Fairways Racing Complex Forum

Hi Guys,

I've continued to put a great deal of thought, a lot of time and research and even some minor financial investment into trying to get our Historic Saloon, Vintage Sports and Restricted GT classes under control and as fair as possible on track for all competitors. I believe I finally have a fair solution for ensuring that we're all racing "apples against apples" and not "apples against oranges".

The changes involve the two most significant items that affect performance, motors (power) and magnets (handling). I have what I believe is a simple solution to address these two items and keep cars in line with the regulations, yet competitive with everyone else.

Please see the revised class regulations for these three classes. I've added an identifier to the end of the class names to differentiate this formula from the previous one. This will effectively start over the "Fastest Lap" record, reflecting the fastest times based on the new formula.

Policing

To police these changes - and to set up your cars to be both competitive and legal - requires some hardware, one of which I already have access to (thanks to O'Brie) and the other which I'll have next week.

Motors

Motor RPM will be checked using a digital strobe tachometer and a disc/flywheel. This should be able to be done directly off one of the rear wheels then multiplied by the gear ratio. For example, if the rear wheel RPM is 7,000 and the ratio is 3:1, motor RPM is 21,000. We will allow a 5-7% leeway for motor performance variation (especially for properly broken-in motors).

Magnets

Magnetic downforce will be policed using O'Brie's Magnet Marshal. Again, we will allow a 5-7% leeway when checking cars.

Gordon

Hi Gordon,
I think the new rules certainly would achieve the desired 'apples vs apples ' result and it would be easy to check for infractions with the Magnet Marshall and new 'tachometer' but I also think that there are now some not necessarily desirable effects, particularly in HS. Some of these are:
1) The HS class will now become a modified class. As far as I know, none of the Scalextric HS cars (either FF or FC130) comes standard with a 21,500 rpm motor. To now be a front runner would mean a motor change as cars in present configuration would not be competitive (speed wise) with, say, a Scaley BMW Mini with a Slot.it 25 k motor. In my case (SCX Fiat 131), I cannot even fit an FC130 type motor without some sort of adapter so I'm stuck with an SCX RX42B 18k motor. My suggestion would be to allow only stock motors( the rpm of which can now be checked) up to a limit of 21.5 k rpm in cars so fitted as standard equipment. The majority of cars now competing would fall in the 18 k range anyway. With the standard motors retained, I think that standard magnets , as at present obtains, can also be retained. I think the new magnet rule could be applied to cars which have motors > 18k rpm.
2) While the naw magnetic downforce limitation would be fair (and easy to check), I can forsee difficulties in setting up cars once away from FRC. Someone may test and see that adjustments are necessary to comply with the rules but these adjustments , in many cases , would need to be performed at the home garage . This adjustment would then be a hit-or-miss operation not many racers would have a means of measuring magnetism. Even if one were to get it right once, there are several variables which could throw this off. A simple thing such as a change of braid could raise or lower a car to the extent that the magnetic reading could be affected. Again, my suggestion would be to leave the magnet rule as it is, whereby the standard magnet must be used (except for R-GT which allows a change but the standard location must be retained). I think it is easy enough to get data on at least Scalextric specs. so if any car is scrutineered, one could just check magnet dimensions to ensure that they are standard.
3) If the only restriction to magnetism is an absolute number, as now written, it would mean hours of testing to set up any car optimally as one could use any combination of magnet sizes and placements , once the total magnetic downforce limit was not exceesed. This would increase difficulty of getting the best performance out of these cars.
Please let me know what you think.
Steve

Steve,

Let me adress each of your points:

1. Scalextric FF motors are officially rated at 18,000 RPM. You can have a look at their Ford Escort specifications as an example. Yet, the Scalextric W9049 FF motor found in modern F1 cars has no RPM info on the Scalextric website, however it is rated at 22,500 RPM on Electric Dreams. The MRRC FF motor used in all Sebring chassis cars is rated at 21,000 on the MRRC site. The bottom line appears to be that there is a range of anything from 18,000 to 22,500 possible for these motors (excluding those rated under 18,000 like in the Scalextric MGB). If cars using these motors are raced with 18,000 motors, we're going to get a performance difference between them, exactly the reason why we allow the Slot.It 21,000 RPM motors in Vintage Sports. To simplyify things, I felt that setting a 21,500 RPM limit for all cars would be the best solution. I do not believe that the 21,500 RPM limit makes the class a modified class since we already have cars running in HS with motors in this range (its not like we're allowing 25,000 RPM motors). In the case of your SCX car, the Slot.It SP08 adapter (US$3.99) will allow you to install an FC130 motor if you find the need for it.

On the magnet point you raised in connection with different motor RPM, my initial reaction is that the suggestion over-complicates checking cars. I feel magnets should be addressed separately as you did in points number 2 and 3, so read on.

2. / 3. I agree with there being difficulty in setting up cars without having access to the Magnet Marshal (MM) and I did think about this issue. It may be a hassle initially, but I feel that once a car has been set up, it should retain its MM reading unless something like tyre height changes. We can have some more test days to assist everyone with getting their cars set up (me included). On race nights everyone will have access to the MM to check their cars and make any necessary alterations to ensure that they comply. My reason for just putting a maximum downforce limit is first and foremost for keeping the cars' performance on par with one another, but also, by allowing any magnet location and quantity, it can make it easier to adjust the set up to get in line with the regulation maximum downforce. In most cases the ideal setup quite likely will be a single (standard) magnet in a standard location.

In summary, my reason for these changes is to bring the competition back in line and stop things from getting out of our control. If other practical and enforcable suggestions can allow us to achieve these, I'd be happy to go with them.

Incidentally, I have started to compile a database of magnet readings and several of my cars' magnetic downforce will have to be reduced to comply with the new regulations. The resulting reduction in handling will reduce the motor varation affect in lap times since cars start becoming harder to drive with more power and less downforce. Here's the info I have so far:



Gordon

Guys,

I'm thinking of reducing the maximum MM downforce in Vintage Sports from 300 gms to 275 gms. If reduced, the MM limits for the three classes will therefore be:

• Historic Saloon - 200 gms
• Vintage Sports - 275 gms
• Restricted GT - 325 gms

I have to do a bit more testing and measuring before finalising the VS limit.

Gordon

Hi Gordon,
I note that in 'Slot Car News' where they have actually tested motors, that the Scaley FC130, rated at 18 k rpm, has actually been tested at between 20,500 and 22,300 rpm, with a power output of 5.3 W and torque of 99 to 104 g.cm. Similarly, the Formula 1 FF motor, again rated at 18k rpm, has been tested at 22,800 rpm with a power output of 8.3 W and torque of 147 g.cm.
Based on this, I would agree that the HS class should be allowed motors of 21,500 rpm, as to limit them to 18,000 rpm would mean almost certain failure by the majority of cars in this class. What I think however, is that the only motors allowed should be those fitted as standard equipment . This would in no way adversely affect the majority of cars in this class which fun the Scaley FF motor (Escort, Cortina, Torana), the few FC130-motored cars (Scaley BMW Mini, Fly Alfa Romeo) or even fewer others (SCX Fiat 131). The majority of cars in this class at present are fairly evenly matched as it is. To allow an FC130-motored car to change to a Slot.it 21.5 k motor, would shake things up drastically. The Slot.it 21,500 rpm motor has been tested at between 22,500 and 23,700 rpm, on the face of it not a whole lot more than the tested readings for the Scaley 18k motor. The big difference however, is that the Slot.it has power and torque outputs of 9.1 W and 170 g.cm respectively, > 60 % more than the Scaley.
In VS, I think that the allowing of cars to upgrade to the Slot.it 21.5 k motor is OK as this motor is standard anyway on the Slot.it cars allowed in this class. To not allow this change here would be to put the other FC130-motored cars at a disadvantage.
As far as the magnetic downforce limitations go, I'd be quite willing to give the new rules a shot. I'll certainly be bringing some of my cars to the next FRC event to get some readings.
Steve

Steve,

I had forgotten about the Slot Car News' motor page. That's a really good resource for any slot racer and it certainly adds food for thought to the point in question about just limiting motors based on RPM alone. For everyone's benefit, here's the web page we're referring to:

Slot Car News Motor List

Based on the information presented, I agree with your suggestion. Motors in Historic Saloon will remain as "Standard for the particular model" with an upper RPM limit of 21,500. However, in view of the Slot Car News information, this 21,500 RPM figure may have to be increased. I'd like to get some feedback and suggestions from all FRC drivers on this, so please chime in below.

Gordon

Gordon,

You have done a lot of work to overcome some challenges in order to have all the cars competitive. There are too many point to understand and focus on in this post. I do have a lot of questions and I think it is best discussed when we race next. Set some time aside to have an open discussion.

I do understand your plight to have all car with similar characteristics, however you are making it more difficult for all drivers and yourself. One must remember this is a fun track and your rules are good. Only one class is questionably with regards to GT40. This car should be looked at and checked weight. When you start talking about downforce you have changed the game for everyone.
You know in the real world suspension is one of the key to winning races. I understand stating a magnet size but downforce is a different ball game.

I think making all these changes will hamper your racing especially since we don't get a full turnout at every meet. It may be a deterrent more than fixing a small issue.

Arden

Hi Gordon,
you're probably correct in that the rpm limit may have to be changed. Based on the tests by Slot Car News (22.3 k rpm and 22.8k rpm for Scaley FC130 and FF motors respectively), I think a limit of 23,000 rpm would be suitable. Man, I didn't realize how fast those stock Scaley motors could be !

GG - When I saw your post on Saturday I was thinking how to respond but will have to say now...

Information Overload and (sorry to say) its kind of freaking me out too

One question came to mind though while trying to absorb all this info ~ Why include RGT in all this, when its one of FRC's most straight forward slot car builds.

I could understand why with the HS & VS classes, when you look at the racing regs.

Sincerely,

Luke

Hi Luke,
as Ian Alleyne says, "Doh hut yuh head". I know that there has been a bit of to-ing and fro-ing of
information but it has all been in the interest of arriving at the best solution for these (HS and VS) classes. Once arrived at, policing (is it politically correct to say that ?) the rules would be very easy to do.
Steve