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Old 10-07-2009, 02:20 PM   #7936
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In my quest to end the terrible torque steer I am seeing, I rebuild the diff. I was going to replace the diff plates with some more of the light weight ones from BMI. I put them on a nice flat setup board and could see clearly the plate was not at all flat, more like pringle shaped slightly. I tried to sand it and it looked like it sanded flat (whole surface was sanded), but it was just because of the pressure used to sand it, that it temporarily flattened it while sanding.

I also noticed something else. Those lightened rings only "grip" the D hub in 2 very small points, (the edges of the "D") and over time the ring has worn away one edge of the "D" and let the diff ring move a bit back and forth.

after seeing this and the fact the rings were warped slightly, I went back to a set of trusty IRS rings I had from a while ago, sanded them up, they were true and flat, and because they have the full D profile they dont wear down those edges of the D hub and dont move at all.

Total weight difference is 1gm of rotational weight. The lightened rings come in at 2gm, the full normal ones at 3gm.

But alas... this did nothing to correct the torque steer issue. Starting to wonder if the flex plates are tweaked some how. The center pod doesnt perfectly center itself. (always sits to one side or the other a little bit.
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Old 10-07-2009, 03:18 PM   #7937
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Originally Posted by Clegg View Post
In my quest to end the terrible torque steer I am seeing, I rebuild the diff. I was going to replace the diff plates with some more of the light weight ones from BMI. I put them on a nice flat setup board and could see clearly the plate was not at all flat, more like pringle shaped slightly. I tried to sand it and it looked like it sanded flat (whole surface was sanded), but it was just because of the pressure used to sand it, that it temporarily flattened it while sanding.

I also noticed something else. Those lightened rings only "grip" the D hub in 2 very small points, (the edges of the "D") and over time the ring has worn away one edge of the "D" and let the diff ring move a bit back and forth.

after seeing this and the fact the rings were warped slightly, I went back to a set of trusty IRS rings I had from a while ago, sanded them up, they were true and flat, and because they have the full D profile they dont wear down those edges of the D hub and dont move at all.

Total weight difference is 1gm of rotational weight. The lightened rings come in at 2gm, the full normal ones at 3gm.

But alas... this did nothing to correct the torque steer issue. Starting to wonder if the flex plates are tweaked some how. The center pod doesnt perfectly center itself. (always sits to one side or the other a little bit.
Have you checked to see if the axle is centered properly? That is usually what does it. We have a hole drilled in the lower pod plate for you to measure from. The difference from the outside of the wheel to the hole in the lower pod should be no greater than .010 from left to right side.
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Old 10-07-2009, 03:19 PM   #7938
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does this apply for GT10 also??
Yup
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Old 10-07-2009, 03:20 PM   #7939
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Clegg,

If you cant get it figured out feel free to send your car to us and i will go through it for you
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Old 10-07-2009, 03:43 PM   #7940
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Thanks Jason! If I cant sort this out I'll deffinitely look at this option.
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Old 10-07-2009, 04:31 PM   #7941
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If you suspect the hockey sticks a simple way to check this is to swap them left and right and see if it pulls the other direction. I also took a cue from Jason Shreffler (sp?) and swapped the stand-offs where the hockey sticks connect putting the threaded one on the bottom. This allows me to have the chassis sitting on a flat setup board as I tighten down the screws on the hockey sticks to ensure it stays absolutely flat.
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Old 10-07-2009, 04:36 PM   #7942
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Starting to wonder if the flex plates are tweaked some how. The center pod doesnt perfectly center itself. (always sits to one side or the other a little bit.
I noticed that as well, that it doesn't always get back to 0 point, that's why I switched back to short mounting point on my DB12. DB10 seems to work fine also with the long flexplates. I am not sure if that's what causing your problem though..
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Old 10-07-2009, 08:55 PM   #7943
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I re-did the center shock completely, now with 60wt oil and the red spring. I did the best I could to check the rear track width side to side, its quite hard to use that center hole to measure the outter edge of each rim. I did the best I could and I think I found that one wheel was about .3 -.5 mm closer to the chassis than the other.

I trued down the fronts to pretty small since the R5 front lets me run them down to the plastic almost, no sense in carrying around more foam than needed and at least chunks wont disturb the car as much.

I also ordered some Magenta's for all around, and some pink rears to try out.

I did still notice the rear pod sat a bit to one side (I verified that the wires were not putting load on the pod), so what I did was put a small shim under the opposite flex plate at the point where the pivot ball connects to the rear pod, adn that seemed to make it sit even. I am going to test a bit to see if that helps or hurts.
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Old 10-07-2009, 11:54 PM   #7944
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Clegg, you have got the L plates freely moving on their pivots, and you have got the 10-32 screw in to make that adjustment? Sorry to call your building talents into question, but we had this problem here, and that's what it turned out to be. Once we got the screws in and adjusted, it went away.

My other suggestion (which just says your driving is bad!! Sorry again!!) is that the pod is twisted. I have had the two pod plates twist, and be held in that position by the cross brace. Release one of the screws in the cross brace, re-tighten, and the problem goes.

Hope that helps, if you're not mad at me!!
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Old 10-08-2009, 03:03 AM   #7945
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I hadn't thought of that...The F103 pods used to do that quite often as well...I'll have to double check that on mine
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Old 10-08-2009, 03:08 AM   #7946
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Originally Posted by SlowerOne View Post
Clegg, you have got the L plates freely moving on their pivots, and you have got the 10-32 screw in to make that adjustment? Sorry to call your building talents into question, but we had this problem here, and that's what it turned out to be. Once we got the screws in and adjusted, it went away.

My other suggestion (which just says your driving is bad!! Sorry again!!) is that the pod is twisted. I have had the two pod plates twist, and be held in that position by the cross brace. Release one of the screws in the cross brace, re-tighten, and the problem goes.

Hope that helps, if you're not mad at me!!
Also had same problem with the 10-32 screws being too tight causing the car not to center. After adjusting it was fine, but again after a few runs started up again... They did not get tighter, but some dirt got stuck inside, so they need to be cleaned from dust and dirt....
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Old 10-08-2009, 07:05 AM   #7947
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Originally Posted by SlowerOne View Post
Clegg, you have got the L plates freely moving on their pivots, and you have got the 10-32 screw in to make that adjustment? Sorry to call your building talents into question, but we had this problem here, and that's what it turned out to be. Once we got the screws in and adjusted, it went away.

My other suggestion (which just says your driving is bad!! Sorry again!!) is that the pod is twisted. I have had the two pod plates twist, and be held in that position by the cross brace. Release one of the screws in the cross brace, re-tighten, and the problem goes.

Hope that helps, if you're not mad at me!!
hehe No worries.

I rebuilt the rear L plate pivots, and yes the 10-32 screw is in just enough to remove any play in the balls but not binding.

I will check the twist factor on the plate though, I didnt check that.
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Old 10-08-2009, 08:39 AM   #7948
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Originally Posted by InspGadgt View Post
If you suspect the hockey sticks a simple way to check this is to swap them left and right and see if it pulls the other direction. I also took a cue from Jason Shreffler (sp?) and swapped the stand-offs where the hockey sticks connect putting the threaded one on the bottom. This allows me to have the chassis sitting on a flat setup board as I tighten down the screws on the hockey sticks to ensure it stays absolutely flat.
You do understand that that will alter the handing of the car because it lifts the front of the flex plate above level, so the rear axle will tend to steer out from the corner in roll instead of into the corner if built as kit.

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Old 10-08-2009, 12:17 PM   #7949
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Yes I do...but I've had suggestions in the past to put a shim under the front of the hockey stick which does the same thing...and that's how Shreffler and Fairtrace had their cars setup at the Snowbirds...if it's good enough for them...it's good enough for me
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Old 10-08-2009, 04:39 PM   #7950
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Yes I do...but I've had suggestions in the past to put a shim under the front of the hockey stick which does the same thing...and that's how Shreffler and Fairtrace had their cars setup at the Snowbirds...if it's good enough for them...it's good enough for me
Jason,

I am new to your car (Lipo Edition) and would like some setup sheets from some top level drivers like Schreffler and Fairtrace. They are not currently posted on your site, where can we find them?

The car is very good! Very pleased so far (2 club race days worth of tuning). I solved a slight torque steer problem by shimming the axle as you suggested. I am using the CRC FE on the car, which works quite well. With a new car, I would like to learn a range of adjustments so I'm prepared to match track conditions. As mentioned above, what would be the "condition" that would require placing a washer under the front mount of the hockey sticks and what is the handling characteristic it will produce?

Each of us has a slightly different feel and driving style to match our car with and having some of your insights and driver setups would be great!

Thanks,

Aaron
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