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Old 01-27-2012, 12:04 PM   #1471
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As a question for Oleg, do you have any advice on how to adjust the bump steer spacers when adjusting castor on the front/rear? Or just play it as you see it?
...
Good first step for removing of bump steer is to keep the steering rods approximately parallel to corresponding upper arm (or something between the upper and lower arm) if you look at the car from behind or from front.

Please use setup station for fine adjusting of bump steer.
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Old 01-28-2012, 09:50 PM   #1472
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Good first step for removing of bump steer is to keep the steering rods approximately parallel to corresponding upper arm (or something between the upper and lower arm) if you look at the car from behind or from front.

Please use setup station for fine adjusting of bump steer.
Thanks Oleg, will bare the above in mind when adjusting.
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Old 01-28-2012, 10:37 PM   #1473
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Dear friends,

Suspension stiffness in the cars of Ronald Volker and Jilles Groskamp are as follows according to my calculations:

Front suspension 87-96 gF/ mm
Rear suspension 109-116 gF/ mm

All the latest published Ronald's and Jilles's set-ups are placed within these ranges of suspension stiffness.

Please note : this is not the stiffness of individual springs but the total suspension stiffness - same as on our graphs.

I think that it is good start point to find your right springs setup for A700.
I've noticed many setups with less gF/mm in the front vs. the rear. I find this odd compared to many setups I've run on other TCs. Am I misunderstanding that a lower gF/mm is a softer suspension?
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Old 01-28-2012, 10:53 PM   #1474
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Default Fantastic Customer Service

Recently received an order minus the GD Case 2 which I ordered.

Oleg himself has shipped it to me along with some other items I have subsequently ordered. No shipping was charged for the additional items.

Great product and fantastic support. What more could you ask for?

Thanks Oleg, very happy customer

Cheers Alan
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Old 01-28-2012, 11:05 PM   #1475
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I've noticed many setups with less gF/mm in the front vs. the rear. I find this odd compared to many setups I've run on other TCs. Am I misunderstanding that a lower gF/mm is a softer suspension?
Most "Conventional" TC's have the rear shocks lower pickup point further out ( compared to the fronts ( because the fronts need clearance for the tire to turn and not hit the shock )). So the rear shock/springs have more leverage compared to the fronts because they pickup further out ( on the lower A-Arm ). So softer springs are used in the rear to compensate for the difference in leverage. The end effect is the rear is usually harder than the front ( according to Oleg's findings and true calculations used by World Class drivers ). If you should push down on the front and rear on a "conventional TC" it should feel fairly similar or even softer in the front as Oleg has described. So, on the A700 conventional wisdom says to go with what the world champions do because it works for them. We just don't have to worry about the damper hitting the front tires so each corner has the same pickup point / or leverage point and therefore each corner is symmetrical. I hope I did an adequate job explaining it.

Jake D.

Last edited by Magnet Top; 01-28-2012 at 11:24 PM.
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Old 01-28-2012, 11:15 PM   #1476
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Originally Posted by Magnet Top View Post
Most "Conventional" TC's have the rear shocks lower pickup point further out ( compared to the fronts ( because the fronts need clearance for the tire to turn and not hit the shock )). So the rear shock/springs have more leverage compared to the fronts because they pickup further out. So softer springs are used in the rear to compensate for the difference in leverage. The end effect is the rear is usually harder than the front ( according to Oleg's findings and true calculations ). If you should push down on the front and rear on a "conventional TC" it should feel fairly similar or even softer in the front as Oleg has described. So, on the A700 conventional wisdom says to go with what the world champions because it works for them. We just don't have to worry about the damper hitting the front tires so each corner has the same pickup point available for the damper. I hope I did an adequate job explaining it.

Jake D.
Thanks Jake. Makes sense.
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Old 01-28-2012, 11:38 PM   #1477
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Thanks Jake. Makes sense.
NP ! When I come down there for the Reedy race I'm sure you'll have your car all dialed in and I'll be asking you for advice.

Jake D.
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Old 01-29-2012, 05:12 AM   #1478
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Successful setup from Patrick Hornum (mod. A-main at DHI CUP 2012) was added on http://awesomatix.com/download/.

Patrick's car:
Attached Thumbnails
Awesomatix EP Touring Car-patrick-hornum-russerbil.jpg  

Last edited by Oleg Babich; 01-29-2012 at 07:14 AM.
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Old 01-29-2012, 07:46 PM   #1479
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Is anyone else having some troubles getting your car to balance on all four corners? See attachment, showing my corner weights with 0 weight added. Left to right balance is great, within a couple grams. But my left front and right rear corners are about 30 grams heavier without the body, and about 35-40 heavier with a body, than the other side.

My only thought at this point is that the heavy corners happen to hold the ring side of the ring and pinion for both the spool and the gear diff.

Note: I've taken as many precautions as I can to ensure proper measurement. For instance, measuring with car forward, then car reversed to eliminate the levelness of the surface from being the issue. Also, I've set the droop at exactly 5mm all the way around, and then used set screws in the uptravel stops to secure the arm at that location. With setup wheels on, the car sits at 5.9mm ride height all the way around, and shocks are disconnected. I've also changed the setup to set shocks at 3mm for the A measurement, all the way around. Finally, I've loosened the top deck and just barely snugged down the top link ball studs, to ensure there's no tweak.

See photos at this URL of what I'm describing. Also, see attached spreadsheet image below.



I suppose this could simply be a matter of the battery to far back, second from rearmost position, and the electronics stacked too far forward, but my layout doesn't seem much different from any other pictures I've seen.


Thanks for any help you might provide.
Ethan

Last edited by erchn; 01-30-2012 at 10:37 AM. Reason: clarification on thoughts
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Old 01-29-2012, 08:05 PM   #1480
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Follow-up to previous. If you add lightweight body and tires (minus setup wheels) the car currently weighs about 1360g, so to hit close to 1380g, I have around 20g of weight to place.

Finally, yes, I can tweak things with ride height adjustment to get it closer, but I think that's not the right thing to do, even if it is effective.
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Old 01-29-2012, 08:21 PM   #1481
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Quote:
Originally Posted by erchn View Post
Is anyone else having some troubles getting your car to balance on all four corners? See attachment, showing my corner weights with 0 weight added. Left to right balance is great, within a couple grams. But my left front and right rear corners are about 30 grams heavier without the body, and about 35-40 heavier with a body, than the other side.

My only thought at this point is that the heavy corners happen to hold the ring side of the ring and pinion for both the spool and the gear diff.

Note: I've taken as many precautions as I can to ensure proper measurement. For instance, measuring with car forward, then car reversed to eliminate the levelness of the surface from being the issue. Also, I've set the droop at exactly 5mm all the way around, and then used set screws in the uptravel stops to secure the arm at that location. With setup wheels on, the car sits at 5.9mm ride height all the way around, and shocks are disconnected. I've also changed the setup to set shocks at 3mm for the A measurement, all the way around. Finally, I've loosened the top deck and just barely snugged down the top link ball studs, to ensure there's no tweak.

See photos at this URL of what I'm describing. Also, see attached spreadsheet image below.



I suppose this could simply be a matter of the battery to far back, second from rearmost position, and the electronics stacked to far forward, but my layout doesn't seem much different from any other pictures I've seen.


Thanks for any help you might provide.
Ethan
How far out is your battery? Having it too far out will affect one corner more than the other.

Having said that, I really don't bother too much with cross weights. Just balance it up on some screws so it sits level, then adjust the tweak.
Having a car with correct tyre loads is more important than having the ride-height the same left to right.. it's simply more critical to getting a car handling better, IMO.
Obviously, if there is a big difference then it would need tweaking, but obsessing too much over it and can lead to making compromises with the setup that adversely affect the performance. I'm not saying don't do it, but trying to get everything perfect can lead you to painting yourself into a corner on setup. The comment you make about the battery being too far back is a case in point there... If you find that you get perfect balance with the F2 position, would you then ever run the cells further back, even if they were faster that way?

HiH
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Old 01-29-2012, 08:41 PM   #1482
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How far out is your battery? Having it too far out will affect one corner more than the other.

Having said that, I really don't bother too much with cross weights. Just balance it up on some screws so it sits level, then adjust the tweak.
Having a car with correct tyre loads is more important than having the ride-height the same left to right.. it's simply more critical to getting a car handling better, IMO.
Obviously, if there is a big difference then it would need tweaking, but obsessing too much over it and can lead to making compromises with the setup that adversely affect the performance. I'm not saying don't do it, but trying to get everything perfect can lead you to painting yourself into a corner on setup. The comment you make about the battery being too far back is a case in point there... If you find that you get perfect balance with the F2 position, would you then ever run the cells further back, even if they were faster that way?

HiH
Ed
Battery is about 3mm from the center shaft bearing holder, hanging about 1mm off of the chassis, so pretty far in.

I never had intention of limiting my setup because of battery position, but do like to have good balance, and cross weights make me feel better due to ride height adjustment being much easier to measure. I figure a 30g difference between left and right tires at either front or rear is significant. I would like to get it closer to 10g, but I guess it might not be much, considering it's only probably a turn on each ride height screw to correct. Just feels dirty. ;-)

Thanks again for your advice.
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Old 01-29-2012, 11:06 PM   #1483
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Battery is about 3mm from the center shaft bearing holder, hanging about 1mm off of the chassis, so pretty far in.

I never had intention of limiting my setup because of battery position, but do like to have good balance, and cross weights make me feel better due to ride height adjustment being much easier to measure. I figure a 30g difference between left and right tires at either front or rear is significant. I would like to get it closer to 10g, but I guess it might not be much, considering it's only probably a turn on each ride height screw to correct. Just feels dirty. ;-)

Thanks again for your advice.
Haha, sorry if it came across a little harsh! Try moving the pack of cells in flush to the chassis edge if you can, might be surprised by it. I know when I was playing with balance before, even moving the cells 0.5mm L-R can really affect the car.

HiH
Ed
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Old 01-29-2012, 11:46 PM   #1484
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Haha, sorry if it came across a little harsh! Try moving the pack of cells in flush to the chassis edge if you can, might be surprised by it. I know when I was playing with balance before, even moving the cells 0.5mm L-R can really affect the car.

HiH
Ed
Didn't come across harsh, I understand.

Flush got me to about a 20g difference. Better, thx.

Ethan
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Old 01-29-2012, 11:57 PM   #1485
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Follow-up to previous. If you add lightweight body and tires (minus setup wheels) the car currently weighs about 1360g, so to hit close to 1380g, I have around 20g of weight to place.

Finally, yes, I can tweak things with ride height adjustment to get it closer, but I think that's not the right thing to do, even if it is effective.
How heavy are your electronics, mine came in at 1300g before adding weights.
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