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Suspension Limiter

jcarius

Well-Known Member
#1
Howdy Folks,

On the front of our nine car, the previous owner set up limiting straps that don't work all that well.
Looking around, it seems the majority of folks are using the hook style front end limiters. These always
seem to me like they must be hard on the arms ... any other suggestions?

Thanks!

Jim and Vanessa
 

Protech975

Well-Known Member
#2
J & V
The limiting straps just won't cut it on a 9 car if you plan on running hard so scap that idea!
As for the Hook and pin set up, because of where the hooks are welded to the arms thay do not overlly stress the arms. The lower hook is the one that take most of the beating so as long as you keep your set up and measurments straight you should have no problem. The only problem I had was that the pin may have a tendancy to bend back and kink the tower so support it as much as possible. also the pin will get knifed by the lower hook so to solve this I put a small piece of curved 1/4 plate {1" sq.} that matched the curve of the pin right at the spot the hook contacted the pin and welded it to the hook,this will greatly increased the contact area. Works great never again did I have to weld up notched pins. I called them strike plates.
Also make sure you run the rubber bumpers stops on your shock shafts so that if there is a change in the geometry of your stops during a race you will not be bottoming out your shocks. Rob S. #975
 

TimHayosh

Well-Known Member
#3
I don't think I have any pictures of it, but I used a hook on the top AND the bottom arm. This way the net force on the pin was zero. Never bent a pin. Plus, the load is shared by both arms reducing stress to the arms. Worked for me.
 

Protech975

Well-Known Member
#4
Tim
I used hooks on both arms as well, are you refering to a hook on the back side of the upper arm so that both hooks contact the pin at the same time? There are several different ways to set up hook stops. but over all they are the best setup to race with. R.S.
 

TimHayosh

Well-Known Member
#5
I'm thinking now that I do have a picture of this. If I get the chance tonight, I'll post it.
I've also seen some really cool setups using a flat piece rather that a hook.
 

jcarius

Well-Known Member
#6
Gentleman,

thanks a bunch for the input - you've confirmed my conclusions ...
Tim, if you can post that pic I would be grateful - any other info about the flat stock solution would also be appreciated.

Thanks Again,

Jim & Vanessa


(PS - We're looking for another nine car - if anyone hears about a reasonably priced/equipped singel seater - please let me know!)
 

TimHayosh

Well-Known Member
#7
I'll see if it's been downloaded from the camera...might already be on the hard drive at home...stay tuned.
 

TimHayosh

Well-Known Member
#8
It took a while, but I finally found the pix.

In the first one, the suspension is a ride height. Yes, I had 0.00" of droop! As you can see, you must cycle the arms to ensure they won't hit. I used this set up on about 4 sets of arms. Only once did I have to trim the hooks so they won't hit each other. NOTE: In these pictures, the hooks are only tack welded.






In this pic, the suspension is at full compression. Notice the upper and lower hooks engage the pin at the same time. Each arm now shares the load, and the pin is not being "asked" to bend. There are additional benefits: If you have only one arm stopping your compression load, you are effectively asking that ball joint to leave it's housing. This was explained to me by long time Class 9 racer known here as "sadrace".



Here to help, Tim
<P ID="edit"><FONT SIZE=-1>Edited by TimHayosh on 02/08/02 11:31 AM (server time).</FONT></P>
 

mike_hinson

Well-Known Member
#9
Tim,
Excellent pics. Really provides the info we need. I can see where this setup would spread the load to both arms and help extend the life of the beam and ball joints. I'm going to try this myself.
Thanks,
Mike Hinson
 

AllwaysRcn

Well-Known Member
#10
Tim
With both hooks on the upper arms, did you notice it being "easier" on the Ball joints? Or did you still replace them every race just to be safe?just curious-I have allways just replaced them every race...
 

TimHayosh

Well-Known Member
#11
Trey, I still always replaced them. They are only $10-12/ea from Joel Mohr or Kartek. So, what's the point of reusing them? In the 2 years I drove this car, I never had a ball joint failure. I believe if you cycle your suspension properly when installing the hooks, the ball joints won't be stressed beyond their design limits. "Sadrace" also told me that if I wasn't hitting the stops constantly, I was driving too slow. So, that's what I did. I was on the hooks all the time. The ball joints never failed. THIS IS NOT A GUARANTEE! It's just my own experience.

Happy motoring, Tim

<P ID="edit"><FONT SIZE=-1>Edited by TimHayosh on 02/09/02 07:36 AM (server time).</FONT></P>
 

jcarius

Well-Known Member
#12
Tim,

Thanks so much for taking the time to post the pictures. I placed (yet another) order with McKenzie's,
and I'll be working this out this weekend.

Take care,

Jim
 

Protech975

Well-Known Member
#13
Hey Guys
Here are some pictures of the strike plates I mentioned earlier, They are cut out of a piece of curved 1/4 in. plate and match the curve of the stop pin.
I would guess that they are about 3/4 X 1 in square and greatly increase the contact area on the pin and will stop the knifing action of the hooks.
You will also notice the odd angle of the Balljoint stem! I took this arm off my car after we won a 250 mile race last year in which I flipped the car 3/4 of a mile off the start line, I landed on all fours and kept going depite a bent up front-end and a bent rear axle. after taking this arm off I noticed that the balljoint was bent at a 20 degree angle and cracked but it still held for 249 more hard racing miles! Goes to show you how tough these German "Lemforder" joints are. Rob S. #975
 

Attachments

TimHayosh

Well-Known Member
#15
Great pictures Rob!
I posted some similar ones, with similar praise for Lemforder after a 5-1600 decided to use the right side of my car for a landing strip. I really like the little piece welded into the hook! (Although I never experienced the "knifing action", I would do it anyway; it looks so cool!)

Happy motoring, Tim
 

Cameron

Well-Known Member
#16
I have done the same thing on the front of our nine car arms, but just used a piece of 1" tubing and
have had no problems with the thinner material. And you are right on how much the hook
will cut in to the rod.

<font color=red>Cameron</font color=red>
<font color=yellow>BRAT Racing # 936</font color=yellow>
 
#18
The best I have seen is what the Big Worm(doug969) is doing. I ran the hook and pin but the set up that doug runs seems to be better(more contact area)and alot more simplier.The Main selling point to this system is you don't need to match set arms and beams they are fitted off a jig.Which means you can order them over the phone with out re-cycling your beam/arms everytime. Of course once the stop has been set on your beam.
 
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