Monday, April 8, 2013

FLYSLOT Porsche 917 LH Slot Car

By Michael Ashton

One of the numerous cars that I have gazed at longingly over the past few years is the FLY Classic Porsche 917 LH. But like many of the cars on my virtual wish list, they are simply beyond my price tolerance limit. Do a quick search on the on-line auction sites and you will see what I mean. So, when I saw that FLYSLOT (the reincarnation of the now defunct FLY company) has reissued some of the FLY Classics at a very affordable price point, just like Chief Dan George in the movie Little Big Man, "My heart soared like a hawk!".

The FLYSLOT releases of these venerable classics are referred to as the Alpha series. And they differ from their forebears in some significant ways:
  • A chassis with in-line drive train replaces the familiar side-winder set up.
  • The detailed interior of the Classics departs for a lightweight, shallow "half" tray.
  • Exterior detail is reduced slightly.
The big question is, for me anyway, does a commensurate reduction in quality and performance accompany the new lower price?


THE 1:1 CAR


The #18 Porsche 917 LH was entered in the 1971 24 Hours of Le Mans by the JWA (John Wyer) Gulf Team and driven by Pedro Rodriguez of Mexico and Jackie Oliver of England. Rodriguez captured the pole position and the team lead the race for the first eleven hours before being forced to retire due to mechanical problems (oil pressure). But in spite of not finishing the race, the #18 car has some notable distinction. The qualifying time of 3'13.9" that secured the pole position remains to this day, the fastest qualifying lap time ever recorded at the Le Mans circuit—track modifications notwithstanding. And the car's average speed of 222.304 km/h (138 mph) through its eleven hours of active competition was a record that stood until 2010, when it was finally eclipsed by the Audi R15 TDI Plus.


THE MODEL
   
The eight photos that follow show various views of the FLYSLOT Porsche 917 LH #18 exterior. It is identical to the FLY Classic version of the car with a few exceptions, which will be noted further on in the review. The model deviates from the 1:1 car most notably in the nose area and in the shape and position of the headlights, as did its FLY Classic predecessor. This has been an issue for the CSE (critical scale enthusiast) in the past. Apart from those areas, scale accuracy seems reasonable, certainly good enough for me.


The FLY Classic version (shown inset in the above photo) has an additional Gulf logo on the inside of the tail fins, as did the 1:1 car. It also has the Firestone logo text on the tires and painted silver hubcap detail on the wheels.


One area of curiosity is the headlights. The black headlight housings are very similar to the FLY Classic cars, but unlike the FLY Classics, the FLYSLOT model does not have headlight lenses. I have seen photos of the FLYSLOT 917 LH on the Internet that do have headlight lenses and others that do not. The ones with lenses could have been promotional prior to actual product release. So, right now I'm not sure if this is a cost cutting measure or they were forgotten during product assembly. Note that the driver-side headlight assembly sits lower than the opposite one. This is because the two housings are attached to each end of a plastic "bar" that is, in turn, attached to the body. The driver-side end of the bar is bent downward slightly causing that housing to be lower. This is easily correctable.


Fit and finish, apart from the issues previously noted, are basically good. The paint and Tampo printing are quite good, with an excellent deep, clear finish with no noticeable sign of bleed through or ragged edges. There was flashing in just about every vent opening and along many body edges. This is most noticeable in the front view photo above. I have to say that this is a quality control issue, although it is completely correctable.

The interior is a shallow "half" tray type with minimal detail. The entire interior is black with the sole exception of the driver's head. This seems to be a more common approach now even in more expensive high-end slot cars. The prevailing justification for their use is to reduce weight in the name of performance, however, there is no doubt that they also reduce cost.
 

MECHANICAL
 
The following two photos show what is certainly the most significant difference between the FLYSLOT Alpha and FLY Classic cars: the chassis. The FLY Classics used a two-piece chassis which separated the side-winder drive train from the front axle and guide (I hesitate to call the rear half a pod). I for one was never able to discern any obvious benefit from this. The FLY Classics also used stub front axles, which usually exhibited significant off-axis play.

The FLYSLOT Alpha chassis is a simpler design with an in-line drive train. Gearing consists of a 9 tooth plastic pinion driving a 27 tooth crown. The front axle is now a single, solid type, spinning inside closed loop axle holders which allow several millimeters of vertical movement. The rear axle bushings are plastic. The bushings in this particular car were very tight. To the point where the axle was binding and did not spin freely. Rather than attempt to replace the bushings, I decided to lubricate them generously and allow them to break in. This seems to be working as the axle now spins much more freely. I wonder if this was a mistake in bushing selection or a clever approach to providing bushings with minimal play. Time will tell.


The motor leads are routed neatly and securely underneath the front axle through two thoughtfully placed guide loops terminating in what appears to be the standard guide assembly that FLY/FLYSLOT has used for years. Braids are the relatively stiff copper kind found on most mid-priced slot cars. The Mabuchi-type FC130 motor in bell-end drive configuration looks identical to the black end bell motor used in some past FLY models, however, lack of any external identification makes it impossible to tell with certainty.


A bar magnet that appears to be slightly weaker than that of the FLY Classic models is securely installed in a chamber just behind the motor. The magnet can be moved to another chamber in front of the motor in order to allow some drifting of the rear end. Or, a second magnet could also be installed in the forward chamber.

If I remember correctly, all my FLY Classics exhibited chassis warp to some degree. The chassis on this car is perfectly flat.

One characteristic of this chassis that may present an issue for some is the integrally molded spare tire at the rear (see above). The tire rests above the underside of the body's rear deck and actually makes contact with the body. This tends to preclude the ability to set the body to float — at least in the rear. I loosened the rear body screws as much as I dared and was able to obtain only minimal body float. As of now I don't know how much improvement in performance more body float would provide, especially in no-mag running.

The wheels appear round with minimal flashing and show no sign of wobble. The rear tires are round and true but one of the front tires has some minor shape issues. The tires could all benefit from some truing but that has not been an issue for me in the past because NINCO track tends to take care of that for me.


PERFORMANCE

First, the steps for basic N-Digital conversion and operation were performed:

- Instead of removing the magnet, it was moved to the forward magnet holder.

- Installed the Slot.it (CH26) Racing Guide (for me this is automatic for FLY Classics). The guide is a perfect fit. The braids are NINCO ProRace, tinned.


- Lubricated the guide post, front axle holders, rear axle bushings, motor bushings and gears.

- Installed an N-Digital decoder chip.

* In the following photo, the white arrow shows the N-Digital chip removed from the red case and protected by electrical tape. The red case would not fit in the limited space available inside the 917 LH body. The red arrow shows the "quick disconnect" plug system that I use to install most decoder chips.


After completing the above listed steps, I ran the car at low-to-medium speed with the rear tires raised off the track for about 20 minutes in oder to provide some initial break-in and to loosen the tight fit of the rear axle in the bushings. This seems to have worked well. Then I took the car straight to the track and ran some un-timed practice laps using the N-Digital system's professional throttle profile. After the first few laps my impression was that the car handled very well. The drive train is surprisingly smooth and quiet. Speed on the straights and handling in the corners are both good, allowing the car to stay in the slot even when driven hard.

Next, I removed the magnet. To my great surprise, this FLYSLOT Porsche 917 LH did something that none of my other FLY Classics were able to do under the same initial circumstances: it completed an entire lap without de-slotting. It actually completed a number of laps without de-slotting. In other words, this car ran quite well in the absence of the magnet with virtually no modifications other than the Slot.it guide. I have three FLY Classics that required modifications to the stub axles, addition of ballast and complete replacement of the drive train gears before they got to that point! There was also no evidence of fish-tailing which I thought might be a problem because of the 917 LH's pronounced tail section.

For the timed testing I ran the car in three different combinations of magnet configuration and N-Digital throttle profile: 1.) professional profile with the magnet in the rear; 2.) professional profile with the magnet in mid-chassis; 3.) amateur profile with the magnet removed. For those not familiar with N-Digital: the so called amateur throttle profile is roughly analogous to 9-10 volts maximum in analog with a mild response in the lower end of the throttle curve for an adjustable (PWM) electronic controller. The professional profile is closer to 11-12 volts maximum with a steeper response in the lower region of the curve. The car was run for about 100 laps in each combination

A lap time comparison for the various combinations is shown in the following table:



CONCLUSION


When it comes to appearance, the FLYSLOT Porsche 917 LH #18 is somewhat of an enigma. On balance, it is a good looking model. It retains the basic appearance of its now rare and expensive predecessor. But there are a number of quality issues and the reduction in detail, although acceptable to my eye, may be more than the CSE can tolerate. Regardless, all the issues that I was able to perceive are easily correctable with minimal modeling skills and resources.

Performance and handling, on the other hand, are surprisingly good. Definitely superior to the FLY Classics in stock condition. The new chassis and drive train seem to be an improved, cleaner, more efficient implementation. The lap times that I experienced indicate that this car, although not a rocket sled, runs really well over a wide range of magnet and track voltage setups — at least on NINCO track. This should allow it to be made competitive not only with the prior FLY Classics, but a significant range of existing slot cars of its era. I found the car to run exceptionally well with the magnet in the mid-chassis position and plan to run the car most often in that configuration.

So, if you like to run iconic race cars like the FLY classics, want reasonably good performance without a lot of added expense, but also want the potential to improve performance through tuning, then I recommend this car without reservation. And the price that you will have to pay will make it easy to justify.

__Michael Ashton

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