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Pros/Cons of Locking Out Kinematic Toe

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Old 03-05-2011, 08:56 PM
  #61  
jdistefa
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Originally Posted by sonny1
I see that you guys are increasing front track by using wider rubber which it is ok, another way for increasing the track is by changing the front suspension pick-up points outward,there is provisions for it on the chassis itself.,(a la RSR's)cheers.
Yup, 30mm increased track each side
Old 03-06-2011, 01:12 AM
  #62  
MarkD
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Epic thread...

so much detail
great place
Old 03-06-2011, 09:19 AM
  #63  
bobt993
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Originally Posted by jdistefa
Yup, 30mm increased track each side
Yes, but if you plan to race this car you have a laundry list of parts needed:

EVO uprights, GT2 tie rods, alteration of the lower carriers (some are factory drilled on the earlier cars). Movement of the brake booster if so equiped. Movement of the solid brake lines. Movement of the brake pedal arm. Alteration of the front sway bar drop links. ERP camber plates for max range. I had to run mine in reverse to down to 3.5 deg of camber. Fenders flares to maintain proper offset and scrub radius......... End result is top notch handling and 10inch rims up front. Ironically you can still run small tires on existing rims with improved traction.
Old 03-06-2011, 09:44 AM
  #64  
Gasser
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Bob993,

Bout got mine track ready finally. Just finishing up rebuilding the brakes and Im off to TWS for my first race weekend and testing. Gonna be interesting for sure. Not sure how much learning curve Im gonna have in this new beast.

Jeff
Old 03-06-2011, 09:58 AM
  #65  
bobt993
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Jeff, start with the front sway middle to middle loose and middle on the rear bar. As you get better with the abrupt turn in, move the front sway to full loose. Experiment with this and look at data to decide on a per track basis. Chris prefers slight understeer at tracks like WG, but Summit Point and Tbolt you want an oversteering monster for the slow speeds. Keep me posted I am sure you gonna love the feel. BTW what camber did you end up with fr and Rr? What front end is on your car now?
Old 03-07-2011, 12:49 AM
  #66  
Gasser
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I put the EVO 2 front end on and it fits perfect. I spaced my front wheels out 5mm but could have gone a few more. The rear wheels I spaced out 17mm with a hub centric spacer to get as wide of a track as I could. My flairs gave me a lot of room out back. I put the 17 spacer on the front and they fit but would probably have torn up my front flairs. Ill probably settle on 10 to 13 in the end to get the best track. Chris wanted it as wide as I could get it.

Ill check the exact numbers Chris got me but its roughly neg 4 in front and in the neg 3s in the rear. If you PM me your e mail Ill shoot you the allignment sheet he gave me. He set up my suspension for the Yoko slicks. To the naked eye it looks crazy!

I think that is exactly where he has my sways set right now and Im about mid range on my shocks but told me I will probably like it at full stiff once I get use to every thing. I have a full DE day with lots of track time so I plan on making a lot of big changes just to see how all the different settings work and feel.

Ive got a LOT to learn this first weekend as there is sooooo much new from the suspension, tires, wheels , springs and most of all, all my shift points with the new full race tranny. First gear goes almost to 70 mph Basically its a new car.

Ill keep ya posted.

Jeff
Old 05-24-2011, 08:51 PM
  #67  
Paul902
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Originally Posted by vincer77
Thanks for the explanation and yes, this all seems to agree with Bill's post of the Porsche explanation of the suspension. S
Great thread...what still doesn't make sense to me is that according to the Porsche explanation, links 1,2,3,4 are rigidly mounted and link 5 is elastic, but we've seemed to suggest that 1 is rigidly mounted (the monoball Chris posted pics of) and 2, 3, 4 and 5 are ALL elastic (rubber bushes).
Old 05-24-2011, 09:21 PM
  #68  
Bill Verburg
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Originally Posted by Paul902
Great thread...what still doesn't make sense to me is that according to the Porsche explanation, links 1,2,3,4 are rigidly mounted and link 5 is elastic, but we've seemed to suggest that 1 is rigidly mounted (the monoball Chris posted pics of) and 2, 3, 4 and 5 are ALL elastic (rubber bushes).
you are confusing rubber w/ elastic. A rubber bush will have a limited amount of play in any direction, the elastic link #5 is much more so and in only one plane. The intent is to change the toe in a controlled manner to help in cornering. Fine for street use but mostly undesirable in a track car
Old 05-25-2011, 07:28 AM
  #69  
Paul902
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So, 2,3, and 4 are rubber and 5 is somehow different? What technology or design makes 5 elastic? When you got your RS arms, was 5 still different from 2,3, and 4?
Old 05-25-2011, 09:10 AM
  #70  
Bill Verburg
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Originally Posted by Paul902
So, 2,3, and 4 are rubber and 5 is somehow different? What technology or design makes 5 elastic? When you got your RS arms, was 5 still different from 2,3, and 4?
It's just a much softer rubber, you can easily move it by hand, not so w/ the other rubber bushes.

RS rubber bushes are even stiffer yet
Old 05-26-2011, 01:12 AM
  #71  
Greg H.
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What is the practical difference between installing monoballs and replacing the arms with ERP links?

Greg H.
Old 05-26-2011, 08:39 AM
  #72  
Bill Verburg
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Originally Posted by Greg H.
What is the practical difference between installing monoballs and replacing the arms with ERP links?

Greg H.
ERP links will give you more control over the geometry of the rear end. To my mind that is going way beyond what most of us are capable of dealing w/.

For a track only car the stock arms w/ all monoballs & solid sides is going to be more than satisfactory.

For a dual use car I'd use the Elephant racing hard rubber bushes except for the toe links which almost have to be monoball w/ locks & solid sides.

the big negative w/ monoballs is durability. I have had to replace them after as little as 1 yr and ~1400 track miles, pretty expensive.
Old 05-26-2011, 11:29 AM
  #73  
Greg H.
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Bill - Why does the toe link have to be monoball?

I've been thinking about installing the tilt kit, and after this thread, changing out the bushings while I'm at it. Even though my car is 30% track (The other 70% going to and from the track) I am leaning toward the RS style rubber bushings, just because I'm a bit leery of going too far. So the question is the Kinematic bushing: Monoball or RS hard rubber.

Greg H.


Edit: I noticed on all the ads for the aftermarket toe links, they say that there isn't enough adjustment with the factory toe link on a lowered car. My car is pretty low already - maybe I'm runnig too much toe or something else is compromised?

Last edited by Greg H.; 05-26-2011 at 11:59 AM.
Old 05-26-2011, 05:50 PM
  #74  
Paul902
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Originally Posted by Bill Verburg
It's just a much softer rubber, you can easily move it by hand, not so w/ the other rubber bushes.

RS rubber bushes are even stiffer yet
But in the RS kit, is 5 softer than 2,3,4? IE did Porsche leave the same kinematic effect in the RS? When you replace with aftermarket rubber bushings you get all the same for 2,3,4,5.
Old 05-26-2011, 06:40 PM
  #75  
vincer77
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Originally Posted by Bill Verburg
ERP links will give you more control over the geometry of the rear end. To my mind that is going way beyond what most of us are capable of dealing w/.

For a track only car the stock arms w/ all monoballs & solid sides is going to be more than satisfactory.

For a dual use car I'd use the Elephant racing hard rubber bushes except for the toe links which almost have to be monoball w/ locks & solid sides.

the big negative w/ monoballs is durability. I have had to replace them after as little as 1 yr and ~1400 track miles, pretty expensive.
Do monoballs experience short life in all applications? It seems to me (w/o modeling as you suggested earlier) that if all the mounts are solid, then there may be binding in the suspension leading to excessive loads on the *****.


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