Improving the Performance of Your Scalextrics Cars

Scalextric is a brand of slot cars, those little toy cars that race around a groove in a track. They were released in 1960 (You should check out some of the vintage Scalextric sets if you haven’t seen them!). So these improvements to Scalextric sets will probably work with most slot cars but just so you are aware they are focused and design for Scalextric.

Now I’m a big believer in you should measure before you improve and in this case it a fun too! So grab some track and build a simple course the cars can’t fly off at high speed. Grab to cars and get them to race around at the highest speed. If they don’t finish at the same time have a go though a few of your cars until you find two that do. That’s our baseline! So do the modifications below to only one car and one side of the track and see the difference.

Now before you go modifying anything make sure you aren’t messing with any Vintage Scalextric cars. These can bit worth quite a bit of money in their original form so don’t mess with them. Hell, send them to me and I’ll send you two new ones 😉

So let’s get Modifying! When thinking of how to improve performance in a Scalextric car it’s the same as what you would do to improve your own car, better motor, tires, roads etc. In fact if you know anything more about cars than I do (and that’s probably likely) then you probably have a few more suggestions that I do so please send them on but here’s some that you can try.

Let’s start with the car because that’s where you can get the biggest benefits. Let’s start with the best mod, a new motor. The motor that comes with you normal cars runs at X revolutions per minute (rpm’s from now on) but you can get motors of the same size that run at up to Y rpm. So you can take out your old motor and put a new one in. Of Course the fast your motor goes the fast your car!

The next thing you can do is improve the gears. Your normal car runs faster in 5th than 1st right? And so will your Scalextric car runs faster with different gears. Gears change one rpm at the engine to a different rpm at the wheels. Now you can’t be in the cars changing gears like your normal one so the so have one set installed. But you can pull them out and install a different set. If you’re old gears meant that one revolution of the motor turn the wheels twice and your new configuration means they turn four times then you’ve just doubled your car speed! Be careful though, your motor only has some much torque/ power so if you gear it to highly the motor will not be able to handle it and your car won’t make it up any slopes or worst yet not move at all. It may take a little experimentation to get it right for your motor.

So now you’ve ramped up your rpm but some of your power is wasted on friction. The only thing you want the motor to be doing is to be turning the wheels against the road (the bit where you want friction) but it also turns the axles and gears against their bearings, and you don’t want to waste power here. So you need to reduce the friction as much as possible. You can do this by installing better bearings, which works great but is a little hard to source. You can also add lubricant the existing bearings and gears to reduce the friction. Or better yet, do both!

Just as we tried to reduce the friction where we didn’t want it we want to try and add it where we do want it – the wheels. It’s not good getting you tires spinning twice as fast if they just skid on the track and your car doesn’t move forward. To improve this you can get high performance tires and swap them for the ones you have on. They grip the road better and make sure your rpms are turned into kpms aka speed. Also, normally included in the cars design so there’s not much you can do about it, but you can add fins etc that use the wind against the car to push the car tight to the track increasing performance again.

So now you have your car running pretty fast – probably as fast as you can practically make it go; now it’s time to look at the track. Like the tires on the cars you want a high amount of friction on the track so the combined grip of the tires and track make for a great grip, the highest friction possible and the no lost rpm’s. Scalextric has a new sports track out designed to do that but there is some DIY you can do on your own track. One simple thing you can do is make sure your track is clean and clear of dust. As you can imagine dust on the track is like driving in mud and your car will slide.

Once again you’ve added friction to the track, now you want to remove it from anything unnecessary. As the car run around the track it runs on a slot. That slot in most homes is a natural place for dust and debris to collect and the car has to push through it to make its way around the track and it loses speed doing that. So clean the slot of the track regularly. I adjusted one of my cars to do it for me, adjusted the gears so it went slowly with a lot of power and put some replaceable tissue around the post that goes into the slot. Then all I had to do was drive it around once or twice! The other place where you can get friction in the slot is the track joints. If joints are lose or don’t line up the car to bump a bit as it goes through and this slows it down too. Quite often the metal connector between the tracks bend a bit and creates a bit of a disjoint. Bend the metal back into place and make sure the connection is not loose.

Last and probably least, the power to your car comes through the track to your car. For the more speed you want more power so you want to make sure it is all making it to your car. So check the contacts are all clean and not loose so there are no gaps in the power supply.

Now comes the time to test again. Get the same cars on the track and race them again, improved Vs original. If you don’t notice a huge difference (then you have probably done something wrong 😉 )I’ll eat my pants.

Cold Air Intake Systems And Coilovers For Improved Car Performance

We often wish that our car can do more. And with this in mind, we often consider taking it to our trusted mechanic and see what modifications we can introduce to it. There can be several, and all these can cost us a large sum of money. In many cases, we would try to weigh things and end up asking ourselves if the investment we make would really be of value. What many of us do not realize is modifying our car does not need to be too costly. We can simply introduce small modifications like installing a cold air intake system or a coilover to give its performance a good boost.

You might be wondering what a cold air intake system is or what coilovers are. You need not be a rocket scientist to understand what these aftermarket auto parts are and what they do. Also referred to as a cold air induction system, cold air intakes are installed into the internal combustion engine of a car to allow cool air to get in, making the engine become less prone to overheating and increase its performance.

Coilovers, on the other hand, are introduced to cars to lower their center of gravity. They are much like shock absorbers but they are not necessarily shock absorbers. Getting confused? Not to worry – a coilover is actually short for coil spring over strut and is a type of suspension system. Unlike the stock suspension system, it allows more room for adjustment so you can lower the body of your car to your preferred height. And with its center of gravity lowered down, its handling is obviously improved.

With these two aftermarket parts, the performance of your car can already be greatly improved. Come to think of it, cold air intake systems make your car run faster but you might be worried about its handling. Now this part can be taken care of by coilovers, which help in improving the handling of cars so you do not have to worry much about having difficulty in controlling the car at maximum speeds.

You might not be dreaming of becoming a car racing star but it definitely makes a big difference if you travel on your car at its peak performance. Try to consider adding these two aftermarket parts into your vehicle and feel the difference of the improved performance of the your car that you thought is just another suburban vehicle.

Utilizing Nitrous Oxide to Boost Your Supercharger Performance

There comes a point in your power buildup where you may consider adding nitrous oxide injection to your supercharged car. This point typically coincides with reaching a level of performance that means increased investment and diminishing returns from your supercharger. For example, my car comes from the factory with a 5th generation Eaton MP45 supercharger. This supercharger is limited to about 230hp worth of flow rating and so no matter what I do with bolt-on upgrades on my engine, my peak horsepower will not exceed 230hp limit because that is the point at which the supercharger becomes the bottle neck in my system.

As we’ve talked about in previous articles there is still the option of porting the factory supercharger for a 10 to 15% gain in capacity (which in this case would be another 23 to 35 horsepower). There is also the option of retrofitting a larger supercharger such as the Eaton M62 to gain potential up to over 300hp depending on the final choice of a supercharger.

This modification path (porting or replacing the factory supercharger) can prove to be complex and costly, especially if the supercharger is integrated into the intake manifold (and possibly an air to water intercooler) as the case is with many factory supercharged cars.

A possible viable solution for this situation is to use nitrous oxide injection to supplement the power delivery when racing, and being satisfied with a reliable lower powered car when the nitrous is off and we’re not racing.

The reason why nitrous oxide (N2O) becomes a great power adder is twofold:

1- Nitrous is cheap as far as horsepower per dollar goes, and especially in the situations where we’re already supercharged and so will only be using it on the rare occasions when we do hit the track.

2- Nitrous oxide is a great ‘chiller’ as it comes out of the bottle at a temperature of negative 127*F and is capable of cooling the overall supercharged air charge mixture by over 100*F as reported by enthusiasts, this is an additional temperature reduction over the effects of whatever intercooler you have fitted. This in-fact makes nitrous a great proposition for cars that have already maxed out their superchargers, where the supercharger is running at peak rpms and producing very high outlet temperatures. The nitrous oxide injection can effectively boost the thermal efficiency of the supercharger when it is most stressed out and give us a nice, cool, and dense mixture.

3- Nitrous oxide fuel delivery is fairly straight forward to setup and to tune, especially on newer model cars with return-les fuel systems, or difficult to crack computers that make it difficult to upgrade (and properly tune) a much larger supercharger setup. Nitrous oxide fuel delivery can be set-up totally independently from the OEM ECU and fuel system and thus makes nitrous a possible application for German cars with stubborn computers.

4- This is a racer technique… most cars seem to perform better during the winter months because the air is cooler, horsepower is elevated, and the tracks although cold, can be prepared for traction and will heat up enough during the night to allow for traction and to give people the ability to exploit the cold dense air to post their best times of the year. As the weather gets warmer, traction increases because the asphalt is warm and sticky, but horsepower is reduced due to warmer, less dense air. Typically racers find that their cars vary in their quarter mile performance by as much as a half a second between their summer tune and their winter tune, especially if you’re using a supercharger or turbocharger that compresses (and further heats) the incoming air.

The solution to on-track consistency, racers have found, is to combine the use of nitrous oxide (which is summer friendly) with forced induction (superchargers and turbochargers) which are winter friendly. In the summer time, the outside temperature is high, and so the nitrous bottle pressure is maintained at a high level above 1100 psi. This allows for a generous nitrous flow rate under the sustained pressure (even without a bottle heater) which gives great summer performance for nitrous assisted cars. While in the winter, the outside temperatures drop significantly, the nitrous in the bottle contracts and the bottle pressure drops, subsequently, the nitrous flow rate drops and nitrous assisted cars show worse performance in the winter times.

The complete opposite is true for supercharged cars that produce great horsepower in the winter from compressing cool dense air, and poor horsepower in the summer heat. When you combine these two power adders you get pretty flat and consistent horsepower production year round because the supercharger shines when the nitrous is weak, and the nitrous shines when the supercharger is weak, and thus together, they give consistent power deliver year round.


Now we have to consider that nitrous oxide is an oxidizer and thus not only does it increase the amount of air and fuel combusting in the cylinder, but it also produces a faster moving flame front due to the oxidizer properties of the nitrous oxide. This means that additional timing retard, great octane fuel, and possibly colder spark plugs will be required to run spray on a supercharged car. Furthermore, because of its cooling effect, a 100hp shot on a supercharged Camaro can very easily put down OVER 120 rear wheel horsepower of additional power. This means that the ‘out of the box’ jetting of a nitrous kit may not be adequate on a supercharged car and you’d have to make sure to monitor and possibly increase the fuel jetting to match the final horsepower figure of your car). Last but not least, if you’re running a 500hp supercharged car with an additional 120hp of nitrous oxide injection, then you must make sure that your fuel delivery (fuel pump and fuel lines) are able to flow the total amount of fuel required to deliver 620hp.

Applications scenarios:

1- You have a car like mine, a 2005 C230 kompressor that comes with a 230hp limited Eaton MP45. ECU on the car is a Siemens ECU that very few people know how to tune, and the fuel system uses a return-less setup with an in-tank fuel pressure regulator. With this kind of setup all forms of dry nitrous injection are out of the question because we can neither compensate for fuel through flashing the factory ECU, nor can we elevate fuel pressure during the nitrous injection because the fuel pressure regulator is in-accessible….

Recommended kit:

A wet nitrous injection kit that injects both fuel and nitrous oxide from the injection nozzle.

Injection location:

After the supercharger, after the intercooler, and into the intake manifold of the car.

Maximum recommended injection:

25% of the original total power figure which corresponds to around a 50 hp shot of nitrous on our example.

Expected final horsepower:

60 to 65 wheel horsepower and possible about 130 ft-lbs of additional torque!

2- You have a car that has an accessible fuel pressure regulator, or an ECU that can be re-flashed for nitrous oxide or a ‘dual tune’ setup. In this case it is recommended to use a dry nitrous kit for two reasons:

First: Dry kits are safer on supercharged cars (as long as the fuel delivery through the injectors or raised fuel pressure is adequate) because they hold a reduced chance of intake backfires because the intake manifold is dry of fuel.

Second: Dry nitrous injection contains no fuel, and so we don’t need to worry about fuel falling out of suspension from the injected air. This means that we no longer have to spray the nitrous right before the intake manifold and we now have the option to move the point of injection much farther back. Spraying nitrous BEFORE the intercooler, right after the supercharger gives the nitrous stream more time and more contact with the compressed air coming out of the supercharger which results in more cooling and further increased horsepower.

Recommended kit:

A dry nitrous injection kit that injects only nitrous oxide from the injection nozzle.

Injection location:

After the supercharger, before or after the intercooler and not necessarily right at the intake manifold of the car.

Maximum recommended injection:

25% of the original total power figure which corresponds to around a 50 hp shot of nitrous.

Expected final horsepower:

70-75 wheel horsepower and possible about 130 ft-lbs of additional torque!

3- You have a car that has an accessible fuel pressure regulator, or an ECU that can flashed for nitrous oxide or a ‘dual tune’ setup. You also want to make as much horsepower as possible from your nitrous…

In this case it is recommended to use a dry nitrous kit injecting before the supercharger. As we mentioned in our articles on twin charging (combining turbochargers with superchargers for added performance), when two ‘chargers’ are chained in series where one charger feeds the next, then the two pressure ratios of the charger combine because the second charger compresses air that is already compressed by the first. For example two turbochargers set for a 1.5 pressure ratio (or 7 psi of boost), running in sequential mode will result in a final pressure ratio of 2.25 bar (or 18psi of boost) which is more than the ‘expected’ 14psi that is the sum of the two boost levels.

Similarly, injecting nitrous oxide before the supercharger, delivers already compressed air. This is true weather we are talking about nitrous being compressed because it has twice the oxygen concentration as normal air or we’re talking about the nitrous cooling and compressing the incoming air. The final amount of compression observed by the supercharger inlet will vary depending on the ratio of incoming air to the size of the nitrous shot, and can result in an increase in boost of between 0.5 to 2.5 psi!

This boost increase is in addition to the power increase of the nitrous oxide injection and so it can be an additional 5 to 25 hp.

Recommended kit:

A dry nitrous injection kit that injects only nitrous oxide from the injection nozzle.

Injection location:

Before the supercharger inlet.

Maximum recommended injection:

25% of the original total power figure which corresponds to around a 50 hp shot of nitrous.

Expected final horsepower:

75-100 wheel horsepower and possible about 160 ft-lbs of additional torque!

Things to avoid:

1- No matter where you setup the nitrous injection, make sure not to spray nitrous into your MAS air flow sensor or your intake air temperature sensor. These temperature dependent sensors, tell the ECU to advance the timing in colder conditions. As we mentioned earlier, nitrous is an oxidizer that increases the speed of travel of the combustion event and thus requires maintained (if not retarded) ignition timing compared to a supercharged only setup. Avoid spraying on these temperature sensitive sensors to prevent accidental timing advance from occurring.

2- Avoid spraying a wet kit (fuel) before your supercharger, as the wet fuel mist will damage the supercharger rotors and strip their coatings.

3- Make sure you check your air fuel ratio on the nitrous and don’t stick to the ‘out of the box’ air to fuel settings with the kit. For example an extra 2.5 psi in your intake may or may not be compensated by your stock ECU and so depending on how well the ECU reacts you will have to adjust the fuel jetting on the nitrous kit.