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Old 09-30-2009, 05:33 AM   #7921
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That is correct. Ditch the black fronts as they make the car push pretty bad. I would also go to the angled servo. That will help alot with turn in. Try #4 on the tubes and king pins as that will help also.
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Old 09-30-2009, 07:14 AM   #7922
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That is correct. Ditch the black fronts as they make the car push pretty bad. I would also go to the angled servo. That will help alot with turn in. Try #4 on the tubes and king pins as that will help also.
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Originally Posted by InspGadgt View Post
Running a flat servo your going to get some bump steer, the medium ball studs help reduce it but don't completely eliminate it. Most ppl run 1/3rd to half sauce on the front so it could be the blacks are not aggressive enough since you are having to sauce the full tire. Might want to try dbl. pink. That's what I ran on carpet at the IIC.
i had forgotten that the turn-in was better with the angled servo, i will go back to that.

regarding lube choice: i went to #3 in the tubes because it would diff with #4, is there a front end change that can compensate?

tire choice: i had been wanting to run a softer tire, but this carpet is less than a year old and in the first or second month of running we were getting a glazing on the untreated portion of the fronts, only the blacks were drivable in the first half of the race.
it had been suggested that the glazing in the front was due to too much rear grip and increased front slip angles. i was practicing last weekend with lilac/grey and short flex bars, and was only getting very little glazing.
however it felt a little slippery in the fast sections and still a little push in the tighter sections.

in the meantime, i will switch back to an angled servo and try again.

Last edited by avs; 09-30-2009 at 07:24 AM.
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Old 09-30-2009, 07:32 AM   #7923
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Originally Posted by avs View Post
i had forgotten that the turn-in was better with the angled servo, i will go back to that.

regarding lube choice: i went to #3 in the tubes because it would diff with #4, is there a front end change that can compensate?

tire choice: i had been wanting to run a softer tire, but this carpet is less than a year old and in the first or second month of running we were getting a glazing on the untreated portion of the fronts, only the blacks were drivable in the first half of the race.
it had been suggested that the glazing in the front was due to too much rear grip and increased front slip angles. i was practicing last weekend with lilac/grey and short flex bars, and was only getting very little glazing.
however it felt a little slippery in the fast sections and still a little push in the tighter sections.

in the meantime, i will switch back to an angled servo and try again.
We have the new crc carpet at our track also. Black front and yellow or pink rear are the only tires that will hold on for the whole 8mins. Tried dbl pink front and rear in mod and it was great. Held on the whole run. Tried magenta all around in stock and it was pretty good but the whole car got skatty after 7 mins. Wish I could find pink all around. Bet that would be the ticket.

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Old 09-30-2009, 10:27 AM   #7924
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If the carpet is still fuzzing up the only tire that will keep will be the blacks. When i run with jack the gripper, the fronts gum up if you run anything other than purple or black. The purples gave the car more steering and didnt gum up. I ran them with yellow rears and that worked great. Try the long flex plate mount and install the set screw but dont touch them to the chassi. This should help alot.
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Old 10-06-2009, 06:43 PM   #7925
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Wow this is one dead thread.


Anyway... now I know my BMI isnt exactly stock, but it is close enough that setups should transter more or less.

The issue I am having now is some terrible torque steer/breaking, and still getting issues with the car flipping if I transition in a corner hard.

The basic setup is:

F:
.22
~5deg blocks (R5 front end which is set more or less at the same config as my L4 was).
Flat Servo
3.5mm height
-1 - -1.5 camber
Black Fronts

R:
Silver spring, 50wt oil in silvia shock, with teh forward mount at = to the tall setting with some washers under it.
Standard flex plates, in long position
Tubes with Sure Lube 3 on em
Yellow Rears
3.5 - 4mm ride height
1mm droop

The biggest issue is when I hit the breaks with this 10.5T 1S setup, the car will dart to the "drivers side", and when I punch the throtle, it darts the same way.

Rebuilt the dif, new flat plates, new bearings all around, and it spins free.

The other big issue is when at the end of a straight if I try to pivot the car around a corner the car will go up on 2 wheels and roll onto the antenna. And that nicely chunks up the tires. If I run Grays I dont have the issue as much, but I also have almost no forward bite.

Its getting quite frustrating that I cant null out this car and just get it to drive consistnetly lately... the track layout is terrible at the track currently, its super high speed, and super technical, best I can describe it is a series of drag strips wit hair pin turns at the end... and this car is just not handling it well.

A friend also has a 12RR, and has the same flipping issue around corners, hes also getting quite frustrated and nothing he has changed has nulled out the tendancy for this chassis to do that. Hes swapped flex plates, set them differently, changed tire compounds, etc...
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Old 10-06-2009, 07:26 PM   #7926
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What height are you truing the tires to? Are you CA'ing the sidewalls?
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Old 10-06-2009, 07:31 PM   #7927
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I had the same layout a month ago at our local track with the same problems. I went to a magenta tire and it seemed to help out. I think I also raised the ride height in the rear. This might help.
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Old 10-07-2009, 06:09 AM   #7928
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The silver spring is too soft. That will make the rear of the car too planted. Try going to the gold or red. Torque steer can occur from the axle not being shimmed correctly for center, gritty diff, or the car isnt balanced properly. Check all of those and you should be good. Also make sure the pod is level at ride height.
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Old 10-07-2009, 06:11 AM   #7929
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as for traction rolls, make sure you have your shock in the short position. The longer your center shock is, the more of a chance you will have for traction rolls. Also try starting your tires at 1.750 rear and 1.650 front. Reduce your camber to 1 degree and see how it goes.
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Old 10-07-2009, 06:33 AM   #7930
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Ahh I thought the shock should go higher to reduce traction roll... I was moving it the wrong way! hehe
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Old 10-07-2009, 06:53 AM   #7931
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Quote:
Originally Posted by protc3 View Post
as for traction rolls, make sure you have your shock in the short position. The longer your center shock is, the more of a chance you will have for traction rolls. Also try starting your tires at 1.750 rear and 1.650 front. Reduce your camber to 1 degree and see how it goes.
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Ahh I thought the shock should go higher to reduce traction roll... I was moving it the wrong way! hehe
Hey Jason,
when you say 'short position', do you mean moving the front support farther aft? (which also makes the angle of the shock a little steeper)

but raising the front support also shortens the shock(while making the angle less steep)

the question in my mind is if the key parameter is shock angle or shock length? in an earlier post you suggested a 2.95" shock length, which puts the front position one step fwd from the shortest position. so am i understanding you correctly that the suggested change to reduce traction rolls is to move the support aft, and shorten the shock as needed to maintain droop?
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Old 10-07-2009, 10:34 AM   #7932
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I would also recommend trying a standard AE .020 front spring. The linear springs are great, and I used the .022 almost all of last year, however on layouts with lots of hairpins/180's, the linear springs just don't feel good to me. The benefit from them is usually amazing on flowing tracks where the spring stays loaded throughout the entire turn. With a layout that is straight->hairpin, the linear spring can collapse when tossed hard into a turn under braking.
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Old 10-07-2009, 11:35 AM   #7933
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The shock length im speaking of is the actual antenna mount location on the chassis. The shorter it is, the less traction roll issues you will have. I normally run it in the 2nd to last position from the rear. If it is traction rolling i will move the mount all the way back. For shock angle i adjust for the conditions. I start a stiff spring high and lower it as i need to.
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Old 10-07-2009, 12:37 PM   #7934
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Quote:
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as for traction rolls, make sure you have your shock in the short position. The longer your center shock is, the more of a chance you will have for traction rolls.
does this apply for GT10 also??
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Old 10-07-2009, 12:51 PM   #7935
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Quote:
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The shock length im speaking of is the actual antenna mount location on the chassis. The shorter it is, the less traction roll issues you will have. I normally run it in the 2nd to last position from the rear. If it is traction rolling i will move the mount all the way back. For shock angle i adjust for the conditions. I start a stiff spring high and lower it as i need to.
ahh, ok thanks. that helps. (i always appreciate the 'strategy' guidance)
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