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Old 09-16-2010, 01:42 PM   #481
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OK Darkside here is my setup. This is for a small,50x30, track. This is a work in progress, but it hooks up well on our track. I have the CF chassis and shock towers installed. The main chassis was a huge improvement over the plastic chassis.

FRONT
Ride Height - 5mm
Droop - 1.5mm over ride height
Caster - 4*
Camber - -1.5*
Toe - 0*
Upper control arm - E
Shock location - 3B
Springs - HPI Pink (15.2#)
Oil/Piston - Trinity30/2 hole
REAR
Ride Height - 5mm
Droop - 1.5mm over ride height
Camber - -1*
Toe - -3*
Upper control arm - C2
Shock location - 3[COLOR="Red"]A
Springs - HPI Orange (12.1#)
Oil/Piston - Trinity30/2 hole
Made a couple changes to this setup and the car is a blast to drive now. Changes are in RED
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Old 12-10-2010, 12:41 PM   #482
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Took me 3 days but I've finally read all 33 pages. Tons of great info.

I just started VTA. Our track is small with many switchbacks and only one fast sweeper. I bought a used TC5 that was (sort of) set up for VTA. The car started out like the back tires were made of glass. Like driving a drift car. Borrowed some tires for my first race day. Better. I now have two sets of prepped tires. Still breaking them in as they gum up within two minutes. Starts out wicked fast with great steering and rear traction. 2 minutes later, ice rink handling. Still working on it.

I've cleaned, doped, bagged the tires between race days. I think they are too soft so I've left them dry and will see how they do. I'm also going through and changing the chassis to better suit VTA IAW the set ups I've read here.

Current set up: blue front/silver rear springs with 50wt oil, 1.25mm front sway, 5mm front and 6mm rear right height, 3A arm mounts, mid high front cam, low rear cam locations. I have a camber gage, ride height and droop gage waiting for me at the LHS. Also need to check which front castor blocks or on it.

I think the rear belt is too tight so I'll install the same cam holder as what's in the front and adjust belt accordingly. Also need to change springs to silver/green and swap to 35wt. I think I'm overheating the tires which isn't helping the goo factor. I'll try 4* castor if it's not there now, otherwise may try 6.

When it's hooked up, it's fast. So much fun.
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Old 12-10-2010, 01:52 PM   #483
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What's the track surface?

And i agree on the oil, 35 is what i've used on a tight concrete track.

Something else to consider, ball diffs front and rear. I like that better for tight tracks.
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Old 12-10-2010, 10:23 PM   #484
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Took me 3 days but I've finally read all 33 pages. Tons of great info.

I just started VTA. Our track is small with many switchbacks and only one fast sweeper. I bought a used TC5 that was (sort of) set up for VTA. The car started out like the back tires were made of glass. Like driving a drift car. Borrowed some tires for my first race day. Better. I now have two sets of prepped tires. Still breaking them in as they gum up within two minutes. Starts out wicked fast with great steering and rear traction. 2 minutes later, ice rink handling. Still working on it.

I've cleaned, doped, bagged the tires between race days. I think they are too soft so I've left them dry and will see how they do. I'm also going through and changing the chassis to better suit VTA IAW the set ups I've read here.

Current set up: blue front/silver rear springs with 50wt oil, 1.25mm front sway, 5mm front and 6mm rear right height, 3A arm mounts, mid high front cam, low rear cam locations. I have a camber gage, ride height and droop gage waiting for me at the LHS. Also need to check which front castor blocks or on it.

I think the rear belt is too tight so I'll install the same cam holder as what's in the front and adjust belt accordingly. Also need to change springs to silver/green and swap to 35wt. I think I'm overheating the tires which isn't helping the goo factor. I'll try 4* castor if it's not there now, otherwise may try 6.

When it's hooked up, it's fast. So much fun.
You must make the car as soft as possible. I ran on a track with the same conditions. You may even want to go to 25 wt oil. Ditch the sway bars. 4 caster. If you can find some stupid soft springs, like the flourescent mini car set Tamiya makes, that may help as well.
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Old 12-11-2010, 12:22 PM   #485
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Announcing VINTAGE LATE MODEL at Trackside

http://www.rctech.net/forum/8328649-post449.html
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Old 12-12-2010, 12:57 AM   #486
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Originally Posted by want2race441 View Post
Took me 3 days but I've finally read all 33 pages. Tons of great info.

I just started VTA. Our track is small with many switchbacks and only one fast sweeper. I bought a used TC5 that was (sort of) set up for VTA. The car started out like the back tires were made of glass. Like driving a drift car. Borrowed some tires for my first race day. Better. I now have two sets of prepped tires. Still breaking them in as they gum up within two minutes. Starts out wicked fast with great steering and rear traction. 2 minutes later, ice rink handling. Still working on it.

I've cleaned, doped, bagged the tires between race days. I think they are too soft so I've left them dry and will see how they do. I'm also going through and changing the chassis to better suit VTA IAW the set ups I've read here.

Current set up: blue front/silver rear springs with 50wt oil, 1.25mm front sway, 5mm front and 6mm rear right height, 3A arm mounts, mid high front cam, low rear cam locations. I have a camber gage, ride height and droop gage waiting for me at the LHS. Also need to check which front castor blocks or on it.

I think the rear belt is too tight so I'll install the same cam holder as what's in the front and adjust belt accordingly. Also need to change springs to silver/green and swap to 35wt. I think I'm overheating the tires which isn't helping the goo factor. I'll try 4* castor if it's not there now, otherwise may try 6.

When it's hooked up, it's fast. So much fun.
I am wondering if when you are saying "ice rink handling" do you mean the rear is loose and snaps around in a turn or does it push/slide nose first into the boards on a turn?

It could be the front and rear "balance" of the car. Not the weight distribution, but setup balance... like the roll centers & inner camber link location. If after a few minutes of racing the car gains too much traction in the front but not the rear and the rear is loose in the turns off throttle then it may need to have less front grip.

If it slides nose first into the outside board then check for proper differential action front and rear making sure they are not to tight and do not have any high spots or stick or bind when turning.

As for tires. I've seen people over treat VTA tires with additive including bagging them between races causing them to balloon up and not work well. They should look the same as you mounted them for the most part, slightly rounded and the tread should wear evenly for the most part.
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Old 12-13-2010, 10:17 AM   #487
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I am wondering if when you are saying "ice rink handling" do you mean the rear is loose and snaps around in a turn or does it push/slide nose first into the boards on a turn?

It could be the front and rear "balance" of the car. Not the weight distribution, but setup balance... like the roll centers & inner camber link location. If after a few minutes of racing the car gains too much traction in the front but not the rear and the rear is loose in the turns off throttle then it may need to have less front grip.

Icerink handling is the rear end. With clean tires the grip at both ends is amazing. After two minutes the rear traction drops off to near zero. The tires have substantial build up on them. The front lasts 5 minutes, but the rear only 2. It's loose on entry and exit, but entry is the hardest to control.

I made a make shift balancer to check left and right, using the chassis holes. It was way off with the battery I was using. The chassis has a ton of add on balast, but it was set up for the other battery (a 4900) that came with the car. The 3600 I was using is too light. I'll run the 4900 and the left/right balance will be very, very close. I haven't checked front to back, but the track has a two-scale set up and I'll weigh both front and rear on tuesday.

The front sway bar brackets are loose enough that I don't think the front bar is even doing anything. I'll ditch it.

I'm now running the mid-high diff holders F/R, it had a mid-high front and low rear before. It has the 4* castor blocks up front so I kept them. I may try the 6's if it's still really loose. My camber gage and ride height/droop gage came in. I'm going to start with 2* front and 0* rear camber, 5mm ride height with 4 and 6 droop (F/R).

Lastly, the track surface is well used carpet. Can't remember what it's actually called, but the racing line has a lot of rubber laid down. Once off the line the track is like marbles. Just like a full size track. Although with clean tires I can drive it anywhere, adjust mid corner if needed, full throttle exits and hard brake entry. I did try to soft shoe it around last time out and it still only lasted 2 minutes before I was just "in the way".

I'm most curious about my change in tire prep. No dope after cleaning. I can always juice them at the track but I want to see how long they stay clean when run dry.
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Old 12-13-2010, 11:30 AM   #488
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The 35wt oil and green springs in the rear should make a huge difference. I run that all the way around on my TC5

50wt is really pretty heavy oil for VTA, I only thicken it up front if a traction roll develops.
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Old 12-13-2010, 08:03 PM   #489
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One question about setting droop. I have the ride height at 5mm front and rear. My ride height gauge goes up to 8, then flip it on it's side it starts over from one and goes up. The one is the same as the 7 on the ride height (7mm). To get a droop number of 6 in the rear I put the chassis on the 4 of the droop gage part (the number 4 is 11mm thick). That is 6mm above the 5mm ride height. The rear tires are just touching. Is this correct for 6mm of droop/uptravel?

I had 6 in the front too, I reduced that to 4.

Either the car is going to be better or absolute crap since I changed so many things at once.
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Old 12-15-2010, 06:27 AM   #490
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Traction roll, heh I wish I had that kind of traction.

Tested last night. Ran with clean, dry tires to see how long they would go before gumming up. About 3 minutes. I wanted to test them without sauce. With sauce they last about the same but have higher grip.

The back end wants to come around on corner entry. I tried the 1.5mm swaybar to see if I could reduce that some. It did, slightly, but my mid corner steering went away. Crap. Took it back off when I got home.

Changes:
1B rear camber link, removed 2mm spacer from arm. 1* anti-squat in rear. 3* rear camber. Back to 3* rear toe (still using 0* at arm). I have some bump steer too. When I compress the front end it goes from 0 toe to 1* toe in. Steering links on the forward, inside holes. This is the least ackerman setting.

Would running less droop help the corner entry traction?

My rear diff seems really loose compared to my xxx-t diff. If it's too loose could the inside tire be spinning up too much causing my gum up issue?
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Old 12-15-2010, 06:39 AM   #491
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Loose on entry typically means too much steering.

In this order i'd try...

Dial out dual rate on your transmitter (can you do this?)
Softer rear springs
Heavier front springs
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Old 12-15-2010, 08:47 AM   #492
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I can dial out the steering rate. I'll try that.

I'm running AE Silver front and green rear springs. I can try to bump back up to the blue fronts.

I'm curious what the effects of lighter fluid are on the VTA tires. I would think that the high flash point would dry them out. Then adding tire dope would soften them up again. Guys at my track use motor/brake cleaner. Same type of thing, high flash point. I think fighting the tire build up is my biggest issue right now. Do the tires need to be worn down to reduce the tread depth, or just scuffed to get the release agent off. I've tried burning them down on my street and it just cleaned the carpet goo off. Streets covered in snow right now so I can't repeat the process for a while.

The build up is pretty thick, I use a water based gun cleaner (cuts carbon and dirt but safe for rubber) and a SS wire brush to scrape it off. Then a rag to remove the rest down to bare rubber.

I'm going to research the effects of front and rear roll centers. As well as increasing front caster.

Thanks for the help so far. It's frustrating that I can't get it to come around and just drive around the track like everybody else. Other cars squeel around the corners they have so much traction.
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Old 12-15-2010, 06:23 PM   #493
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Old 12-15-2010, 07:13 PM   #494
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Did you go to 25 or 30wt oil?

If your tires are squealing, you are breaking the car loose. You are heating the tires up since it's starting to slide. Normally, that can work fine, but you are picking clag off the track.

Just use motor spray to clean the tires. If you are getting a build up, drying the tires out a bit can only help. Clean tires are more important. Also, what traction compound? If you're using something weird, that may be part of the problem.
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Old 12-15-2010, 10:52 PM   #495
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Thanks for all the help gents. PM's appreciated. Sorry I've been long winded in my posts. Tearing down the chassis to make some changes. Noticed I have a diff in the front and rear. I bought the car used. I had gone through it as far as settings but now I'm going through it completely. I ordered a slipper spool, flex top plate and some other small parts.

I'm using Jack the Gripper. It's what's on the track already. I 2nd day air'd the spool, hopefully it will be here by saturday. I'll still run if I don't get, I'll leave it loose.

Edited after saturday's race day:

My VTA tires FINALLY came in. I don't know if it was just time, or my new cleaning method. I don't think I was getting the tires clean enough before. Brake cleaner, then doped them twice, then bagged them. The tires finally got shiney today. Car was glued, relatively. Even lasted the 8 minute A main without dropping off too much. I'm now within 2/10ths of the fast lap times. Corner speed is really good. Front end is diffing a bit, spool didn't arrive yet.

Here's what's working for now:
3B front shock location, 3B rear shocks, 25w oil, Silver front and green rear springs. 3A/3A control arm locations on the front. 3A/2A on the rear (anti-squat). Rear arms all the way forward. Front arms 1mm spacer in front. Camber rod front, 3. Camber rod rear, 3B (outer hole on hub). 3* of rear toe, per side (thick and thin arm spacer). 2* front camber. 3* rear camber. 6* castor block. Enough spacers to keep bump steer as close to zero as I could get it. Front/outer holes for steering link. 5mm ride height. 4mm/3mm droop f/r.

Car is pretty neutral, just a hint of on-power understeer. Has good turn in without stepping out. I can catch it if I step it out on the brakes or out of the groove. Gearing was right in the middle of allowable range. I stepped up one tooth on the pinion, my motor temps were around 78* after 5 min. It was a little flat, but I need to retest with a fresh battery, I was 12 minutes of run time on a 3800mah pack. I was able to get 3 8.8 second laps, were as my previous best was 8.6 with the smaller pinion and fresh battery.

I'm just glad the thing is drivable finally. My Exotek chassis arrived and my spool and alum diff will be here monday. Can't wait to test again.

Last edited by want2race441; 12-18-2010 at 09:25 PM.
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