Losi XXX-S

Old 10-31-2003, 09:57 AM
  #7591  
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KEVIN K:

did the overall feel of the car change, like more inital steering, a tendency to oversteer... etc.

would this mod require additional tuning to the car?
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Old 10-31-2003, 10:07 AM
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Racer....when you run this mod you have to cut the droop screw holders off of your front bumper.....it move the inner hinge pin into it. Yeah the over all feel of the car changed but maninly on steering exit. Now I have only run this on foam tires if your running rubber tires Im not sure how this will work but give it a try and let me know.
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Old 10-31-2003, 12:25 PM
  #7593  
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Default roll centers

Ok i'm a little confused??? which is the high and low? is it the short one the low roll center and tall ones the high roll center??
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Old 10-31-2003, 12:29 PM
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Can somebody post the height of the front Losi molded low roll center mounts so I can grind down a set of freshies...?


Thanks.
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Old 10-31-2003, 01:09 PM
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yep
tricklosi- the shorter roll centers are the low ones, the descriptions match the name alittle.
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Old 10-31-2003, 01:12 PM
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Cool thanks....i know it was a little stupid but there's no doubt now, thanks...
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Old 10-31-2003, 01:28 PM
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Ok when I drove the car with the 2r block in the front it gave the car more steering and it just felt better on corner exit. Now what this mod does is two things one is it narrows the front track a bunch and changes the drive shaft angle. Your wheel base is also slightly changed as well. I was told once by a very well respected person in RC that the drive shaft angle controls on power traction at that end of the car. Example....if the front CVDs are angled towards the back of the car they will have less on power traction and if they are angled towards the front they will have more on power or forward traction. I dont know I cant speak for why Losi did that but I would think it had something to do with making the car easy to drive for everybody or something like that.
Kevin K thanks, I agree with you regarding the way drive shafts angle affects car handling. But don' t you think (with the adoption of 2R in front) is the change of the angle of the arm pin (view from top) the main reason for better steering when exiting the corner? The way I did the job didn' t change front track and only a little bit in wheelbase. I think when the car rolls the angle of the pin causes abrupt changes somewhere, toe in/out, caster, etc.
If pins are parallel car seems more neutral. Other cars have no angle...
Thanks again,
EddiRossi.
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Old 10-31-2003, 03:13 PM
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Eddi....I think that the biggest effect from going to the 2R block is the change in front width more then anything. But I have no way to prove any of this the only way would be to try a slightly shorter front arm with a 2F block in the front. And There is too many other factors that come into play when a car rolls like camber location, castor, rideheight and so on its hard to say that the Pin angle causes any abrupt changes......that would require a test team and I dont think that what I did or have done is something that the factory has not tried once before. I dont know if I answered your question or not.

Ok on some cars you dont see the pin angle per say but you do see the drive shaft angle and I think that is close to the same thing as pin angle. Pin angle might also have something to do with the way the suspension "packs" up or down in its movement?????
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Old 10-31-2003, 04:42 PM
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Kevin K, yes of course you answered my question, thanks!
You are right when say too many things change when the car rolls...on my local track, a very fast one, were we race foam tyres on asphalt, in the last race I had my car very twitchy through the corners. To reduce car roll I brought the droop (not on the gauge, the effective droop I mean) down to something around zero: car was awesome!
Anyway I' ll keep on testing and playing with different tech solutions on the XXX-S G+ : it' s so enjoyful!
EddiRossi.
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Old 10-31-2003, 04:46 PM
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Cool man post what you come up with in testing.
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Old 10-31-2003, 06:53 PM
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Originally posted by jkerr0043
Why not just hang onto the Losi just in case? Need to recoop some $$$?
Yea, just usin the cash to buy the new car, I didn't lose much on the Losi at all, so it's not all that bad.

The Yok SD I'm going to be building will be one of a kind All I have to say is red and gold should look good together
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Old 11-01-2003, 06:48 AM
  #7602  
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Originally posted by Kevin K
Racer....when you run this mod you have to cut the droop screw holders off of your front bumper.....it move the inner hinge pin into it. Yeah the over all feel of the car changed but maninly on steering exit. Now I have only run this on foam tires if your running rubber tires Im not sure how this will work but give it a try and let me know.

Kevin, thanks, will try it out next week... have an upcoming big race and i dont want to upset my setup for the moment, but thanks for sharing this mod, i defintely would like more exit steering on the losi.
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Old 11-01-2003, 06:50 AM
  #7603  
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Originally posted by EddiRossi
To reduce car roll I brought the droop (not on the gauge, the effective droop I mean) down to something around zero: car was awesome!

EddiRossi.

what do you mean by effective droop?
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Old 11-01-2003, 08:18 AM
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Originally posted by Randman
Yea, just usin the cash to buy the new car, I didn't lose much on the Losi at all, so it's not all that bad.

The Yok SD I'm going to be building will be one of a kind All I have to say is red and gold should look good together
GSG Interesting.
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Old 11-01-2003, 08:54 AM
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Originally posted by jkerr0043
GSG Interesting.
GSG is new to me
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