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Old 11-07-2010, 04:35 PM
  #1216  
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my ch10 was the opposite it didn't come in until 3-4 min mark then i could hammer it out of a corner but by then i was down a lap
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Old 11-07-2010, 05:12 PM
  #1217  
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Originally Posted by HarryLeach
I can deal with the car if it goes a *little* loose toward the end of a run, but right now it feels like the front scrubs enough to put the brakes on, and the rear didn't get the memo.
I think you're right on the money here! I had the same issue and was able to tune it out. The car, however, now is "stuck" all the way through the corner. Very driveable, but has lost corner speed noticeably.

I think using the carbonfiber sidelinks will help match up the front and rear better. With the 12RR car, there was a marked improvement when we all changed from the white fiberglass "hockeysticks" to the carbonfiber part instead. With that car (and the fiberglass sidelinks) it would loop pretty easy if the front and rear weren't coordinated well. I think the fiberglass piece has a more linear spring rate and the carbonfiber is a more progressive spring rate. The carbonfiber pieces on either car should make coordinating with the front setup a much wider target.

As I've gotten older I realize I have learned a lot of this stuff over the years, just have trouble remembering what it was sometimes.
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Old 11-07-2010, 05:49 PM
  #1218  
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The problem with running the pink rears is that up front for the first few minutes, it will feel ok but in reality, they grip a lot because they have allot of natural rubber in them and they push the front end through the corners. This is what gums up the fronts. As mentioned, Jaco orange, BSR gray/white or CRC graylow are the ticket.They are all equivalent to each other. They wont push the front on power. I have to say the pinks are about 90% of your problem. From there, you can reduce your camber gain by shimming the hinge pin block up 1mm. That should get you where you want to be.
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Old 11-07-2010, 05:55 PM
  #1219  
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Originally Posted by odpurple
The CEFX Griffin 12 uses the same motor mounting design and the pod plates are aluminum. The car has been out for a while now and I've heard no reports of problems with the plates
It will work. My concern is that the mounting screws are so close together and only on one side of the motor. It looks as if the motor will have an easy time bending the pod in an impact from the leverage. I could be wrong but time will tell. Everyone has different ideas of how cars should be. If we didnt it would be a pretty boring class as we would all be running the same thing. Oh wait, that would make 1/12th just like TC. Oh please no!!
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Old 11-07-2010, 05:57 PM
  #1220  
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Originally Posted by VRacing
I think you're right on the money here! I had the same issue and was able to tune it out. The car, however, now is "stuck" all the way through the corner. Very driveable, but has lost corner speed noticeably.
I'll even take that for the time being! I was many laps off the pace Saturday, and just did what I could to get out of the way after spinning in front of the leaders, because the car just WOULD NOT stay straight. I even dialed out steering rate the whole race, started out around 70%, ended around 45%, and I still had to be extra soft on steering and throttle input to nurse the car around the track.

Heck, I'll take traction rolling right now over what it's doing!

I know it's as much me not driving the car as well as I know I could as it is car setup, I just need a LOT more rear traction throughout 8 minutes, or get rid of a lot of front grip. Once I can make 8 minutes on a relatively clean run, then I'll start looking to free the car up and get faster.
I think using the carbonfiber sidelinks will help match up the front and rear better. With the 12RR car, there was a marked improvement when we all changed from the white fiberglass "hockeysticks" to the carbonfiber part instead. With that car (and the fiberglass sidelinks) it would loop pretty easy if the front and rear weren't coordinated well. I think the fiberglass piece has a more linear spring rate and the carbonfiber is a more progressive spring rate. The carbonfiber pieces on either car should make coordinating with the front setup a much wider target.
I'm already using the 1.5cf links. They did seem to help lock in the rear a little more than the fiberglass links, but I didn't get enough meaningful testing on decent grip with the 1.2cf links to know from testing if the 1.5's are too stiff and actually hurting. I suppose I'll try the 1.5's in the short position when I get a chance to test this week, and that should give me an indication if I'm too stiff on the rear links or not.

Some of the online setup tips for 1/12 seem a little contradictory. On one of the same guides I read over, it says stiffening the rear generates more side bite and rear traction, and then goes on to say the general rule is stiffening the rear adds steering.

As I've gotten older I realize I have learned a lot of this stuff over the years, just have trouble remembering what it was sometimes.
I hear ya, I've definitely been out of pan cars too long, I can't remember what's what, and testing every possibility on my own isn't an option with my work and race schedule. At the moment I don't seem to even be in the ball park, so winning the game presents a bigger-than-average challenge

Last edited by HarryLeach; 11-07-2010 at 06:11 PM.
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Old 11-07-2010, 06:00 PM
  #1221  
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Originally Posted by protc3
The problem with running the pink rears is that up front for the first few minutes, it will feel ok but in reality, they grip a lot because they have allot of natural rubber in them and they push the front end through the corners. This is what gums up the fronts. As mentioned, Jaco orange, BSR gray/white or CRC graylow are the ticket.They are all equivalent to each other. They wont push the front on power. I have to say the pinks are about 90% of your problem. From there, you can reduce your camber gain by shimming the hinge pin block up 1mm. That should get you where you want to be.
I appreciate the feedback, looks like I'll be picking up some rear tires and having a full day of testing this week.
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Old 11-07-2010, 06:05 PM
  #1222  
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I run my new front standoff set on mine that are 2mm higher. Really tones the car down.Adding camber increases front grip as does alot of camber gain. Reducing both will mellow the front down.
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Old 11-07-2010, 06:10 PM
  #1223  
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I have the taller standoffs as well, but when I first tested with them, traction was too low to evaluate one way or the other.

I still think the 1.5 front links are too soft for our track, but I'll find out more this week.

I appreciate everyone's input, and I'll report back after testing later this week.
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Old 11-07-2010, 06:28 PM
  #1224  
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The 1.5mm front plates may be too soft for your conditions. Try the 1.8mm in soft position. I have run them and i do like them. I go back and forth according to track conditions.
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Old 11-07-2010, 06:35 PM
  #1225  
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Originally Posted by protc3
The 1.5mm front plates may be too soft for your conditions. Try the 1.8mm in soft position. I have run them and i do like them. I go back and forth according to track conditions.
I will as soon as I get them after you send out my order Monday
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Old 11-07-2010, 06:38 PM
  #1226  
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Originally Posted by avs
time will tell, but the pod strength may be deceptive, as you know a short load path produces less moment, and its the moment that bends things. the rear pod height adjustment looks convenient for fine tuning, i would expect top to make different bearing holders for coarse adjustments, maybe a carpet and asphalt specific part set? the bearing holder looks to be engaged on 2 sides by the pod sideplate, so this may be better supported than it appears. also the cross tube should bear on the outer race support, and this tube diameter may also be deceptive, because of the additional bending rigidity. the tube wall thickness is probably driven by buckling, and bending rigidity is more than adequete.

note these are just observations, not a firm opinion for or against.
If the pod tube rests on the outer part of the bearing, then it will pretty much be almost a pry for pulling the bearing apart as the hubs rest on the inner diameter. Even at that, the majority of the load will be transferred to the plastic holder which look to be the weak link. Breakage aside, under a side impact, the bearing holders can slip and this will get easier to do the more you shim it up. As for the pod bending, its the small mounting area that worries me. I have seen all of the current pods bend. Even with the massive reinforcements. The motor is long and heavy and in an impact, wants to keep in its forward motion. Small surface mounting area and the screws being so close together and only on one side of the motor, to me, is just asking for destruction. I havent seen it in person so i will just have to wait and see if my observations are correct.

I am going to be working on a new style of ride height adjustment. This style is not it. It is interesting and i take my hat off to them for trying it out.
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Old 11-07-2010, 06:54 PM
  #1227  
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What about wheels or upper arms J? Ever thought about them? j/k
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Old 11-07-2010, 10:35 PM
  #1228  
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Some of the online setup tips for 1/12 seem a little contradictory. On one of the same guides I read over, it says stiffening the rear generates more side bite and rear traction, and then goes on to say the general rule is stiffening the rear adds steering.
Because carpet is soft and cushioned, most people don't consider that they are bottoming out the chassis. Touching down is much less apparent than banging it of asphalt. What happens is that as you increase the stiffness of the center spring gradually, the car stops touching down and you get more rear bite. As you reach the point where the car no longer drags, the normal laws of tuning return, and further stiffening of the center spring results in more steering. For most cars this appears to happen around the level of the gold spring. undoubtedly why so many people run them.
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Old 11-08-2010, 06:18 AM
  #1229  
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Originally Posted by EricF
Ferrari. No wonder I cant afford the new model I need something in the Mustang GT500 or corvette range
E
Not saying my cars are for everyone. Most all of the companies went for the low price tag and let you bring the price overboard in aftermarket parts. I decided to include it all and also go with quality instead of dropping all of the quality and boasting a low price tag. If you price out any of the other cars and then the upgrades needed to make it comparable, you are exceeding the price of our car. We didnt go to molded pods,standoffs,cheap C/F, and steel turnbuckles ect so we can drop the price. I went with making the best possible car i could and this costs more. For those who just want inexpensive, our car is not the one for you. There are cheap cars out there for those people. Just keep in mind,as with anything, you get what you pay for.
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Old 11-08-2010, 06:21 AM
  #1230  
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build it once and build it right
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