Johannes is back at it again with a super in-depth review of our recently released sports touring car: the Execute XQ3S! Here's what he had to say:

With the XQ3S, Xpress is launching the anticipated sports version of the XQ11 touring car released last year. The XQ3S inherits many of the features of its bigger brother, but uses a different choice of materials to achieve a significantly lower price.

Instead of carbon fiber and aluminum, the focus is on glass fiber and plastic.

The XQ3S is the successor to the XQ2S. It comes with many features that had to be retrofitted as tuning parts on the XQ2S. First and foremost, it is no longer necessary to buy a mid-engine conversion kit, as the XQ3S has a mid-engine layout straight from the kit. It is also no longer necessary to retrofit aluminum wheel hubs. These are also fitted ex works. Only double-jointed CVDs on the front axle and stabilizers are not part of the kit.


WHAT'S NEW?

Apart from a few details, the XQ3S differs from the XQ11 mainly in the choice of materials and the design of parts that are made of aluminum in the XQ11. For example, the bulkheads on the XQ3S are again made in one piece. Nevertheless, shock towers have been dispensed with and a plastic version of the LCG conversion kit has been integrated.

Compared to the XQ2S, the entire suspension geometry has changed with the narrower bulkheads and longer suspension arms. It is largely identical to the XQ11 and represents the current state of the art for 1:10 touring cars.

The rest of the differences are explained in the description of the build.


CONSTRUCTION

When you open the box, nothing new or unusual awaits you. Printed building instructions are included and all building sections are shrink-wrapped in plastic bags. This avoids too much confusion when building.

A few corrections are included with the instructions, which contain additional information or correct things that have been misrepresented. When building the rear body mounts, however, you realize that even the corrected version of the instructions does not match the contents of the kit. A small problem that is easy to solve.

SUSPENSION

Construction starts as usual with the suspension. The upper wishbones are built first. The thread into which the threaded rods will later be screwed is first pre-cut with the supplied screw. After screwing on the ball cups, the threaded rods are screwed into the wishbones. Pre-cutting is absolutely essential, as otherwise not enough force can be used to screw the threaded rods into the wishbones.

It is important to ensure that the length described in the instructions is correct and that there are roughly the same number of threads on the left and right so that it is possible to adjust them later in use without any problems.

Apart from the length of the ball joints used, there is nothing unusual to note when building the suspension links.





DIFFERENTIAL

The differential is then built. It is not only the width that has changed compared to its predecessor. Brass bushes were pressed into the housing parts to ensure better running of the drives. The other parts are unchanged. The O-rings should be lubricated with damper oil and 1.3g of oil should be poured into the differential. I decided on 5k oil for asphalt as a starting value. On carpet, you should start with 7k, depending on the grip of the track. The weight specification is used to avoid overfilling the differential and ensures that the same amount of oil is in it as before, even after an oil change. When removing the bevel gears from the injection molded frame, it is not only important to ensure that there are no burrs left, but also that there are no plastic residues left in the gears. These can quickly lead to the premature death of the differential. The pin in the deeper half of the housing is best inserted using needle-nose pliers.

I have marked the eccentrics of the ball bearings with white markings. This makes it easier to see their orientation when installed, even if the lighting conditions are not ideal. A touch-up pen is best suited for this.





SPOOL
With the XQ11, this construction stage was already the first minor hurdle - and this is also the case here. The design of the spool was changed. Not only has it been made narrower, but the design of the belt pulley has also been changed. Xpress has come up with a clever solution here. The ring on one side of the belt pulley no longer needs to be glued, but instead is clicked onto the belt pulley. This requires a little dexterity. However, the fit is perfect. The ring should be placed on one side and pushed under the brackets. This point is now held in place and further parts of the ring are clicked into the holders piece by piece. As with the predecessor, the spool outlets are first inserted and then secured with screws.


LOWER WISHBONES
After the differential, the lower wishbones are built, which are now significantly more complex than on the XQ2S. Alongside the mid-motor layout, they are one of the biggest innovations on the XQ3S. They are not only longer, but also have a completely different design than before.
After cutting off the injection residues, the balls are pressed in. Care must be taken here to ensure that the balls are fitted with a hexagonal collar on the inside of the suspension arms. It is also important to ensure that the suspension arms are correctly aligned before pressing them in. The screws are then fitted to ensure that the swing arms have adjustable clearance. The screws must be tightened to such an extent that the balls have almost no clearance, but are not jammed. There is a very fine line between too loose and too tight, but proper adjustment is absolutely essential!
This adjustment should be checked regularly. It can be assumed that the balls will gradually gain some clearance so that they should be readjusted from time to time.
As with the XQ11, the shock absorbers are attached to the swing arms via inserts in the wishbones, which can be used to change the position of the attachment. Care must be taken here to ensure that the grub screw is not screwed in too deeply.
Otherwise it will hit the swing arm itself at the end of the hole and the thread of the insert will strip.
If required, plates can be screwed into the wishbones, which are again available in two degrees of hardness, to further stiffen the suspension arm. This is particularly advantageous for tracks with a lot of grip, i.e. usually on permanent indoor tracks with carpeting.



STEERING ARMS / WHEEL HUBS

The front and rear steering arms and wheel carriers are a completely new design compared to the XQ2S. They consist of several individual components and are no longer held in position at the bottom by a pin, but by a ball head. The upper wishbones prevent tilting and take over the retaining function that was previously performed by the pin in the lower wishbone. Among other things, the caster angle can now be infinitely adjusted, but more on this later.

The bolting of the arm to which the steering linkage or track rods are later attached remains the same as on the predecessor.

The upper attachment point is fixed to the steering lever with two screws. This allows the position of the ball head to be moved further towards the chassis using spacers.

The wheel carrier has also been modified. Instead of the previous solution with a pin in the wheel axle, the driver is now pushed completely over the axle and secured with a plastic ring. When pushing on the ring, pay attention to the orientation. This has a chamfered side. This must be installed in the direction of the wheel hub. The new design also means that the dimensions of the ball bearings have been changed.

Identical ball bearings measuring 6x10x3mm are fitted in all positions in the wheel carriers.

The CVDs have also been stripped down and their design has been changed. Although they appear to be completely assembled when they come out of the bag, they have to be disassembled again, cleaned of oil and grease and reassembled. The blades on the rear end can be installed directly during this process. Unlike the CVDs on the XQ2S, the pins that hold the blade can be removed. This eliminates the tedious installation process of forcing the blade over the pin. When screwing the unit together, it is essential to pay attention to the flattening of the pin. This serves to give the grub screw a reasonable contact surface and prevents the pin from twisting. On the front axle in particular, the pin that is subsequently inserted into the spool outlets should be perfectly centered. If one side protrudes further than the other, this will cause the spool outlet to jam and the suspension will not function properly.

It is necessary to clean the CVD parts so that the Loctite, which must be used, holds properly and the screw connection effectively prevents the pin from moving. There is a lot of potential for damage here should the pin move and flail around while riding. Only use medium-strength Loctite as a threadlocker. Finally, each CVD must be greased or oiled again. CVDs running dry are quickly damaged.

As described in the instructions, the fit of the wheel axle - wheel carrier - ball bearing must be correctly shimmed. The appropriate washers are included in the kit in sufficient quantity. The axle should no longer have any clearance with the wheel driver fitted, but should not jam either. If in doubt, it is better to use one less washer and check again after the first ride.

The rear wheel carriers are constructed according to the same principle as the front ones. The rear CVDs also had to slim down and have lost material. Here too, it is important to disassemble the CVDs again, clean them and secure the grub screws with threadlocker.

As with the XQ2S, the kit does not include double-joint CVDs for the front axle. These can be retrofitted to the XQ11 as a tuning part and are still highly recommended.

Outside, you don't notice the difference so much due to the larger cornering radii, but on tight indoor tracks the normal CVDs tend to bounce and slow the vehicle down unnecessarily.







STABILIZERS

The stabilizers shown in the instructions are not included in the kit. As with the XQ2S, there will probably be a stabilizer retrofit kit, but this is not yet available. Assembling the construction from spare parts of the XQ11 makes little sense due to the price, but would theoretically be possible.


CENTER SHAFT / MOTOR MOUNT

Due to the narrower distance between the bulkheads, not only the differential and spool have become narrower. The center shaft and the belt pulleys have also been significantly changed compared to the XQ2S mid-motor kit. Instead of running on both sides of the main gear as before, both belts now run on one side. This results in a new wider belt pulley. Unlike the XQ11, where the main gear is held in place with a union nut, the XQ3S is still bolted in place. The screw connection with the aluminum ring, which is itself screwed to the belt pulley, is a good and above all durable solution - even if the main pulley is changed frequently.
As with the CVDs in the wheel carriers, the center shaft may need to be shimmed again. Some play is necessary, too much or too little is counterproductive.
Although this is explicitly pointed out in the assembly instructions, it is essential that you also use threadlocker for attaching the center shaft to the motor mount!
Vibrations occur here due to the motor and the forces during braking and acceleration, which can loosen the fastening over time.
A popular issue with the XQ2S is forgetting or omitting the stops for the battery. These should both be built according to the instructions and used as such. If this is not done, the battery will rub against the main gear and possibly its screw connection. Not nice from several points of view.




STEERING / SERVO MOUNT

The steering linkage has been moderately revised compared to the XQ2S. The bridge is now bolted to the steering arms from below instead of above as before. New screws with a flattened head are used for this purpose. These are important at this point, as normal pan-head screws would rub against the belt when turning.

Another good detail solution are the plastic servo shims or fasteners, which ensure a good hold of the servo without having to tighten the screws too much. Unlike the XQ2S, steel steering posts are now included. These are not only more stable but also ensure that the thread can no longer tear out so easily.

As always, servo arms are supplied in 23 and 25 teeth, so they should fit all common servo manufacturers. If you have confidence in your own driving skills and the quality of the servo used, go straight for an aluminum servo armature. In my opinion, the adjustable length and the increased directness have a positive effect on handling.



CHASSIS / ASSEMBLY

The instructions continue with the attachment of the suspension arms to the chassis plate. What the Xpress instructions completely ignore is the preparation of the chassis plate before assembly. Everyone has their own approach here. It is difficult to judge right or wrong here. Personally, I normally sand the outer edges of the chassis plate and then seal the end faces with superglue. With the already stiff fiberglass panels, however, this can have a counterproductive effect on the twisting behavior of the chassis plate. This time - as with the XQ11 - I did not seal the edges with superglue.

After the suspension arms, the lower bulkheads and then the motor mount and servo mount with steering posts are mounted. The top deck is then fitted. The screws are only fitted here and only tightened at the very end of the construction process. When installing the differential and spool, the position of the eccentric belt tensioners specified in the instructions works well for me. The belts are sufficiently loose, but still have room to lengthen a little without skipping.

The upper bulkheads are supplied in two variants for the front and rear end. Make sure that the short ones are fitted at the front and the long ones at the rear. The difference is clearly shown in the instructions.

The upper wishbones are then clicked onto the wishbone brackets. The connection is quite tight, which requires a lot of force when inserting them for the first time. If you want to use pliers, it is best to use the small adjustable Knippex pliers and place cardboard under the top to avoid damaging the ball sockets of the wishbones. When attaching the wishbone holders to the bulkheads, you can see how the caster angle can be adjusted on the front and rear axles. Unlike the XQ11, no shims are used on the front or rear of the bulkheads. The XQ3S only offers two positions for the caster angle on both the front and rear axle. The standard setup of 4° front caster angle and 2° rear caster angle specified in the instructions is a good starting point.

The track rods are then connected to the steering arms. It is now clear that the active rear axle is also part of the XQ3S kit. With the predecessors, the solution called OPCS by Xpress still had to be additionally purchased at great expense. This not only makes it possible to continuously adjust the track on the rear axle and achieve load-dependent toe adjustment. It also solves a problem that is often swept under the carpet, namely the symmetry of the toe at the rear axle. With some (not all) kits across XQ10, XQ2S, AT1 etc., slightly different toe values were achieved on the left and right despite identical inserts in the wishbone holder. You realized that this was not just gut feeling or nitpicking at the latest when you had to trim a perfectly tweaked chassis with the zero point set on the setup system significantly in one direction to get the straight-line running right.

Thanks to the rear track rods with the new design, this issue is also a thing of the past.

The rough chassis assembly is now complete. The shock absorbers and a few other little things are still missing.









SHOCK ABSORBERS
There are no major innovations in the shock absorbers, but they were not to be expected. The Long Travel Short Shocks have proven themselves and work well. The process of filling and fitting the membranes is well described in the instructions. Going into more detail would go beyond the scope of this build report. However: Well and conscientiously built dampers contribute significantly to the performance of a car. Air-free, the same length, identical rebound and zero play are important things that should not be lost sight of. A vacuum pump is absolutely beneficial and recommended. When screwing on the lower ball socket, make sure that the distance between the ball socket and the lower damper lock does not fall below the dimension specified in the instructions. If this is the case, the piston rod that is screwed in too far will jam the ball socket and the ball head can no longer operate smoothly.
The attachment of the dampers to suspension arms and bulkheads does not present any pitfalls. Only the shims under the ball heads should not be forgotten, as otherwise the dampers would be very flat.


BODY MOUNTS
This is the first point at which you realize that the number and length of the supplied screws is not quite right.
My kit did not contain any M3x12mm screws. According to the instructions, these are needed for the first time when attaching the rear body mount bridge.
I therefore used the 2x M3x14 screws, which are not used anywhere else according to the instructions. My feeling is that 12mm screws would have been too short at this point - so it works.
A quick look ahead to section 23: Here, too, you can see that the missing M3x12 screws are needed to attach the rear body mounts to the bridge. I still had a sufficient number of M3x10mm screws left. So I used them for this. They fit and despite the shorter screws, there are enough threads to create a secure connection.


BATTERY MOUNT
The battery mount is a revised version of the plastic spring mount of the XQ2S. At first glance, the biggest weakness of the old holder has been eliminated. However, the instructions here reinstall the weak point. Why? The old mount had the problem that the battery was only in contact with the outside of the mount at the front. In the event of a crash, the leverage developed its full potential and the battery bracket broke. Now the battery is fully attached to the front - if you leave out the front M3x6 set screw as described in the instructions. At least that's what I thought and that's what I did with the XQ11.

However, this is not possible with the XQ3S, as the battery then touches the steering arm. On the XQ11, this is made of aluminum and requires less lining around the bearing seat. Here the distance to the battery still fits. So you use the screw as intended and risk a very probable breakage, or resort to a spacer solution that ensures that the battery rests on a larger surface on the bracket. I printed a small spacer for this purpose, which also serves as a spacer for the post of the battery holder and is thus held in place.

When adjusting the battery holder, make sure that the battery has minimal clearance in all directions and is not jammed in the holder. If the chassis twists, the battery must be able to move so as not to negatively influence the twisting.

BUMPER / ELECTRONICS / COMPLETION

The bumper and body stiffener have been reworked again in the V3 variant. The bumper appears to be identical to the V2 variant. In the XQ3S, it has been given the optional strut available on the XQ10, which prevents the bumper from bending backwards in the event of a frontal impact. Unlike the XQ10, however, it is made of plastic and is therefore no longer a potential danger to the bulkheads.

The motor and speed controller can be installed without any special measures. When tightening the pinion, however, you will notice that this is no longer possible from above past the top deck as before. Instead, there is a recess in the chassis plate so that the pinion can be tightened from below. This works just as well and without having to remove the top deck.

When selecting the pinion size, make sure that the new top deck sits lower and does not have a recess for the pinion at this point. With 64dp it becomes critical from 44 teeth, with 48dp I have no experience yet. The usual 100 tooth main gear to 38 tooth pinion for 5.00:1 works without any problems.

Whoever came up with the gear ratio table printed in the instructions has probably never had the chassis in their hands. Why a gear ratio of 1.54:1 with a 69-tooth main gear and an 85-tooth (!) pinion is necessary in a touring car is beyond me. Let alone that the left-hand part of the table could be installed in any way. So once again, the table is only of limited use for finding out whether an intended combination fits the car.



FINAL THOUGHTS ON THE CAR
In my opinion, the XQ3S is a real sensation, with which Xpress has done almost everything right and better than with the XQ2S. The fact that you no longer have to buy a mid-motor kit makes the XQ3S incredibly attractive in terms of price.
 
The suspension geometry has been changed to a contemporary design that offers more adjustment options but is still reasonably easy to handle.

Nevertheless, the build of the XQ3S has become somewhat more complex compared to the XQ2S. Many things are different from what you are used to as an XQ2S driver and there are now new points to pay attention to. The conscientious construction and adjustment of the suspension arms alone takes as much time as the complete suspension on the XQ2S. Nevertheless, Xpress makes it easy to assemble things correctly and properly in many places with good instructions in the manual. The quality of the fittings was so good, at least in my kit, that I didn't have to rework or ream anywhere.

Personally, I think it's a disappointment that the actually good battery holder is once again part of this summary. With the XQ11, this could simply be remedied by omitting the adjusting screw. The XQ3S once again requires a DIY solution. The fact that the plastic feels much more brittle and harder than the previous version is already a bad sign in terms of stability in the event of a crash...

In my opinion, the battery mount is the only real weak point of the XQ3S.

The rest of the car offers an incredible number of good features, some of which were already foreseeable in advance, but which cannot be taken for granted in view of the price.

Some people will certainly describe the chassis as a cheap plastic bomber or a poorly made copy of another chassis or whatever. However, anyone who has built the XQ3S and has taken care in doing so can be sure of having a well-working chassis that has inherited many features and the contemporary chassis geometry from its big brother, the XQ11, and is definitely without equal in terms of price.


FAQ AKA FREQUENTLY ASKED QUESTIONS

My front suspension is stuck - what can I do?

- Are the bolts on the lower swing arms too tight? They should only be tightened so far that the ball heads no longer have any vertical clearance, but the suspension arms can still be moved easily and drop back down fully when they are lifted.

- If the upper wishbones are stuck, it may help to unscrew one of the ball joints a quarter turn and check again. Repeat with the other ball head if necessary. If the ball heads themselves are not 100% straight, the distance between the two will change slightly. This can cause the upper wishbone to jam.

- Are the inner pins of the front drive shafts correctly centered? If this is not the case, the pin can jam in the spool outlet when the suspension is lifted. This gives the impression that the suspension is jammed although the drive shaft is actually responsible.

I have too few or no suitable screws for the rear body mount
 
- See the body mount section in this report - different screws than those specified in the instructions must be used for this

For the sake of completeness, it should also be mentioned here that I was not given the kit, but paid for it entirely out of my own pocket.

So why do you go to so much effort and not just drive around in circles for yourself? Quite simply because I would have liked more reports like this when I was starting out. Not hymns of praise from some paid glossy magazines (which left a lot to be desired even back then), but honest reports from real-life experiences, where you can be sure that even suboptimal things will be discussed and that they will support you as best they can in your development.

I try to do this as much as possible in my reports. My attitude towards Xpress is very positive, because I personally think it's very good that there are not only the expensive competition touring cars, but also the budget version, which doesn't have to hide. Even the XQ11 as the flagship model is still around €240 cheaper than the comparable competitors.