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with puma weights we could end up with a COM at or even less than 1/2"
we need to add 3 more tungsten cubes to hit 5 oz ... if we put them near the axle then the COM will be inside the diameter of the puma weights themselves (making it hard to measure)...or we could slide them forward and have a COM at or over 0.5"
Track is an aluminum track. Any advice appreciated!
Whoo, you're getting into Sporty/Noskills territory, now.
I'd be personally apprehensive without having a test track, in order to catch/diagnose possible rear-end waggles. However, other folks without a test track have gone 3/8 COM and had success, so I'll let them chime in.
I aim for exactly 0.5 but would take 3/8 th if I could get it. If using 3/8th would really dial up the drift to 4 inches over 4 feet even with an extended wheelbase.
Noskills
"Nunchuk skills... bowhunting skills... pinewood derby skills... Girls only want boyfriends who have great skills!"
Napoleon Dynamite
I measured how much weight would be on the DFW. Since we can move the 3 weights we still need to place into any of the pockets forward of the rear axle, we could adjust the COM / weight on DFW. Since the COM is less than the diameter of the puma weights, I thought I'd show the weight on the DFW for comment.
So, for a given ____ placement, the weight on the DFW would = ____ as follows:
as close to rear axle as possible = 0.452 oz
forward part of pocket that is just in front of axle (as in the picture) = 0.481 oz
Those who tune with a raised tuning board, naturally the drift would be different. car go faster, go steer faster to the rail or the drift.
So the flat level tuning for drift method, the car is moving slower, just a roll really.
Its likely the raised tuning method is better.
Its just something that I started with and worked with and stuck with it. It has worked well for me. But it may not for others. Its also at times. why I have to mention this, When people ask for a drift number.
For me, the car rolling slower, I am able to look for other things, mild wiggle, shimmy, if I see any issue with the front axle, like effecting the DFW hub, how it steers over, suddenly ? a nice smooth drift. things like that. For me. I see them better that way.
Some worry the push or shove to get rolling is more risky and not done just right, can effect the cars actual real drift.
I do not think my way is the best way in this area, that's for sure, its just what works 4 me.
Unless you have a track to tune on, I wouldn't recommend a COM under .5in.
Please note, the following is my best guess based on experience. But, just from that picture, I predict you'll have some serious wiggle. You need to get some weight on your DFW. So I'd put one of those cubes behind the front spar to the far DFW side, and the other two cubes in front of the spar to the far DFW side.
Then give the car at least 4" steer over 4 feet. I might go 4.5 - 5. Don't fear the steer! Over-steer only costs you a little. Under steer (and wiggles) will cost you a lot more.
The push off was my first concern when I read you use the floor. I actually change the height of my incline depending on what I want to check. A slow roll I will keep it sloped just enough to get rolling. For steer I go higher to get the speed up slightly. I also add a meter stick and run it a few times to watch how the back wheels behave once the DFW is set up on the rail.
I am thinking of making a short test track to try to get the speed up more to see if I can cause the same wiggles I have been getting on the real track so I can try to tune them out. I have been getting inconsistent results so far depending on which lane it is in.
sporty wrote:Those who tune with a raised tuning board, naturally the drift would be different. car go faster, go steer faster to the rail or the drift.
So the flat level tuning for drift method, the car is moving slower, just a roll really.
Its likely the raised tuning method is better.
Its just something that I started with and worked with and stuck with it. It has worked well for me. But it may not for others. Its also at times. why I have to mention this, When people ask for a drift number.
For me, the car rolling slower, I am able to look for other things, mild wiggle, shimmy, if I see any issue with the front axle, like effecting the DFW hub, how it steers over, suddenly ? a nice smooth drift. things like that. For me. I see them better that way.
Some worry the push or shove to get rolling is more risky and not done just right, can effect the cars actual real drift.
I do not think my way is the best way in this area, that's for sure, its just what works 4 me.
