In ETS 21.5t spec, the car has a total weight now of 1215g with my 81g heavy bodyshell. That is 85g below the weight limit of 1300g. The car without bodyshell is only 1136g. That should be plenty of margin to play with weight distribution, and to have the CG as low as possible.

Looking forward to use this at the next ETS. I’ll need to order more of the Hudy tungsten weights for next ETS.

Here is what I used to get the car down to this weight:

  • #301020 X4'24 Alu Flex Chassis 1.5mm - Swiss 7075 T6 (83g instead of 108g)
  • #913300 Hex Screw 110° for 301020 X4 Chassis – Hudy Spring Steel (necessary for 1.5mm Chassis)
  • LRP UltraLCG StockSpec 135C/65C 5100mAh 7.6V Lipo (248g total weight nominal, mine is 245g)
  • OfficinaRC Titan UFS Screws (saves about 10g total)
  • Titanium Turnbuckles (saves about 1.6g total)
  • 2x #990101 Hudy Titan Pivot Ball D=4.9 / S=5 / 3mm Hex (2) (saves about 1.2g total)
  • 2x #990008 HUDY Titanium Ball Stud D=4.9 / L=8 / S=3.5 / 2mm Hex (2) (saves about 1.3g total)
  • 1x #990006+#990004 HUDY Titanium Ball Studs (saves about 0.5g total)
Now it’s time to order some Hudy Tungsten weights, to have the ballast weight placed neatly as low as possible on the chassisplate, to come back to the ETS minimum weight:
  • #293081 HUDY Pure Tungsten Weight 5g (9.5x11x2.5mm)
  • #293082 HUDY Pure Tungsten Weight 10g (19x11x2.5mm)
  • #293083 HUDY Pure Tungsten Weight 15g (19x16.5x2.5mm)


There is quite some interest in my X4’24 as I used it in Wiener Neustadt.

The car was amazing throughout all the test sessions before the race on various tracks, and also at the ETS it was close to perfect from the start. We don’t need to make many adjustments with this setup.

So here are the specs of my car:
Xray X4'24 carpet spec XRAY: Not much to say about this. Certainly one of the best touringcars on the market in terms of performance quality and durability. Perfect for stock class racing.

My setup sheet is online here:

Here are the optional and electronic components that I used:
  • Xray Rubber Bumper 3D 301233: This one gives more durability and changes the airflow under the car, as air can go through it. When I was starting to use it, I felt it was taking away a little bit of consistency, due to the increased front grip. If you are crashing on a more regular level, I suggest to use the hard foam bumper 301232, this one makes your car extremely durable.

  • 302640-T X4 Adjust. Camber Screw 14mm M4 L/R - Titanium (2)
    Reduces the weight high up in the car.

  • 301020 X4'24 ALU FLEX CHASSIS 1.5mm - SWISS 7075 T6
    This one is a slightly underrated upgrade. Sure, the it doesn’t make you like 0.1s faster per lap. We are talking rather about a few tenths on a 5 min run, but nevertheless this adds up. Note, you will also need the 913300 Hex Screw 110° for 301020 X4 Chassis -HUDY Spring Steel (33) to make it work. So this is not exactly a cheap upgrade.

  • Hudy titanium Pivot ball and ball studs 990101, 990004 990006, 990008, 990010, 990102 HUDY: These reduce the weight, most of this are placed rather high in the car. Even if they get replaced by additional weight on the chassis plate, this reduces the CG. Also these parts seem to have slightly less play than the original steel parts.

  • 309852 X4 Brass weight Nickel coated for motormount: These are placed in the middle of the car, low down in the motor mount. They don’t need space for anything else, so a perfect place to add some weight. However, they are only 16g in total.

  • Hudy Pure tungsten weights 293081, 293082, 293083: after all this weight reduction, there is really a lot of ballast weight needed. I recently upgradet to hudy tungsten weights. One 15g weight in each corner, and the rest used to get a perfect weight balance (left to right identical, front 10g heavier than rear)

  • 308029 XLP/UPL Alu Progressive shock system with 308028 Composite PSS 2-Holes 0.8mm Piston (4)
    This gives more rotation on high grip surfaces. When you use it the first time, it feels a bit strange on power, but at least for me it is quicker every single time on ETS carpet. A nice side effect is, you can drive harder over the curbs with the inside wheels without flipping the car over.

  • OFC-X424xUFSFKK Officina RC Monaco RC
    [OFC-X4-SPGEAR] OfficinaRC Titanium Special Spur Gear Screw for Xray X4
    [OFC-X4-UPP] OfficinaRC Titanium Upperdeck Screw for Xray X4 (2)
    [OFC-X4-SPGEAR] OfficinaRC Titanium Special Spur Gear Screw for Xray X4
    [OFC-SS-39KIT] OfficinaRC Alu Smart Shim 3x9 Kit - (60)
    Titanium screws: As the car is underweight on carpet anyways, I use only the upper screws in titanium. For Outdoor I will also use the countersunk screws in the chassis.

  • NOSRAM HV ULTRA LCG STOCK SPEC GRAPHENE-4.1 5100MAH HARDCASE - 7.6V LIPO - 135C/65C Nosram: due to availability I have used the equivalent from sister company LRP, the G4.1 5100 HV ULTRA LCG STOCK SPEC AKKU #432277
    The performance of this battery is amazing. After cycling well below 2mOhms resistance per cell, with a rather flat discharge curve, so there is still good voltage at the end of a stock run. And most important for high grip conditions: this battery is only 20mm high and weights only 245g. This really gives the edge in stock racing. No matter if black or blue 😊

  • Zooracing Wolverine bodyshell RC-KleinKram Stefan Klein: No it’s not a Volvo 😊 For me this bodyshell is currently fixed for stock class. I don’t even bring other bodyshells to the track. At ETS we need to run the 0.7mm version, which is good for durability, and I run my paintjob by Björn Keller, who reproduced a TC version of the 2020 Williams F1 design.

  • ORCA 21.5T ETS combo TONISPORT: This one is fixed for ETS. We run with RPM limiter, which gives very similar topspeeds for all cars. I had my issues with the high low end torque and low high end power in the 13.5t class, but with the 21.5t motor and longer gear ration, that feels really good, it reminds me of the 17t brushed racing I did more than 20 years ago, I was comfortable with this from the beginning.

  • Futabe T10PX radio: Minicars Hobby Distribution AB: I recently switched my radio from Sanwa to Futaba. I really like the better brake feeling. Apart from that, racing it feels quite the same. The touch display is a world ahead of the sanwa, but that is rather nice to have and does not change a thing for racing.

  • Futaba CT501 Servo: this servo has amazing power and precision, and is lightweight at the same time. With the digital ultra response mode, I feel this gives me an advantage in precision and reaction. The servo has a plastic casing for lightweight. You can also use the alu version CT702 with alu casing and even more torque. Note, you really need to use a capacitor on the receiver when you want to run these servos from the BEC to avoid radio glitches. Even with a 6A BEC.

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