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Old 11-05-2016, 04:54 PM   #1186
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At 25mm, that would put the xv-01 at the maximum height. No sag would make for a very unstable ride especially if there are pot holes rather than bumps. I agree 20mm is probably pretty good.

For me 12mm is a little too high for street driving. I found that 18mm+ the car flips really easily. Does this happen at all in your rally racing? Or is there enough give in traction to avoid flipping the car?

Do the big bore shocks rub against the front gear cover?

Are the other cars capable of getting 25mm of ride height? Seems like a lot for the Touring Car chassis.

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Ehm :-). The recommendation for our races is 25-28, 20 is the lowest acceptable ride height (track is mixture of gravel, dirt, grass). ;-)

Personally I think 25 is little too high, so I'm staying at 20, and it seems to work OK so far.
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Old 11-06-2016, 12:01 PM   #1187
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For 25mm, I would have to modify already modified chassis... With my car (or even the stock one), you are absolutely right, the car would be pushed to its limit at 25mm, which is no good.

Modifying the chassis to achieve reasonable ride height is the first step in converting any car to true rally car. And that is also the reason why only old touring car chassis (like TA-02) are being used besides XV-01. They are not so specialized as the modern ones, so achieving 20mm is relatively easy with them.

At 20mm, it is certainly not a high-speed tarmac racer. It flips at hard turns at full speed, especially without the front sway bar. But that's not the point of rally racer. It very rarely goes really fast. If you manage to keep Center of Gravity low enough, the car well balanced, and suspension working, it hardly flips during the race. I usually flip it on grass only, when I push the throttle too much exiting the corner. Otherwise it is pretty stable.

12mm BB shocks (Team Associated, Team Durango, Losi, etc.) are absolutely no problem. They don't even touch the cover.

14mm Gmade BB shocks (19mm spring) are a bit of problem in terms of mounting in the front, but manageable. You need to use the inner mounting position on the a-arm, as in the outer, wheels are hitting the shock at full turn (no problem with stock steering, though). Even then, 6mm hex is required, or wheels with at least +3mm offset, or both (for larger tires). In the inner position, it is very lightly touching the gear cover and body post, but it works.

So mounting is not really the problem with Gmade's. I have to reasons why I'm switching them to smaller TAs:
1) Springs - Good luck finding good selection of 19mm springs. Gmade will sell you exactly 3 different rates, which are all hard (for XV-01). Then you can get Pro-line PowerStroke Front springs, but those too are too hard except maybe one, which is good for XV front. Nothing really for the back of the car. So you need to get a custom made one.
2) Diaphragms. This is a small rubber thing in the shock cap (for XD shock), and I already blew 2 of the 4 I have. Not sure why, most likely because I'm running the shock without bump stops (it has a ridiculously short travel with them), and the rod travelling all to way up to the cap is breaking them. Switching to Aeration caps, and building the shock as low pressure helps (although it takes time to do it right).

I don't mind the problem with Diaphragms, as it can be solved. But the lack of good springs is a showstopper.
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Old 11-06-2016, 06:51 PM   #1188
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Default Heat Dissipation

Today I drove my car at the big open parking lot which is covered in smooth black tarmac.

Todays setup BMW M3 GT Coupe body. Ride 24mm USGT spec tires on 5 spoke Tamiya rims.. 400 CST oil with 3 hole pistons in all four TRF dampers. Whites (ultra hard springs) in the front and blues (hard) in the rear. 8mm ride height F/R. Hard front sway bar, nothing in the rear. Hobby Wing ESC and 13.5T motor set at 15degree timing, 24degree turbo - 0.5s delay starting @ 12000RPM, 5000mah 2s Lipo 50C. 32/72T gearing. Locked slipper. 150K CST oil in the front diff, 300CST in the rear.

TC suspension performed amazing! The car was dialed and drifted around corners like a GT car is suppose to. After 15-20 minutes of driving balls out my ESC/Motor was running hot and started cutting out because of thermal shutoff.

I needs me a motor heatsink, or to put the fan back up front.

Coming in hot!
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Old 11-07-2016, 10:37 PM   #1189
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Quote:
Originally Posted by haplm View Post
Modifying the chassis to achieve reasonable ride height is the first step in converting any car to true rally car. And that is also the reason why only old touring car chassis (like TA-02) are being used besides XV-01. They are not so specialized as the modern ones, so achieving 20mm is relatively easy with them.
Only TA02 ad XV-01? I don't know, but I see mostly Xrays T2-T3, which count as modern TC cars, altough they are several years old Achieving 25-30mm with TC suspension is easy too, although you need some more dremeling in front area, on the other hand, longer suspension arms and swing shafts are better for higher car. Reason why some people use TA02 is their simplicity and that it's easier to make custom chassis (no need to measure and buy custom belts) and fact that their wheels doent jam against suspension arm when rock get inside
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Old 11-08-2016, 12:37 AM   #1190
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Only TA02 ad XV-01? I don't know, but I see mostly Xrays T2-T3, which count as modern TC cars, altough they are several years old Achieving 25-30mm with TC suspension is easy too, although you need some more dremeling in front area, on the other hand, longer suspension arms and swing shafts are better for higher car. Reason why some people use TA02 is their simplicity and that it's easier to make custom chassis (no need to measure and buy custom belts) and fact that their wheels doent jam against suspension arm when rock get inside
One time I forget to mention X-Ray, and it immediately comes back to me :-). Yes, of course T2 and T3 too ;-).
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Old 11-08-2016, 05:21 AM   #1191
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Hey guys, here's an update on my rebuild. I am almost ready to go, just waiting on a set of front hubs, which are on backorder

The rebuld went very smoothly, and the car is in great shape. I used a set of black TRF shocks and black springs from my TB01 to get the blacked out look, other than the blue suspension mounts of course.

I'm running an old LRP 13.5 BL with a TBLE-02S speed controller. It's geared pretty conservatively, so I hope I don't have any issues with the ESC handling the motor.

[IMG][/IMG]
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Old 11-08-2016, 07:12 AM   #1192
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Looking good! I see you moved the ESC to the front of the radio box. IMO Tamiya really had to try to offset frontal weight by forcing those that could put the heavy electronics in the back. But it's such a stretch.

The blacked out look is nice. I love seeing other peoples chassis!

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Originally Posted by ErikO View Post
Hey guys, here's an update on my rebuild. I am almost ready to go, just waiting on a set of front hubs, which are on backorder

The rebuld went very smoothly, and the car is in great shape. I used a set of black TRF shocks and black springs from my TB01 to get the blacked out look, other than the blue suspension mounts of course.

I'm running an old LRP 13.5 BL with a TBLE-02S speed controller. It's geared pretty conservatively, so I hope I don't have any issues with the ESC handling the motor.

[IMG][/IMG]
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Old 11-08-2016, 07:18 AM   #1193
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Back in the days of my AE rc10, I found the Teflon coated dampers were great and their selection of springs was awesome. I had like 10 pairs in all different colors and stiffnesses. My favorite were the soft green ones. I am not sure if they fit on road style dampers though. They may have been a larger diameter. RPM also made some good stuff too, but mainly for off-road.

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Originally Posted by haplm View Post
12mm BB shocks (Team Associated, Team Durango, Losi, etc.) are absolutely no problem. They don't even touch the cover.

So mounting is not really the problem with Gmade's. I have to reasons why I'm switching them to smaller TAs:
1) Springs - Good luck finding good selection of 19mm springs. Gmade will sell you exactly 3 different rates, which are all hard (for XV-01). Then you can get Pro-line PowerStroke Front springs, but those too are too hard except maybe one, which is good for XV front. Nothing really for the back of the car. So you need to get a custom made one.
... But the lack of good springs is a showstopper.
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Old 11-08-2016, 09:15 AM   #1194
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Quote:
Originally Posted by 4roller View Post
Looking good! I see you moved the ESC to the front of the radio box. IMO Tamiya really had to try to offset frontal weight by forcing those that could put the heavy electronics in the back. But it's such a stretch.

The blacked out look is nice. I love seeing other peoples chassis!
Thanks for the kind words!

It seemed like a logical location given how long the motor wires already have to be, and that I'm already using my longest sensor wire!

The ESC and receiver weight so little as it is (especially the Tamiya ESC), I'm not sure how much of a weight difference it would have made. The biggest improvement in front/rear balance would probably be a really heavy high mAh battery!
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Old 11-08-2016, 09:53 AM   #1195
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Quote:
Originally Posted by 4roller View Post
Back in the days of my AE rc10, I found the Teflon coated dampers were great and their selection of springs was awesome. I had like 10 pairs in all different colors and stiffnesses. My favorite were the soft green ones. I am not sure if they fit on road style dampers though. They may have been a larger diameter. RPM also made some good stuff too, but mainly for off-road.
Selection of springs for these shocks is simply superb. Somebody even took time to compile the list. It is slightly outdated, but you can actually find even more springs (not less) today.

What you need for 75mm shocks are 45mm front springs. Team Durango does great set of soft ones, and then if you need something a bit harder, TA soft and medium set continues. Avid also does some good sets.

Next thing I've got are tapered pistons with 3 and 4 holes. They allow the shock rebound faster than compress (or vice versa, if you want), which is a nice feature too.

I'm using selection of Hudy shock oils. They start at 100 cSt, and I have them all the way up to 900 in 100 increments. Since it is cold outside, I'm driving over stuff at home, recording it on 240p camera to see what's happening with different number of holes in pistons, springs and oil. Not much fun, but tells a lot.
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Old 11-08-2016, 01:02 PM   #1196
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Quote:
Originally Posted by ErikO View Post
Thanks for the kind words!

It seemed like a logical location given how long the motor wires already have to be, and that I'm already using my longest sensor wire!

The ESC and receiver weight so little as it is (especially the Tamiya ESC), I'm not sure how much of a weight difference it would have made. The biggest improvement in front/rear balance would probably be a really heavy high mAh battery!
You could always do a rear-motor conversion like I did. That will make the motor wires and sensor wires much shorter. Lots of work though.
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Old 11-08-2016, 10:54 PM   #1197
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Actually a really heavy Mah battery would offset the left right balance too much.

I run a 5000mah 2s hard pack. And the car definitely biases towards the left side of the car. I rearranged whole electronics to try of offset that weight, putting the ESC in the rear, and then the heavy 12 gauge wires on my ESC to the very right edge of my car. I even went so far as to make some balancing pins. To balance my cars left right weight, I would need to put something like the weight of a 18650 battery on the electrics side. Or, get a lighter battery.

In any case, I've found you just need to change your preloads in the dampers to handle the weight imbalances.

But for rear traction, a rear mount motor would be good, except then, your front be too light and the car would understand like crazy. Thicker rear sway bar!


Quote:
Originally Posted by ErikO View Post
Thanks for the kind words!

It seemed like a logical location given how long the motor wires already have to be, and that I'm already using my longest sensor wire!

The ESC and receiver weight so little as it is (especially the Tamiya ESC), I'm not sure how much of a weight difference it would have made. The biggest improvement in front/rear balance would probably be a really heavy high mAh battery!
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Old 11-08-2016, 11:00 PM   #1198
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I am 2gearboxes, a chassis and a full set of tie rods away from building a second xv-01.

Almost everything I have as a spare. I'd definitely play with a rear mount motor car if it made econimical sense to buy those listed parts.


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You could always do a rear-motor conversion like I did. That will make the motor wires and sensor wires much shorter. Lots of work though.
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Old 11-08-2016, 11:52 PM   #1199
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Default xv-01 TC sway bars

So I got a TRF418 sway bar kit.

This kit comes with 3 bars for the front and 3 for the rear. The front bars are thicker by 0.1 and 0.2mm than those of the standard xv-01 kit and the rear are 0.1 thinner.

To mount them to the xv-01TC I needed to trim 7mm off the rear bars so that they would not interfere with the rear fender mount. I could have used the original fronts, but opted for the second thickest bar on the front and the thinnest bar on the rear using the TRF418 kit.



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Old 11-09-2016, 06:23 AM   #1200
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Considering the primary purpose of my XV-01 is to mess around outside with friends and have a laugh, I'm fine with less than perfect weight balance haha.

I have my EXO6 to go academic on!
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