surface during the first event on them. They claimed they had never had a failure before.
It is interesting that EP Miata’s design for their rear upper arm has zero for aft stiffness only attaching to one of the chassis side spots. Must just twist the hell out of the lower arm with for/aft and braking loads.
The V8R arms look better but they did go through some design iterations that looked pretty sketchy to me on the front lowers.
It is interesting that EP Miata’s design for their rear upper arm has zero for aft stiffness only attaching to one of the chassis side spots. Must just twist the hell out of the lower arm with for/aft and braking loads.
The V8R arms look better but they did go through some design iterations that looked pretty sketchy to me on the front lowers.
#65
We'll have to see what I end up concocting when I get around to having time to design a full set for my car. I fully intend to manufacture a jig for welding them so I could potentially bring these to market as I wont be limited by my agreement with the shop at school that doesnt allow me to make a profit. Mmm no compromise arms designed specifically for SSM or higher cars, with actual FEA backing them up. Hopefully I'll get around to this before I nuke a set of stock arms.
As long as you add some extra adjustability for camber.
#66
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Andrew Keisler(a guy from Knoxville,TN) is getting serious about a prototype drop spindle.
Drop Spindles 101
I told him to send a prototype to you, Emilio. I also asked him about the loss of droop travel. I'm going to guess some spacers would be a lot easier than having a whole new shock made, initially at least.
Edit: Not 100%, but last I heard he's shooting for a ~$800 or less price-point.
Drop Spindles 101
I told him to send a prototype to you, Emilio. I also asked him about the loss of droop travel. I'm going to guess some spacers would be a lot easier than having a whole new shock made, initially at least.
Edit: Not 100%, but last I heard he's shooting for a ~$800 or less price-point.
#67
Andrew Keisler(a guy from Knoxville,TN) is getting serious about a prototype drop spindle.
Drop Spindles 101
I told him to send a prototype to you, Emilio. I also asked him about the loss of droop travel. I'm going to guess some spacers would be a lot easier than having a whole new shock made, initially at least.
Edit: Not 100%, but last I heard he's shooting for a ~$800 or less price-point.
Drop Spindles 101
I told him to send a prototype to you, Emilio. I also asked him about the loss of droop travel. I'm going to guess some spacers would be a lot easier than having a whole new shock made, initially at least.
Edit: Not 100%, but last I heard he's shooting for a ~$800 or less price-point.
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#69
Weekend Racer has these up now, drop spindles with bolt on sealed front bearings...
Miata Front Chromoly 1.5 Drop Spindles with Race Hub - $799.00 : Weekend-Racer - Auto Racing Safety Equipment, Auto Racing Gear, Auto Racing Helmets, Auto Racing Suits, We're amateur racers just like you.
Miata Front Chromoly 1.5 Drop Spindles with Race Hub - $799.00 : Weekend-Racer - Auto Racing Safety Equipment, Auto Racing Gear, Auto Racing Helmets, Auto Racing Suits, We're amateur racers just like you.
#71
I just installed Keisler Automation's drop spindles up front.
What I have are prototypes - first set other than what Andrew has tested on his own car.
All aluminum. Super light. 2" drop. Priced better than you can imagine.
He's tweaking the design slightly right now and is also working on a design with a bolt on hub.
What I have are prototypes - first set other than what Andrew has tested on his own car.
All aluminum. Super light. 2" drop. Priced better than you can imagine.
He's tweaking the design slightly right now and is also working on a design with a bolt on hub.
#76
One trouble becomes tire temps. I would be seriously concerned with even an auto-x turbo miata overheating the 255 13 hoosiers in the A6 compound in the middle of a run. And the other trouble is the 275 is faster than the 255. I dont know what the road racer options are. But I know some of those guys are already running the super short 13" options.
#77
But as we all know, tires are not available on custom order (any size, any construction, any compound, any thread, ...) but rather as discrete options and you have to adjust to what's available.
I'd love to have 1" drop in the spindles and gain angles, bump range (with less than optimal dampers), etc.
If there are several designs on the way now, it will probably be something nice and decently priced to aim for in 2018 or so when I get around to it...
#78
Asking since the main use of such spindles would be Miata prepped for racing. And if the class allows ABS, a Miata with a decent ABS would be faster than non ABS one every time (assuming everything else on the two cars is the same of course) ...
#80
I recently installed the rear driftworks knuckles in my s13. I had to go from 16 to 17" rims to stop the LCA scrubbing the inside of the wheel under hard compression, had to change shocks to stop them from fouling on the drive shafts (I have larger skyline gtr diff and shafts). There was a few other small things like rearranging brake lines, but nothing major. These are obviously very specific to the car and the more extreme 40mm drop, but still some things to be aware of for these types of products.