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Old 09-22-2010, 10:51 PM   #1681
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I have tried the trailing axle. I find that it trails too much and does not act like the associated trailing axle which only trails 1/8 inch. A trailing axle adds some caster and does reduce nervousness on corner entry.

This corner exit problem is a thorny one as the cause is debatable.
Some things that seemed to help me.
A longer wheelbase.
A little more pod droop.
You say it happens before throttle application, but maybe a little more delay in throttle application is what you need.

Your front tires should be fine, but Jacos run a little harder than the rest so maybe a Jaco spec front or another brand of softer purple may help.

I actually think the fronts let go when this happens and the outside rear drives the car into the inner boards.
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Old 09-23-2010, 07:28 AM   #1682
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I have always run trailing on a 200mm car with GT shell, but the my track is high traction.
I had the hooking problem bad when running the Mulsanne shell as it produced way to much rear downforce causing you to use more steering in a corner, which then hooked the car once the power was applied coming out of a corner (not even a full coat of additive could cure this).
You may need to loosen the rear to make sure you use less steering in corners, this will then reduce the hooking effect, or change to a shell with more front bite, turn down the steering, and set the car up to be balanced with that shell.
Outdoors with 200mm GT shells on my high bite track the PF Corvette is best, but on a lower bite the Sophia is better. Only use the Mulsanne if indoor on high bite carpet (or if you are running a Tamiya F10? model).
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Old 09-23-2010, 01:02 PM   #1683
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Maybe removing some rear traction is worth a crack. We are low/medium traction asphalt with no additive allowed. Last race meet there was a nice thick layer of pollen we had to drive off the track for the first few rounds.

If I increase rear pod droop, will that give more on-power rear traction?
I may also try stiffer side springs. I currently use white in the back, may give reds a go.

Also,y diff may have been a tad tight last race which would not have helped the end-swapping.

Thanks for the ideas guys.

This isn't deterring me one bit. I'm having so much more fun with pans than my TC, even though there are only a few guys to race
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Old 09-24-2010, 09:13 AM   #1684
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Quote:
Originally Posted by John Stranahan View Post
Front downforce is almost impossible to increase without some under car device like a diffuser. One thing is for sure the wedge body has less cross-sectional front area so it can normally attain a higher speed, but not necessarily more downforce than a sedan body.
Taking a note from the WRC, Nascar, and even the slot car guys. A front splitter can provide lots of downforce. Changing the length of the splitter changes the amount of front downforce.

I'm still reading about your other adventures, with your inerter, did you ever consider that a better shock might cover that entirely?

I sitll have 30 pages to read to catch up...... ;-)
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Old 09-24-2010, 09:44 PM   #1685
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Not sure if i've asked this before, but how much droop would you have for an outdoor asphalt set-up?
I got told to have zero, which is what I did, but then in the garage I was having a play and noticed this:
When I push down on the side-spring to the point of the chassis corner touching the deck, the opposite front wheel lifts off the ground.
I know normally there wouldn't be that much down travel on the chassis, but thought perhaps with no front droop, the inside wheel is lifting causing the hook.
I've added about 1 to 1.25mm droop and hope to get to the track tomorrow.
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Old 09-25-2010, 01:41 AM   #1686
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I have been running with no front droop, but have had about 2mm of rear droop.
Running no front droop takes away some of the steering, so if you are finding a lack of steering on fast corners and going in to corners then add some droop.
It does not directly cause the hooking effect, but if you are having to use more steering in corners then THAT will cause the hooking.
You need to find that balance between the amount of steering you use and cornering grip, maybe even running a different racing line so you enter a corner sharper but exit straighter.
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Old 09-25-2010, 02:04 PM   #1687
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im getting the first crc 10th pan car, whats needed to update it to the new car?
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Old 09-25-2010, 06:14 PM   #1688
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Originally Posted by D-Bizzle View Post
im getting the first crc 10th pan car, whats needed to update it to the new car?
What do you mean by new car the genx le car? Because I have a first genx and love it run it in wgt with 1s and have another tray that if I want I can put a 2s in it.
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Old 09-26-2010, 02:39 PM   #1689
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Well, out for practice yesterday (once in a blue moon chance). Was also with a friend who has an X-Ray X-10. The track was dusty as usual, but his car was driving well, and mine was again poop.

I know all cars are different, and require different set-ups, but his front was harder than mine (yes we got a laugh out of that too), and his rear was a lot softer in the centre shock, and similar side-to-side.

I'm going to go right back to scratch and build the car from the ground up again. Part of the problem is having 2-cell lipo with 13.5 on a dusty asphalt track with no tire additive allowed is always going to be a challenge.

This is what I have:
Front:
Jaco Purple
long wheelbase
Medium width
Red springs
caster shims 2 back, 1 front
5 Reactive caster

Rear
Jaco Pink
Centre shock white tamiya spring (about 15lb), 35wt
8000wt Damper tubes
White side springs

Ride height is 7.5mm all round

She weighs just on 1200 grams race ready to meet our minimum requirements. That is going down to 1115 in a few months.
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Old 09-26-2010, 02:46 PM   #1690
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Quote:
Originally Posted by JR007 View Post
Well, out for practice yesterday (once in a blue moon chance). Was also with a friend who has an X-Ray X-10. The track was dusty as usual, but his car was driving well, and mine was again poop.

I know all cars are different, and require different set-ups, but his front was harder than mine (yes we got a laugh out of that too), and his rear was a lot softer in the centre shock, and similar side-to-side.

I'm going to go right back to scratch and build the car from the ground up again. Part of the problem is having 2-cell lipo with 13.5 on a dusty asphalt track with no tire additive allowed is always going to be a challenge.

This is what I have:
Front:
Jaco Purple
long wheelbase
Medium width
Red springs
caster shims 2 back, 1 front
5 Reactive caster

Rear
Jaco Pink
Centre shock white tamiya spring (about 15lb), 35wt
8000wt Damper tubes
White side springs

Ride height is 7.5mm all round

She weighs just on 1200 grams race ready to meet our minimum requirements. That is going down to 1115 in a few months.
Have you tried reducing the punch on the ESC?
I can loose the rear under power with a 17.5 / additive / and a high grip track, so a 13.5 on a dusty track with no additive is slightly asking for trouble.
Try delaying the boost to give you a chance to get the car straight before the power come in, and possibly increase the motor timing to reduce torque.
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Old 09-27-2010, 07:44 PM   #1691
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Jr007-Try a BSR pink rear or RC4less pink rear. You will pick up some rear cornering traction and get more forward traction. Keep the center spring just hard enough to keep the chassis off the ground.


Just a couple of pics. New body with front diffuser bolted on. My Scimitar spec (all except the new chassis) wide pan prototype. I should get a chance to run it this next weekend. Note that this new Scimitar has a custom wide pod. It uses a standard wide pan right hand hub. It has full top plate for much better motor support.

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Last edited by John Stranahan; 09-27-2010 at 07:54 PM.
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Old 09-28-2010, 04:19 PM   #1692
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That is a very nice looking car John!
One day when I win the lottery i'll be placing an order! (Or stop having kids, they drain the bank account too fast).
I'll order some of those tires. Have you (or anyone) tried the Exceed foams? Not sure if they are Jaco or BSR type, but they were on the other car.
This is a sketch of our track. As you can see, it's a beast. Race is direction clockwise. We use the cut-through towards the end of the straight as a hairpin, and have the longest route for the rest of the track. The back straight is about 70m on the racing line, that's over 200 feet for you guys on the other side of the pacific!
http://www.crccc.co.nz/MyImages/SCAN3303_000.pdf
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Old 09-29-2010, 08:47 AM   #1693
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That is one long straight.
Ours is only 155ft (45m)
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Old 10-05-2010, 11:39 AM   #1694
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Was just looking at my set-up, and there was 1 thing I haven't asked. Where is the ideal position for the servo? I'm running it at present so the steering rods are in-line when looking down. Not sure how ackerman works on a pan car, is it the same as touring? Should I run it forward a little to increase the ackerman?
Looking at the front of the car, the rods angle up a fair bit, but I can't notice any bump-steer when I compress the front suspension, so I assume that's fine.
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Old 10-05-2010, 02:24 PM   #1695
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Never played with ackerman
My Savox 12th scale servo is as far forward as possible, and uses the Kimbrough Medium servo saver and uses furthest holes from servo screw
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