The new 2024 kit has seen some noticable changes on the track, altough you may not notice them on the first sight in the pits. Therefore, I decided to make a few more posts about the XB4, the same way I did with the XB2, to introduce you to some of the key improvements and option parts I use on my car.
Starting from the front of the car, there is a new shocktower with more shock and camber link positions. We also have new mixture steering and caster blocks, altough for high-class carpet racing I recommend the optional aluminium steering blocks and hubs set with 7o of caster. These parts are the same ones you could get with previous models, but the graphite steering extensions saw a big improvement.
With the set you get a 1dot option, which is the most aggressive, but you can get a 2dot or 3dot options, which with each step get the outer wheel turn less and therefore making the car easier to drive and carry more corner speed. The 1dot is best suitable for tight tracks, whereas the 3dot is best for high grip and flowy tracks. The 2dot is right between these two.
The graphite mixture front arms is a must for me on carpet, which is valid for the ECS drive shafts as well. These ones have much less vibration while cornering and improve the stability of the car. If you drive on very high grip, I can also recommend the 2mm sway bar for the front.
You can find these option parts under the part numbers:
#360900 - Alu Steering Blocks & 7o C-Hubs (set)
#362270 and #362275 - 2dot and 3dot graphite steering extensions (sets of 2)
#365202 2x - ECS front drive shafts 2x (set)
#362112-G 2x - Front Graphite mixture arms
#362480 - 2mm sway bar for high grip
Going to the back of the car, we can again see a difference in the materials used on the arms and hubs, with featuring the new "low" hub in the kit. Altough while racing on high grip, I would usually be looking for a stable car, for which I can recommend the rear hub in the Alu option.
On carpet I have personally liked the rear wider pivot holders (C and D blocks), which for me provide much more stability for the car. This needs to be used with the shorter arms, which are the same from the 2WD car then. In case you choose to run either of these configurations, I can again only recommend the Graphite mixture rear arms for high grip. For dirt and astro racing, the kit Medium arms are fine.
Same as for the front, while racing on high grip, the 2mm sway bar is a good option to have.
As asked a couple times after my previous post, I am running both sway bars cut shorter and then using the same mount system as on the XB2’24. With this I can set the sway bar much more precisely and it allows it to work better on the track. Also having more clearence between the front drive shafts and sway bar holder.
To prevent any issues with the rear drive shafts falling out while playing with the width or droop of the car, I recommend the adjustable drive axles, whith which you can always change the drive shaft length to fit the current setup you are running.
You can find these option parts under the part numbers:
#323356 2x - Alu "Low" hub
#325341 2x + #325390 - 2x Adjustable drive axle + shim
#363317 + #363326 - RF and RR wider pivot holders for more stability (must be used with shorter arms!)
#363112-G and #363122-G - SHORT Graphite rear arms
#363113-G and #363123-G - LONG Graphite rear arms
#362480 - 2mm sway bar for high grip
Parts needed for the sway bar system REAR:
#302663 - Ball Joint 4.9mm - Open - V2 (8)
#303455 - Composite Anti-Roll Bar Ball Joint 4.9mm (4)
#362650 - Ball End 4.9mm With Thread 6mm (2)
#901304 - Hex Screw SB M3x4 (10)
Apart from the parts above, for the FRONT you will need:
#303454 - Ball Joint 4.9mm - Open (4)
#363651 - Ball End 4.9mm With Thread 8mm (2) or #362652 - Ball End 4.9mm With Thread 10mm (2)
There a few changes to the chassis on the new model, first one of them is the shorter chassis possibility. You can easily change to the shorter chassis configuration without changing the drive shaft angle on the rear, or if demanded, you can actually play with the overall wheelbase for different track conditions you run on. This option needs to be used with the 113mm shorter rear dog bone shaft.
The second difference on the chassis is the two holes added on the rear part of the chassis, which if used provide less flex on the rear and therefore more stability for high grip. This is much recommended if you decide to run the option carbon side guards, which I personally like the best for carpet and astro racing. These carbon side guards also save you a lot of weight, which is a key for Stock racing. If you would find yourself struggling with high grip and flipping of the car, the new optional 2.5mm chassis can be an useful solution, which I also choose for my XB4.
Not seen much is the optional graphite mixture front and rear chassis braces. These ones again provide less flex and more stability and corner speed for the car. In case you are looking for more grip, you can go the opposite direction and get yourself the medium rear chassis brace.
You can find these option parts under the part numbers:
#361276 - Carbon side guards for less weight and more flex
#361114 - 2.5mm chassis for high grip conditions
#361286-G - Graphite front chassis brace
#361297-G or #361295 - Graphite rear chassis brace for high grip or Medium rear chassis brace for low grip
#365433 - 113mm Rear dog bone shaft for shorter chassis configuration
The slipper with one-way stays the same, as it proved itself to be a great part of the XB4 success. There is a new option part for it though - the ventilated slipper plates, which help with cooling of the slipper (if you run it loose or on very high grip) and also keep your slipper pads cleaner and last longer. This is recommended for the Modified classes. The new chassis accommodates shorter chassis configuration, which like I mentioned before, needs to be used with the shorter 113mm dog bone shaft.
Now for Stock racing guys - there is a new slipper eliminator set, which saves A LOT of weight and makes the drivetrain of the car super light. Also removing any slippage, you get the maximum drive out of the car. (Keep in mind, if you get this part for your Carpet kit, you will need to include the alu/plastic front bulkhead, 65mm front dogbone and upper deck! For Dirt kits there is no need for different parts.)
As you can see, I try to run a car with the lowest CG on high grip, that’s why I use a screw with couple shims and a nut to keep my @elceram.rc ESC cables low in the part under the center slipper. With this mounting, I can easily fit the center diff as well as the slipper eliminator. You only need to make sure your cables don’t touch any moving parts.
You can find these option parts under the part numbers:
#364130-L - ventilated slipper plates for better cooling and cleaner slipper pads for MODIFIED class
#365433 - 113mm Rear dog bone for shorter chassis configuration
#364102 - Slipper eliminator set for STOCK class (+ you will need #365436 - front dog bone 65mm, #364024 - front diff bulkhead, #361176- graphite center upper deck for the carpet kit! For dirt kit no need for different parts)
First I would like to point out my mounting system for the ESC cables, with which I can fit the slipper, center diff and eliminator with no issues. You only need to make sure to keep the cables away from any moving parts and have the nut tight (can be used with thread lock) to make sure it does not come loose. I am using 7mm of shims under the nut and a diff shim which I cut a little shorter not to touch the spur gear.
The second part of this post is related to shocks. (This section has been copied from my XB2'24 Pro tips)
The new kit has seen a big step forward with changing to the 13.2mm diameter shocks. This helps get the car the needed pack for good landings, while allowing you to run thinner oil to generate grip and keep consistency during the run.
In the kit you will find 2mm and 2.5mm versions of the pistons with 1.6mm and 1.8mm holes as the base setups. (2mm for dirt and astro, 2.5mm for carpet.) Although in case you would like to step up the game even more, I recommend to get the new optional Precision ground pistons, which is a set of 4 predrilled pistons, which you can set up as you like (2-hole, 3-hole, 4-hole configurations…) and fit in the shock body "precisely".
The new optional shock ends play a big role in the setup of my new car. With the possibility to keep the same shock rod length, but change the droop only by putting the +2 or +4 shock ball end, makes quick changes and adjustments much easier. I like to run a lot of droop on the cars, so this is a better solution then having the shock end unscrewed all the way and then loosing the thread.
To accommodate lower ride height, which is a must for carpet racing, I then recommend the optional Alu shock spring collars in the versions of -2mm or -4mm, depending on the ride height demanded.
You can find these option parts under the part numbers:
#368011 - Set of shock ball joints +2mm and +4mm
#368022 or #368023 - Alu shock spring collars -2mm or -4mm
#368033 or #368034 - Precision Ground shock pistons Blank 2.5mm or 2mm
