Released earlier this year, the Formula Q32 has proved very popular with our customers. The Q32 chassis offers that balance of punchy acceleration and fast steering that is so popular with indoor racers. Back in February we looked at circumventing the whole battery charge time issue (and also took the chance to fit an FPV camera and transmitter) but in this blog we will be looking at improving the performance of the car with standard factory parts.
What is the point of this kit?
We will be modifying a standard Formula Q32 chassis but these modifications are relevant to all Q32 models. The 'high speed gear set screw' offers adjustment in performance from the stock setup. It enables you to tune the drivetrain for acceleration performance or just top speed. It also offers replacement steering arms to set the car up to be twitchier than the standard setup. Potentially to keep the retail price down (but also because it is beyond the interest of most consumers) HPI does not provide alternate gear ratios and toe adjustment components with the standard chassis. It makes for a nice upgrade that extends the potential (and effective life) of a relatively simple model.
A pair of (tiny) grub screws and Allen wrench for their installation
To complete the installation you will also need a #1 cross-head screwdriver and a pair of small tweezers. Just as a quick reminder of how small the internal components of these cars are, here is an AA battery for scale.
How do I install the High Speed Gears set?
The HPI instruction sheet is clear and simple to follow, should you misplace it, it is available online here. You need to remove the rear chassis and trailing arm setup. We found the easiest way to do this was to remove the two rear screws and the screw infront of the led before lifting the rear edge of the top shell up and slipping the trailing arms out. You need to be careful as the rear end will still be connected via two very thin motor wires. Once removed you can split the rear housing apart via the two retaining clips and remove the rear axle as seen below. With the rear axle removed the motor and pinon gear can can be slipped out of the rear housing. The standard 12T pinion gear can be seen in line with the 8T, 10T and 14T gears provided in the kit. To remove the pinion gear, slide the tool in-between the motor and the gear and lever it off of the motor shaft. The tool is also used to re-install the pinion gear, holding the cog in place whilst you carefully re-insert the motor. The last element to remove is the spur gear; It is held in the rear housing with a long cross-head screw, once this is removed use tweezers to pull it out of the housing. With the pinion and spur gears removed from the car (standard parts denoted by the orange band in the photo below) you can see the three extra ratios the kit provides. The far left combination will offer the greatest acceleration whilst the far right the highest top speed and they should be installed in the pairs shown.
Real world performance
To compare the performance of the gear combinations we marked out a 300cm strip on a wooden floor with a (relatively high- speed) camera watching the strip. The body and wing of the model were removed to provide data unbiased by aerodynamic effect ;)
As per the above photo, the car was fully charged each time (via the transmitter) before making multiple runs over the course from the white to the black line. The three fastest runs were recorded then the top speeds averaged.
8 : 28 Ratio = 2.93 mph
12 : 24 Ratio = 3.30 mph (Standard)
14 : 22 Ratio = 3.31 mph
As you can see according to our tests the new 'top end' ratio made a fractional difference to the actual top speed. Further testing needs to be performed to see if a longer run-up reveals a bigger difference. It was interesting to see the 8 : 28 ratio was only 12% slower despite it feeling markedly so in use. This is not to say that the the 8T/28T has no place in the car. It would be the ideal limiter for a particularly twisty course or someone looking to eek out the differences in chassis setup.
How do the stability adjustments perform?
Toe adjustment
The main focus of the stability adjustment is to provide more toe-out to the chassis. This will give the car more responsive steering at the expense of some straight line stability as explained in the installation excerpt below. The standard setup runs effectively parallel with zero toe, so the wheels point forward when the steering is in the dead ahead position. HPI supply two pairs of shorter track arms (marked -2 and -1) that will toe the wheels out, to say it will point the front wheels slightly away from each other. To fit them you will need to remove all of the screws above and below the chassis. At that point you can lift the top of the chassis lid up and lift out the steering system, being careful not to knock the return spring loose. As per the instructions (and seen in the photo below) you will want to use the sloped separator portion of the tool to pull the 'track rods' off of the hub 'ball joints'. To test the difference, we re-fitted the -2 arms which really tow the steering in and rebuilt the chassis. In practice we found this (combined with the standard ratio gearing) made the car really twitchy. Any slight steering input would have the car cutting in hard and often spinning out. We feel this setup would only be suitable for the slower gearing combos (8/28T and 10/26T) where it would be easier to maintain control!
Tweak screw
The tweak screw set was much simpler to install. It effectively adjusts the turning circle of the chassis (presumably by stiffening the spring effect of the swing arm). Using the included Allen wrench, insert the tiny grub screws into the bottom of the chassis. If you find your car is slightly unbalanced out of the box (ours was quite aggressive at left hand turns) you can tighten one side up to widen the turning circle and balance it up. Amusingly this simple, cheap modification made the most 'real world' difference to the driving enjoyment of the chassis.
This still isn't good/fast enough for me
Whilst more POWER is normally always better, we would question it in such a small and light chassis! The motor is small but not quite the same dimensions as those used in our Tiny Whoop's thus a swap will take some research. The rear axle bearings are plastic and we have seen others swap in 620 size bearings in an attempt to smooth out the drive. The other option is to up the power input. Following our previous blog you can retrofit the Q32 chassis with a power plug to avoid the long charge times associated with the standard setup. Using a similar method but a different plug would enable you to throw 7.4v or even 11.1v at it with a 2 or 3 cell battery; But we'd estimate this would burn out the standard motor in minutes if not seconds. As such we'd suggest graduating to the next size up with one of our 1/18th scale electric models. If you have made your Q32 markedly faster or more powerful we'd love to hear from you via social media.
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With years of experience both selling and supporting HPI’s electric range, when it comes to HPI Racing you know you are in safe hands dealing with us. Take a look at the 600+ listings we have for them alone! Do you have any questions, or have you spotted errors in the article? Do you have any experience modifying a Q32? We welcome advice and feedback, so please leave us a message in the comment section below!
Written by
Tom Begley
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