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Old 07-07-2010, 06:22 PM   #11416
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Where on the site are these deals found? That site really needs a search function. I see the TC3 parts but no special sale items.
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Old 07-08-2010, 04:20 PM   #11417
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Post# 11414 updated.
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Old 07-08-2010, 05:38 PM   #11418
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Originally Posted by Timbulb View Post
Where on the site are these deals found? That site really needs a search function. I see the TC3 parts but no special sale items.
If you click the link, you'll see the page where the parts are found. You could also go to the closeout link on the main shopping page

The prices have been changed to reflect the sale.

For example, the titanium universals used to be $59.99
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Old 07-26-2010, 10:33 AM   #11419
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Hello everyone.

For those who are interested, I found a fairly decent way of giving the front A-arms some inboard toe-out. I could not go further to try and explain why it is so nice to have some, but my xray and HB both loved to have at least 1,5 degree per side. The front end feels soooooo good with this. The HB car comes with 2.5 degrees out of the box, BTW. The XXXs was the first car to feature angled front inner hinge pins if I remember well.

I have not tested it yet on my TC3 but I am confident it will feel as good as on the other cars.

You just have to use a R+3+2 hinge pin holder instead of the F-0 holder. It will give you a F+1.5+0. You'll need a little bit of dremel work and 2 new screws (longer and /or of a larger diameter- I put some M3), but it fits nicely overall. Just shorten 0,2mm of the 2 bits that go through the bumper. Sorry again for my approximate English ! If you need details just ask. Dave W your info is interesting, thanks.
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Old 07-29-2010, 10:30 AM   #11420
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Correct me if i'm wrong but would tightening up your front diff give you the same effect as running a tc5 slipper spool?
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Old 07-29-2010, 10:47 AM   #11421
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Not really. It's hard to explain the mechanics of it, but the slipper spool has a very different feel from either a diff or solid spool. I built one for my Diggety XLR-8 and the car has never handled as good as it does now.
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Old 07-30-2010, 01:32 PM   #11422
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MMMh, I agree that a very tight diff is and feels different from a spool, but if you feel a difference between a solid spool and a slipper spool, the latter is likely too loose.

A quick update about my mod, I had the chance to run my TC3 on asphalt with the front inboard toe-out, and it is simply awesome. I highly recommend it, to any tournig car owner, it makes the car really nice. I really can't imagine nor discribe the effect, but the feeling is great. I had left my LCS home, but the track was slower than usual anyways, due to pollen/dust; so I wouldn't have been able to compare lap times with the usual sugared track.

If anyone here wants to test it and give me his feedback... it's only a 20 minute modification.
I can post my setup if anyone's interested, it's surely not perfect but more than decent. A guy at the track who has a bit less skill than me, tried the car and he was on the line after less than a lap. He said thank you several times after that.
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Old 07-30-2010, 01:48 PM   #11423
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Quote:
Originally Posted by DaveW View Post
Years ago i used to lower my servo into either a Tc3 or Tc4 chassis (same for my B3/T3 and battery slots in those chassis). It caught on and became a fairly popular mod. Most did it to lower the CG of the car. I did it for that AND to correct the poor geometry of the steering servo to steering rack link.

With the past few chassis i have modded, i have chosen to avoid lowering the servo to preserve its structural integrity in hopes of consistent torsional flex.

The following mod to the standard servo arm maintains equal left to right throw on the transmitter (with the arm one tooth off center per instructions), and mimics the servo being lower in the chassis for this purpose. No more 94%-62% EPA settings for lock to lock steering. This is important for steering balance and consistent feel left to right.
I don't really understand this modification...

I have found the steering to be very symmetrical when the stock servo arm was placed at a 90 degrees angle with the steering link-its lenght being adjusted to achieve this goal, of course. This is for the rack at neutral, needless to say. Also, the left C-hub had to be grinded a little where the hub carrier went on lock ( at least the 0 degrees ones) because they were not molded symmetrically.

Lowering the servo by a mm ( the maximum acceptable amount) does so little for the CG that it just doesn't make any sense to me to take the time to do it...
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Old 07-30-2010, 02:47 PM   #11424
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Quote:
Originally Posted by heretic View Post
MMMh, I agree that a very tight diff is and feels different from a spool, but if you feel a difference between a solid spool and a slipper spool, the latter is likely too loose.

A quick update about my mod, I had the chance to run my TC3 on asphalt with the front inboard toe-out, and it is simply awesome. I highly recommend it, to any tournig car owner, it makes the car really nice. I really can't imagine nor discribe the effect, but the feeling is great. I had left my LCS home, but the track was slower than usual anyways, due to pollen/dust; so I wouldn't have been able to compare lap times with the usual sugared track.

If anyone here wants to test it and give me his feedback... it's only a 20 minute modification.
I can post my setup if anyone's interested, it's surely not perfect but more than decent. A guy at the track who has a bit less skill than me, tried the car and he was on the line after less than a lap. He said thank you several times after that.
I actually built the slipper spool like a diff except replacing the diff balls and rings with the slipper pads. On the XLR-8, I didn't even have to slim the slipper pads because the whole gearbox is wider than the TC3 and simply removed some extra shims. I ran it loose on purpose because I was looking for a different feel that a solid spool. I do like the results. I guess you could say it falls somewhere between a diff and a spool.

On the toe out, I'm thinking of trying it. But I wonder if the difference you feel is actually because of the slight change in Akerman that woud occur due to the change in angle and length of the tie-rods by making that mod?
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Old 07-31-2010, 02:40 AM   #11425
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I understand better. It is strange to want to sacrify front forward traction. At the same time nothing guarantees that the two sides of the slipper spool slip at the same speed/rate... so you're in for a seriously vicious behavior, the way I see it. I guess the criterion is wether you like it or not, of course.

As for the inboard toe-out, my racer mate and I have been theorizing a lot about it, but no one has given a satisfactory description yet because it changes so many parameters at the same time... especially if you run a little front kickup, which I don't for the moment. None of us has gone back to the parralel hinge pins, and yet he is a far better driver than me. Just try it and tell us what you found !

You'll notice that the R+3+2 hinge pin holder has the mounting holes more spaced than the F+0 or F+2 holder. So you'll have to "sacrify" one of these R+3+2 holders by enlarging slightly the hole toward the inside with a 2mm bit, making an oval hole. It does sound like a hackjob but really that's acceptable, and furthermore you're only risking a 50 cents plastic part. I 've done it on a new holder so that I don't cross-thread it with my M3 screw. So you make the holes oval, actually touching the hinge pin in the holder. You can make these hole deeper to the point that the hole is open on the top of the holder, revealing the screw, like DaveW did. When this is done the two holes should be spaced almost accordingly to the chassis holes. You may grind the center bottom of the holder to allow it to flex a little. Now all you have to do is use a X acto to remove a bit of the outer side of the cylinders that go in the bumper. Then remove 0,2 mm of height to these cylinders, so you get an actual 0 degree kickup. It is also important that you do this particular step because you MUST have the bumper "pinched" by the holder in order to have a good rigidity here.

Now use two 12mm M3 countersunk screws. Done ! It is far more difficult to explain than to do. If you want I can post pictures, it's just that I'm lazy taking my front end apart again...
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Old 07-31-2010, 05:52 AM   #11426
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I should be able to figure it out. I have 2 TC3s, an XLR-8 and problably 2 or more TC3s in parts. I've been tinkering with these for over 10 years now including milling down the chassis, experimenting with Losi suspension parts, and I even made a custom fiberglass pan chassis for racing oval. I'll post my findings when I get around to this experiment. I should also point out about the slipper spool that "loose" is a relevant term. The slipper is loose enough that it isn't locked down but it still requires some effort to turn one wheel while you hold the other. The last time out, the car had better on power steering than I've ever experienced with it. I tested on a very hot day with loads of traction coming from the hot asphalt, so that may have affected my experience. I was running 2 degrees of kick-up with 4 degree front uprights for a total of 6 degrees of positive caster. The setup worked very well.
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Old 07-31-2010, 08:18 AM   #11427
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I have always been curious about the use of TC4 and/or losi parts on the tc3 or vice versa. Every time I tried to fit either tc4 or XXXS rear hub carriers, for instance, I have found the measurements of the part different in several ways compared to the original TC3 part. For example the axle height was different between the TC4 and TC4 part, if I remember well. And the offset of the aforementioned wheel axle/hub was different on the Losi part. Did I take the wrong measurement? Maybe. But in doubt, I chose to keep the parts I was more confident with. That won't stop me from fitting TC4 chassis braces asap on my TC3, for obvious reasons. I will also put back the tamiya shocks I removed a few month ago, because these emulsion shocks are a PITA to fill with little rebound, and aren't very smooth. Heck, even the preload collar thread differs from one shock absorber to another, that is super boring. I am too an "old timer" of the TC3, this was my second RC car back in 2000 ( I was 14) and since then I've had 30 more cars, including almost 10 TCs... and yet I'm still using the TC3 ! I bought as many as I could used, with the idea that my hypothetical children will be able to learn to drive with it...haha. Keep us updated on your findings and upload some pictures !
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Old 07-31-2010, 02:08 PM   #11428
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MAN! A lot of activity on this thread! Im glad to see it.

Heretic:

You could also achieve front inboard toe by using the R suspension mount in place of the F suspension mount in the front rear position. I have tried the R in both the front rear/rear front, and the F in the front rear/rear front position. The physics of how front inboard toe works are fairly easy, but in my experience (carpet/foams) its effect on the other front end settings negated its usefulness. I will have to try it out again on the asphalt.

F blocks widen the car when used together, and R blocks narrow the car when used together. The way you did front inboard toe gave you a wider front track. As im sure you know... geometry and handling charateristics are altered with each change.

The lowered servo affects CG, not so much by itself but when combined with everything else as a package. As far as equal steering throw, i dont use Tc3 caster blocks and havent for years. Im not referring to their design, but im referring to the EPA radio adjustments being equal left to right to achieve full steering lock in each direction.

With a Tc3 rack (my preference over the Tc4 swing rack), this places the rack bearings at the racks physical limits regardless of the steering linkage or the caster blocks. With the servo physically mounted chassis level as per instructions with one tooth off towards the centerline of the chassis using the kit servo arm, you will not have full L/R lock AND equal radio EPA settings with a centered rack. This is due to the angle of the link from servo arm to steering rack.

Now while it is true you should never use that much steering throw with a properly setup car, having the EPA throw properly set through correct geometry between servo arm and rack ensures a balanced steering feel when driving. Back then, the lowered servo achieved this AND the lower CG was just some icing on the cupcake.

NOW, the only downfall of the lowered servo or the modded servo arm was steering sensitivity was greatly reduced. While this is hard to relate with the many variables involved in physical and electronic steering adjustments, for me it would equate to a 23-28% change in exponential values.

If my radio was setup with -4 steering expo, lowering the servo, or using the modded servo arm required a + value... as much as +24 at times. That was the only way i could regain the steering sensitivity i was used to, but have equal feel left and right.

I can tear my car apart and take pix of the steering setup and the transmitter adjustments if it would help explain the physical side... but the 'feel' side is only replicated on the track.

----------------------------------------------------------------------------------------

As far as my current Tc3 setup goes, it has evolved some more. I have found HPI springs work VERY well with the car (gold fronts and bright yellow or pink rears). My vertical ballstud mounts are complete and have some tracktime on them. The v2 front and rear towers are working very well. I may opt to add a layer of raw CF sheet to each side of the rear FRP tower... one side at a time.

Also, dont knock an emulsion shock setup with 1mm of rebound for rubber tires. Ask yourself whats more important, a chassis that rolls on its own, or one that is allowed to roll? Just remember to check rideheight and tweak your car out every run... your test results will thank you.
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Old 08-01-2010, 06:26 AM   #11429
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IMHO if you are using logarithmic values ( "+expo") on any RC car, something stinks somewhere. I know that some people do like a very sensitive car around neutral, but still... I't very hard to imagine that the lowering in itself could reduce the sentitivity, especially by that much. But changing the ball stud mount on the servo arm like you did, could produce that because you are changing the lever effect of you servo. As if you had a higher FDR for your servo, if I may put it this way.

I understand what you say about the rack being on lock before the hub spindle/hub carrier hits the C block. Out of the box it is not the case on the left side though, so I figured I would mention it.

What you point out as a problem is not really one for me : the fact that the travels are like R62 vs L95 does very little for the symmetry of the steering feeling. The obvious reason for this, is that you TX recalculates your travel as 100% for each side at the very same time you adjust travel, so to me that is a false problem.


What C-hubs do you use ? I use aluminium Corally RDX ones, really close if not absolutely identical to AE ones. This way i break A-arms instead of Chubs, which are difficult to manage as spare parts because they are asymmetrical left and right and can have different values. So when you break one th'ere is a fair chance you don't have a spare for it. On the other hand, front arms are front arms, period. Plus its way faster to replace when broken.


sorry for the approximative English, if you need a reformulation just ask.
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Old 08-02-2010, 11:33 AM   #11430
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Quote:
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I't very hard to imagine that the lowering in itself could reduce the sentitivity, especially by that much. But changing the ball stud mount on the servo arm like you did, could produce that because you are changing the lever effect of you servo.
The average Tc3/4 chassis thickness is 0.100". If the servo is lowered in the chassis so that its bottom is level with the bottom of the chassis, and you use a non modified Tc3/4 steering servo arm, then your steering arm ballstud is lowered by the same thickness of the chassis.

Using a non modified chassis and mounting the servo with a servo arm modified with a hole 0.100" lower than the stock arm hole, gives you the same geometrical fix WITHOUT the minute CG change and resultant chassis flex of the modded chassis.

Either way, you have a 0.100" drop of the servo arm ballstud.

Quote:
Originally Posted by heretic View Post
What you point out as a problem is not really one for me : the fact that the travels are like R62 vs L95 does very little for the symmetry of the steering feeling. The obvious reason for this, is that you TX recalculates your travel as 100% for each side at the very same time you adjust travel, so to me that is a false problem.
Imagine you have 100 lines left and 100 lines right. You have to fit those lines within a 3mm throw left and a 5mm throw right to reach the same endpoints (on the rack... im not even discussing caster blocks at this point).

For example, 25 lines:

Left: lllllllllllllllllllllllll
Right: l l l l l l l l l l l l l l l l l l l l l l l l l

One direction would feel more aggressive than the other (same information packed in a varied range of physical travel when compared), making your steering feel unbalanced. You can kind of relate this as mechanical 'exponential' though varied mechanical leverage and range. The feel wouldnt be linear left to right. TX expo is a different matter.

Now, im sure this isnt something everyone would notice... especially if they didnt know what they were looking for. Trust me though, it makes a difference when your looking to trim 10th's off your laptimes.

Something i was told years ago is something i live by for all sizes/classes of racing... build the car geometrically and mechanically sound, and the rest will fall into place. Racing is about making the best out of every aspect of your car, so you can wheel it to the best of your ability. Finding and fixing even the smallest of issues, can result in huge changes when combined.


Quote:
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What C-hubs do you use ? I use aluminium Corally RDX ones, really close if not absolutely identical to AE ones. This way i break A-arms instead of Chubs, which are difficult to manage as spare parts because they are asymmetrical left and right and can have different values. So when you break one th'ere is a fair chance you don't have a spare for it. On the other hand, front arms are front arms, period. Plus its way faster to replace when broken.
My caster blocks are Losi off of the XS platforms. I have yet to put a Losi or AE car together where i didnt have to adjust their fit and finish to my liking. Thats ok though... its one reason i love this hobby as i do.

As far as spares go, i cant remember the last time i broke an arm or a caster block, but if i had to choose i would rather replace an arm. Caster block symmetry isnt an issue for me... rarely will i use full lock to lock steering and hit a caster blocks limits during a race.

The last Tc4 part i had to replace from breakage was a rear shock tower... from being hacked and flying into a wall... and a Tc4 steering rack... which i no longer use for this very reason. I replace arms from wear and slop, and steering blocks because the threads strip out from frequent rebuilds.
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