VS6075 lap times out-of-sync with other historic series

[gordon]

Hi Guys,

Following our very fun-filled first run of our historic series classes Historic Saloon, American Pony Car and Vintage Sports '60-'75, one thing stands out for me - the latter is still too fast for the period. Here are the fastest times posted for all classes run so far in 2017:



APC and HS are in the 7-sec bracket, which is great. While I believe that VS6075 should be faster than these two classes (perhaps around 6.3-sec), it is actually closer to our "modern-day" classes Modified Production and Restricted GT. I would really like to slow them down to over 6-sec, but it should be done with the consensus of all current competitors in the class.

Please let everyone know your thoughts on this below in the comments (whether you feel they should be slower or not and what suggestions you have for slowing them if you feel they are too fast).

Gordon

[gordon]

My suggestion:

All magnets must be at least 4.0 mm ahead of the front edge of rear axle.

This is not an arbitrary figure. It happens to correspond with the front magnet position on a Slot.It motor pod. Cars which do not have a Slot.It pod can still have their magnets positioned to follow this rule.

That's it. No other change. I'd like to test a car with a Slot.It pod and one without one to see the effect. Aiming for 6.3 to 6.5 sec lap times. If my cars run those at best, Ramesh's should be just over 5.999 sec .

[steveaca]

I agree with you about the times Gordon, and also with your suggestion about changing the magnet location regulation. Very simple and, hopefully, effective.
Steve

[gordon]

Well I prepped my SC and RC cars today. When they were done I took a break for a few hours then decided to change the setup in my VS Slot.It GT40 as per my suggestion above. Initially, I just moved the magnet to the forward magnet position on the pod but it wouldn't pass the USD test. I thought of shimming the magnet to get it a slight bit higher off the track but since I have several Slot.It magnets, I changed the flat (no grooves) higher-downforce one I had on for one of the new magnets with the grooves and it immediately passed the USD test.

I fiddled around with magnets, lead and tyres till it consistently passed the USD test, so I'm ready to give it a try at the next event to see what times it does. I have some other thoughts/theories about the best setup for classes where magnets have to be in a more forward position but I need to do some tests to see what's right and what's wrong with them. It's great having the option to experiment with these settings.

[RameshB]

Hi i am on the same page with this suggestion and i know the objective is to seperate classes and get the average times as close to the actual way the cars perform. I also had a closer look at my NSR gt40 and the SW motor pod factory mag position is just like slot it. I am happy with this new suggestion it will definetly slow the cars down and have the back coming around a bit. I will also try setting up one for next race day.

[gordon]

Following up on this topic, here are my specific regulation change proposals for addressing this issue. These are the current Vintage Sports '60-'75 regs (items in blue are changes implemented for 2017):

Vintage Sports '60-'75 (VS)
For slightly modified slot models of racing sports and prototype cars from 1960 to 1975 - see Eligible Cars below.

• Body: See Eligible Cars below. Body must comply with General item 2. Windows may not be tinted - interior must be visible.
• Chassis: May be substituted by a chassis which uses a Slot.It motor pod that is designed specifically for that model. Substituted chassis that are adjustable are not allowed.
• Minimum Ground Clearance: 1.0 mm / 0.040".
• Interior: Full interior as standard for the particular model, however this may be altered if necessary, but only to the extent required to install digital chip. Must comply with General item 3.
• Digital Chip: Free.
• Motor: 22,500 RPM or lower, based on manufacturer's specifications.
• Gearing: Motor and axle gears may be changed.
• Motor Pod (where applicable): Inline or sidewinder only.
• Magnets: USD rule. Magnets must be positioned in one of the standard magnet locations for the particular model (in the case of standard chassis) or motor pod (in the case of substituted chassis).
• Wheels: Standard size for the particular model but may be substituted by aluminum or plastic wheels. Wheel inserts that match or are close to original wheel design are required.
• Axles: May be substituted but must be solid steel.
• Tyres: Free.
• Guide Flag: Free.

Here are the proposed changes in red (just two):

Vintage Sports '60-'75 (VS)
For slightly modified slot models of racing sports and prototype cars from 1960 to 1975 - see Eligible Cars below.

• Body: See Eligible Cars below. Body must comply with General item 2. Windows may not be tinted - interior must be visible.
• Chassis: Free.
• Minimum Ground Clearance: 1.0 mm / 0.040".
• Interior: Full interior as standard for the particular model, however this may be altered if necessary, but only to the extent required to install digital chip. Must comply with General item 3.
• Digital Chip: Free.
• Motor: 22,500 RPM or lower, based on manufacturer's specifications.
• Gearing: Motor and axle gears may be changed.
• Motor Pod (where applicable): Inline or sidewinder only.
• Magnets: USD rule. Magnets must be positioned at least 40mm ahead of rear axle.
• Wheels: Standard size for the particular model but may be substituted by aluminum or plastic wheels. Wheel inserts that match or are close to original wheel design are required.
• Axles: May be substituted but must be solid steel.
• Tyres: Free.
• Guide Flag: Free.

40mm is exactly the location of the frontmost magnet location on a Slot.It motor pod.

There are only a small number of us preparing and racing these cars at present. I'm sure we can all come together and discuss this and make a decision.

[obrie]

Good idea. I will try to prepare one as well

[gordon]

I now have three cars prepared this way. More on the way.

[gordon]

Had a chat with Ramesh yesterday about this topic. He pointed out that the Slot.It Alfa 33/3 and Ferrari 312 PB would not be competitive against the Ford GT40 if we use the fixed 40 mm distance suggested because these have shorter chassis than the GT40. I had a detailed look at the two chassis and he's right in that, although they have almost identical wheelbases, their difference lies in the relative location of their guide flag pivot points. The GT40 guide flag is substantially further forward than that of the Alfa and Ferrari. This is where the implementation of the magnet location for Historic Saloon and American Pony Car is the best idea to equalise cars with different dimensions. It is really the distance between the rear axle and the guide flag pivot point that affects handling (the famous triangle comprising the two rear wheels and the guide flag). The front wheels are just there for stabilisation and realism. They play very little in the final handling of the car. Have a look at this image of the Alfa and GT40 chassis:



Don't let the coloured lines confuse you. I've explained each on the right side of the image, so just go through these explanations from top to bottom. Its pretty clear once you do.

I've always been for an inclusive rather than exclusive policy when it comes to as many different cars by as many different manufacturers as possible. This system using the rear axle and the guide flag pivot point in conjunction with the USD rule is the best option that I have seen to date to accomplish this so that as many cars as possible are included with a fair chance of being competitive.

[RameshB]

Hi Gordon your diag. were very helpful and your exp. were very detailed, thanks this will help a lot. much appreciated.