Aurora Model Motoring Thunderjet 500 Hop Up Hints- Aurora Plastics Corporation - West Hempstead, Long Island, New York (Front Cover)
Introduction - Success in racing, whether with real cars or with miniature electrical replicas, is dependents upon two basic factors... the ability of the driver and the speed of the car which he drives. Although there are so called natural drivers, it is generally agreed that almost anyone can improve their driving skill, to the point where they become more and more familiar with the winners circle, by constant practice. However, without a properly operating car, tuned and working as close to perfection as possible, even a Stirling Moss cant be expected to win races with any degree of consistency. Like their big brothers, the fleet of Aurora Model Motoring Thunderjet powered cars can be modified and worked on to increase their performance. This T-Jet Hop Up Kit will give you the basic ideas and equipment necessary to attain considerably faster speeds with your cars, but like the manuals for hopping up real cars, the ideas within the pages of this booklet are only the beginning. These ideas, plus your own additions, will be the factors that give you an edge on your competition. Well look for ou in the winners circle... Happy Model Motoring! (page 01)
HOP UP ACCESSORIES and TOOLS - Screw Driver, Tires, Brushes, Pick Up Shoes, Slicks, Wheel Axles, Crown Gear, 12 Tooth Gear, Speed Oil, Decals, Hubs (page 02)
PARTS BREAKDOWN - CHASSIS ASSEMBLY UNDERSIDE VIEW.
LUBRICATE MOTOR AS SHOWN WITH A SMALL DROP OF MODEL MOTORING SPECIAL RACING OIL EVERY 3 OR 4 HOURS OF OPERATION OR SOONER IF CAR BEGINS TO SQUEAK OR SLOW DOWN.
IF MODEL MOTORING SPECIAL RACING OIL IS NOT AVAILABLE USE A LIGHT MACHING OIL OR MOTOR OIL AND APPLY WITH TOOTHPICK. HOWEVER, SUBSTITUTE OILS MAY REDUCE TOP SPEED AND REQUIRE MORE FREQUENT LUBRICATION. (page 03)
PARTS BREAKDOWN - MOTOR ASSEMBLY TOP VIEW
CAUTION: THIS IS A DIRECT CURRENT MOTOR AND IS DESIGNED TO OPERATE FROM D.C. POWER PACKS (A.C. TRANSFORMER WITH BUILT IN A.C. TO D.C. CONVERTER) OF 12 TO 20 VOLTS D.C. - WARNING: DO NOT ATTEMPT TO OPERATE WITH STRAIGHT A.C. TRANSFORMER, OTHERWISE BURN OUT WILL RESULT. FOR BEST OPERATION USE AURORAS MODEL DC-2 20 VOLT D.C. POWER PACK. (page 04)
Wheels - Since Model Motoring cars resemble real cars many of the same factors come into play in increasing speed. The diameter of the wheels, for example, have an important effect on the speed of any vehicle, and your Model Motoring cars are no exception.
Lets assume that the RPM (revolutions per minute) of an axle stays the same no matter what size wheel and tires are placed on it. If this is the case, then the larger the diameter (the distance around the outside) of the tire, the more distance the car will cover in a given period of time. Actually, this is not entirely correct for wheels and tires can be obtained that are so large they have the effect of slowing down the RPM and, in turn, slowing the car.
But in the case of T-Jet Model Motoring gears, speed can be increased by mounting larger tires and wheels (A). Take off the car body and replace the car hubs with T-Jet Racer Hubs(B) and the car tires with either T-Jet Racer Tires or Slicks. To run the car without its top and keep the Guide Pin in place at the same time, simply use one of the old car hubs, place it above the Guide Pin Hole, and turn the Guide Pin Screw up tight into the hub. In order to remount the car body it will be necessary to cut out wheel wells (C) to clear the larger tires.
To go one step further, obtain a set of axle, hubs and slicks fo the new 1/4 inch Super Model Motoring cars and mount those on your HO scale vehicle. Aside from the wild raked look, some driers report an impressive change in speed. (page 05)
Tires - With three kinds of tires already being produced for your T-Jet vehicle (car, racer & slick), you shouldnt have much trouble in finding the proper combination for your particular needs. Just remember that drag racing may not call for the same type of rubber as a sports car course. In general, slicks are proving the best all around type of tires since the maximum amount of rubber is on the track surface. Drag racers like slicks for the increasing traction at the starting line (where too little rubber permits the wheels to spin) (D) and road course drivers are finding that the extra rubber on the slicks cuts down on the tendency of their cars to drift and slide through the turns.
Make sure that there is no friction where the rubber of the tire rubs against the inside of the fenders (E) on the car. If this situation aexists, trim away the plastic with a sharp blade to remedy the problem.
Fast speeds are impossible if your tires are out of round (high and low spots). The best way to clear this up is to connect two wires from your power pack to the Pick Up Shoes and let the rear wheels spin freely. An application of sandpaper (F), with care, to the road surface of the tire will grind off the highs and bring your tire back into the round.
It is very important, no matter which tire you use on your drive wheels, to clean them off between each race. Although it may seem unlikely, some drivers rub oil into their tires which has the effect of rotting them slightly, making them softer on the surface of the roadway and increasing traction. If the tire is impregnated with oil, a water detergent solution will be necessary to rid the tire of any dust particles before a race... since water (by itself) and oil do not mix. Remember, more than one race has been won by a car jumping into an early lead because it had maximum traction through the first few laps while other cars were sliding through the turns because of dust particles on their tires. (page 06)
Gears - Just as with the rear end on a real car, changing the gears in a T-Jet powered vehicle is of prime importance when seeking an increase in speed. Enclosed in your Hop Up Kit is a 12T12 tooth drive gear with shaft and a short boss crown gear. Using great care, remove the Gear Plate and Armature assembly from your car. The short boss crown gear goes into place by pulling out the rear axle assembly and removing the long boss crown gear that comes with your car from the factory (H). Under the Gear Plate Armature Assembly is a small 9 tooth gear called the Drive Pinion Gear(G). Replace this 9 tooth gear with the 12 tooth drive gear in the Hop Up Kit and reassemble the car.
After running your T-Jet with the new gear ratio you may find that the car is too hot for you to handle on a road course. If this is the case, reverse the process and install the original factory supplied gears (I).
NOTE: We do not adise removing gears from these shafts more than twice since the hole in the gears will become enlarged and will no longer grip the shaft. (page 07)
Motor - Did you ever go to a real race track where the mechanics in the pit area never seem to be satisfied with the tuning of a motor until they are forced to let it go out on the track? Again, here is a parallel between real cars and T-Jet powered vehiclesm for to attain top performance in either requires constant adjusting of the motor.
For example the pressure (J) of the brushes on the surface of the commutator is all important. In some cases the pressure of the brush spring should be relieved as the brushes are too tight, but generally, it is worth trying to increase the commutator brush spring pressure to force the brushes tighter against the surface of the commutator.
Since any electric motor needs all the air it can get to prevent overheating, it is a good idea to drill one (K) hole on each side of the slot car chassis in the immediate area of the motor to increase air circulation. This has the additional value of permitting the dust from the brushes to escape instead of flaking over the surface of the commutator and building up a deposit. In addition, it helps to lighten the weight of the frame making the power of the motor more effective.
A WORD OF CAUTION: Be sure to replace magnets in original locations otherwise your car will run in reverse, a sure way to lose a race (L). (page 08)
ADDITIONAL HINTS - Friction is the bug-a-boo of every race car. The oil supplied in your Hop Up Kit has been specially compounded for T-Jet powered Model Motoring cars. Use it in the locations indicated on pages 3 & 4 of your Hop Up book as well as on the axles (M) here they pass through the frame of the vehicle. The junction of the Crown Gear and the Drive Pinion Gear deserves occasional attention with oil as do all of the shafts that pass through the Gera Plate. Some drivers evenoil their Guide Pins to reduce friction before an important race.
CAUTION: Over oiling will foul up commutator brushes and neccessitate cleaning. If a soldering iron is available try soldering a fine wire... between the Pick Up Shoe Holders and the Pick Up Shoes(N). This simple connection is certain to increase electrical conductivity and continuity which will result in better and smoother performance. Pick Up Shoes are included in the Hop Up Kit for this purpose.
Experimenting with additional weight, particularly over the rear axles and wheels (O) is a further way to increase the traction and cornering ability of your car. However, there is a point of no return in adding weight, a point where the more weight you add will decrease the acceleration and handling ability of your car. Watch for it. Too much weight is harder to overcome in a racing situation than too little weight.
Although racing rules limit the voltage for T-Jet powered cars in HO scale to 24 volts, up to 30 volts may be used in races of short duration or on drag strips. Naturally, higher voltage will increase performance and speed without any additional modifications. (page 09)
ADDITIONAL HINTS (CONTINUED) - No matter what you plan on doing to hop up your T-Jet powered vehicle, stock up on parts first. There is nothing more frustrating than to find yourself in the middle of a reworking job and then find that your hobby dealer is cleaned out of the parts you need. Buy the spare parts first (as do the mechanics who work on real race cars) and then go to work on your bomb.
As we mentioned at the beginning of this booklet of Hop Up Hints, we hope these suggestions will speed up your trip to the winners circle... Happy Model Motoring!
For the technically minded racing fan, put an Electrolitic Capacitor (500 MFD, 24 volts DC) across your power pack terminals (positive to positive, etc) which will smooth out your DC power and make your cars run more efficiently. (page 10)
NEW SERVICE PARTS LIST FOR MODEL MOTORING CARS AND TRUCKS THUNDERJET 500 MOTOR (Back Cover)