Last sunday, I raced my (quite heavily! 😀) modified HNR H9804 FoxHound at the Czech National RC Rally Championship event, RC Rally Zálesí in Humpolec. The car handled beautifully, allowing me to take 7th place overall in a highly competitive field.

To share some insight, here is the breakdown of the EmbieRacing (ER) and other custom modifications that made this result possible:

Chassis & Layout

• Lower Chassis:
  • ER PROTOTYPE glass-fibre shortened chassis. This allowed me to straighten the rear driveshafts compared to the original setup, which is too long and features forward-facing rear suspension arms.
• Central Driveshaft:
  • ER PROTOTYPE glass-fibre shortened rear central driveshaft. Originally just a test piece, its performance has been excellent, resulting in significantly less wear on the outdrives.
• Chassis Brace:
  • ER PROTOTYPE 3D-printed rear chassis brace.

Suspension Modification

• Front:
  • Front suspension arms from the ER HNR KIT – UPGRADE SUSPENSION ARMS SET.
• Rear:
  • ER PROTOTYPE 3D-printed rear suspension arms designed to fit the shortened chassis. The dampers are now front-mounted. Fitting them this way was quite a challenge due to limited space—requiring modifications to the original cover and battery holder—but the handling improvement is definitely worth it.
• Anti-Roll Bar:
  • ER PROTOTYPE 3D-printed anti-roll bar holder.

Steering & Drivetrain

• Steering Hardware:
  • ER HNR KIT – STEERING HARDWARE (part of the ER HNR KIT – FULL) with a 16 mm wide steering arm, paired with a 3 mm spacer at the steering knuckles to reduce bump steer.
• Top Deck:
  • Stiffening Top Deck (included in the steering hardware set).
• Driveshafts:
  • YeahRacing (XR-T4-027) driveshafts paired with Xray 3.5 mm plastic drive shaft caps (XR-305241). Using plastic caps drastically reduces outdrive wear.
    • Tip: While you can use 3.0 mm caps, I used what I had at home. This required widening the outdrive slots to 3.5 mm, but the 3.5 mm caps have better availability and last longer.

Dampers & Shocks

• Shock Towers:
  • ER HNR KIT – ADJUSTABLE SHOCK TOWERS.
• Dampers:
  • Xtra Speed Aluminum Big Bore Damper Combo Set (XS-TA29208GD), using 75 mm at the front and 90 mm at the rear.
• Top Damper Joints:
  • Modified using this Printables 3D model ( https://www.printables.com/model/1647996-rc-car-shock-damper-top-joint). Crucial step: Double-check that everything moves smoothly here.
• Inner Shock Spacers: Custom 3D-printed spacers.
  • The original spacer is about 2.4 mm high, which over-compresses the sealing X-rings and causes the piston to bind. I replaced them with 3D-printed versions (marked in red in the picture) lowered to 1.4 mm, making the dampers very smooth.

• Springs:
  • Blue springs on both axles from the Tamiya Big Bore Damper Spring Set (Aeration Type):
    • Front set (4WD): 54506
    • Rear set: 54508
• Oil: 200 cSt front / 350 cSt rear.

Pictures will be added later!

ER HNR KIT – FULL includes:
– ER HNR KIT – STEERING HARDWARE
– ER HNR KIT – STEERING ACCESSORIES
– ER HNR KIT – UPGRADE SUSPENSION ARMS SET
– ER HNR KIT – ADJUSTABLE SHOCK TOWERS
– ER HNR KIT – FRONT BUMPER ANGLER

All included parts described more detailed in separate posts bellow.

https://www.ebay.com/itm/267708514076

Kit to turn your HNR H9804 into a true RC Rally weapon!

• extreme steering angle for maximum cornering performance
• integrated steering angle limiter for easier setup
• high rigidity thanks to a carbon two-piece top deck
• designed with servosaver compatibility

For best performance, I recommend using driveshafts with a higher working angle to handle the increased steering range.

Optional upgrade:

Modified suspension arm set UPGRADE SUSPENSION ARMS SET and STEERING ACCESSORIES, available separately.

– front + rear
– 4x screw 8mm
– 4x M3 nut

Fits most dampers used for RC rally – from original ones up to big bore buggy dampers.

Modified suspension arms set for HNR H9804

• for width ca 195 mm (stock H9804 ca 180 mm width)
• for normal wheelbase ca 256 mm (stock H9804 ca 5 mm longer – not fitting usual RC rally 1:10 bodies)
• modified for higher clearance without cutting
• made full without holes to improve strength + cleaning
• PA12 SLS – despite the „3D printed look“ this part is very durable

Longer driveshafts needed at front (for example YeahRacing XR-T4-027), rear better longer as well, but temporarily can be used with stock ones + ER printed spacer (free to download at prinatbles.com).

All 3D printed parts of EmbieRacing Ralcon for Xray T3 are now available for free download at Printables.com!

→ EmbieRacing Ralcon – all parts on Printables

What you can get from Printables (free download):

This means you can print all plastic parts yourself and build your own RC rally weapon. Carbon parts files are included as well – those are primarily for testing purposes, as printed versions of structural carbon parts will be significantly weaker. For real use, carbon parts need to be CNC machined.

All 3D printed parts – diff cases, covers, steering block extensions, battery holder parts, servo area cover, and more.

What you will still need from me:

– CNC machined carbon parts (lower chassis, top deck, carbon steering arm, shock towers, battery holder carbon parts)

– Timing belts (front + rear)

– Accessories set (screws, nuts, ball bearings for belt tensioner, turnbuckles, shimms)

What you need to source yourself:

– Xray T3 / T3’10 / T3’11 / T3’12 as a donor chassis (or compatible copy – not tested)

Full list of what’s needed is described in the original EmbieRacing Ralcon post under the „INCLUDED” section.

If you want to go the DIY route and just need the carbon and accessory parts from me, feel free to get in touch via the Contact page.

Let’s build your RC rally weapon! 🔧

Recently I’ve been asked what dampers I use for RC rally. I discovered these some time ago under brand Koswork but later realised, that those are sold under multiple brands. I tried to order same looking set but branded Xtra Speed with a bit lower price and received exactly the same thing. Than I realised that also brand EXO Design sells very similar looking set of dampers – these I haven’t tried, but I believe those are the same too.

Recap:

XS-TA29208GD – Xtra Speed Aluminum 75mm & 90mm Big Bore Damper Combo Set For 1/10 RC Buggy

• these I use actively
• cheapest, sometimes unavailable
• best set – contains more parts (upper and lower joints that are not included in bellow mentioned)

KOS04901GD – Koswork Aluminum 12mm Gold F&R Big Bore Buggy Shock Set For 1/10 RC Buggy

• these I’ve had in the same time with above mentioned in hand, it’s the same product
• bit higher price, better availability

EXO-005SGD – EXO Design Universal 12mm Big Bore Shocks Set For 1/10 RC Buggy

• looks same as both above mentioned, never had in ma hand
• seems it contains all the parts that Xtra Speed ones do
• highest price

Springs:

I combine these with spring set from Tamiya:

54506 – Tamiya Big Bore Damper Spring Set – Aeration Type – Front (4WD)

54508 – Tamiya Big Bore Damper Spring Set – Aeration Type – Rear

How to order:

Just place the product number in the search form at rcmart.com – whis way I ordered. Probably you’ll be able to order at different shops.

How they work:

I’ve been racing those for ca 8 rally races now. Till now I havent noticed any oil leak. As everything seems precise and tight fitting, I use for those low oil viscosities 100-200 cst. In general I find those very good dampers.

3D printed top joint

At printables.com by searching „RC CAR SHOCK DAMPER TOP JOINT“ you’ll find Top joint with implemented hex nut for Koswork/ Exo Design/ Xtra Speed that I find best to use with these dampers. Top joint from the package will work for you as well anyway.

EmbieRacing Ralcon for Xray T3 is a RC rally conversion kit for converting your (bit old but still good!) onroad Xray into ultimate RC rally machine!

With this kit you don’t need to create any dust cover, it’s just part of it! Differential cases are completely closed. No need for any rubber bands or duct tape, top of the cover is just clicked on the rest. To release it just use rear „wings“ to unclick.

On the contrary to sealed diffcases – whole steering including servo, where most dust is usually coming inside your dust cover, is completely outside the covered area, so there is no space for dirt to get in. 

Top and frontward mounted servo is the best solution for steering geometry and as well for putting most weight to the front axis. It’s just up to you (and your drive shaft limits :-D) if and how much you will cut the original steering blocks, steering geometry will work well with any angle. Frontward mounted motor and battery are helping this effect even more. All the heavy components (battery, servo, motor) are placed as close as possible together helping to achieve awesome steering reaction and changes of directions. 

Battery holder is included in the kit. Shorty battery is the best working in this kit and only one what will fit cause we don’t do any compromise.

Adjustable shock towers included as well, they will work with any dampers used for rally (pushed damper hole to hole min 48 mm to 70 mm) and can help you to set up the height or change the damper in a while.

Lower carbon chassis, extremely narrow under the diffs to allow all the dirt fall from suspension with rear downstops remaining, front ones cutted away as you are used to from other EmbieRacing rebuild kits. Same with anti roll bars – front one not used, space for rear one remaining.

Accessories like screws, nuts, ball bearings for belt pulley included in the kit. As all the parts are manually collected, please allow some screw missing, but of course we will try to avoid this. For Xray T3 from year 2010 you will also need four ball joints instead of roll-center excenters.

For which onroad chassis is this kit? It’s for Xray T3 (sometimes marked T3’10), T3’11 and T3’12.

Materials used – carbon fiber, plastic (3D printed)

Availability – September 2025

Starting price 150 € whole kit (without OEM T3 parts)

Assembly sequence and screws to be used

Video manual how to assemble on YouTube. It’s not the best manual you ever seen, but it should be clear anyway. Just skip the boring parts with rigth arrow 😁.

Part 1 

Part 2

INFO LOG (updated 27.8.2025):

TESTED SERVOS:

Savöx SC 1251MG

Rib between screws needs to be removed.

Other servo may need some modification or to be positioned with shimms (moved upwards).

SERVOSAVER:

Xray T3 2010 does not have included servosaver (372503).

INCLUDED:

Have you thaught about having your Tamiya XV01 as a rear wheel drive? But you don’t want to buy special kit for this purpose? All in One EmbieRacing kit for Tamiya XV01 is exactly for you!

What means All in One kit? It means you are able to use this kit in all configurations you can think about:

• Standard front motor – 4WD
  Standard front motor – FWD
  Rear motor facing rearwards – 4WD
  Rear motor facing rearwards – RWD
  Rear motor facing forward – RWD

Multiple servo position options, multiple battery position and holders (sold separately) options, in front motor configurations possible to use standard ER mudguard holders. Some of options/holders can be used only in some configuration.

With this kit, you can enjoy all the features of EmbieRacing XV01 Standard kit, but many more too!

Widely used especially (but not only) by RC Rally drivers. With top servo position it provides smoother steering without stucking rocks, wider steering angle possibility and better steering geometry. Touring car drivers can use original steering rack with original servo position – all of that in one kit. Kit provides better weight distribution, you can choose from different battery positions with additional battery holder (sold separately). Lower chassis is cutted under arms for better clearance, but downstops are still ready to use (for even higher clearance you can grind the edges of chassis). This kit is completely plug and play, no additional upgrades needed!

BATTERY POSITION OPTIONS:

• holder sold separately, some of options not possible to use in exact configurations
• REAR TRANSVERSE POSITION: Weight of battery at the end of the chassis. Battery holder can be chosen for normal sized or shorty LiPo.
• LONGITUDINAL ON AXIS POSITION: Battery at the centre line of chassis. Fixing holes for both standard size and shorty LiPo. When using standard size battery, only top mounted servo position can be used. Timing belt can collide with battery connetor on some cases.
• REAR LONGITUDINAL ECCENTRIC – Similar to previous, but battery holder is eccentric, so top deck does not interfere with battery connectors. Both standard size and shorty LiPo can be used. This one is not recommended for ALLinONE kit, because of different Top Deck in comparison with Standard kit.

OTHER INFO

SERVO POSITION OPTIONS:

• some of the options not possible to use in exact configurations
• TOP SERVO POSITION: servo mounted at the top deck with servo arm and steering arms extension. Used for RC rallying. This options gives you possibility to use maximum steering angle. Ackerman angle (steering angle of outer wheel in corner) is increased.
• ORIGINAL SERVO POSITION: position of servo as „from the box“. Extendors of servo and steering arms not used. Recommended to raise original steering rack with washers. Collision between top deck and servo arm may occur, depends on steering arm length.
• MIDDLE SERVO POSITION: similar to original servo position, but servo is way closer to chassis centre line, giving you better weight balance. Extendors of servo and steering arms not used. Recommended to raise original steering rack with washers.

WHAT IS INCLUDED:
Lower main chassis
Upper top deck – 2 pieces
Servo arm extension for top mounted servo option
Steering arms extensions for top mounted servo option

WHAT IS SOLD SEPARATELY/NOT INCLUDED:
Shock towers (check also adjustable shock towers to fit all rally dampers)
Battery holder
Mudguard holders
Electronics
Screws etc

WANT TO BUY THIS? Follow the link or send me a message!

Material: High quality carbon fibre composite, 2,5 mm thick

1 2 3 ►

 Let me quickly show you first prototype of
Tamiya XV01 ALL IN ONE Kit by EmbieRacing! 🧐👍👇

ℹ️More information:
Months ago I had the idea to create XV01 RWD kit.
Few days back I finally started working on this project
and after some work I realised, that with certain
modifications I can manage to create one kit with all
these features:
– 4WD XV01 with front motor (standard)
– 4WD XV01 with rear motor
– RWD XV01 with rear motor position facing rearwards
– RWD XV01 with rear motor position facing frontwards
– FWD XV01 with front motor (yes, this is standard XV
01, but just to complete the list 🤣).
All of this I was able to achieve by creating doubled
diferential case holes on lower chassis and top deck
mounted from two parts.

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