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| Review - G-Jet - New offering from BSRT |
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| By Steve Medanic |
The BSRT G-Jet is the newest variation of the G3 chassis. The G-Jet is designed to make racing more fun and more attractive for the racers. It also designed as an entry vehicle to the hobby as the car is easier for the novice to drive as compared to club stock, super stock or any of the other faster “magnet” car classes. In this racers opinion the G-Jet is what a full tilt Fray style Thunderjet wants to be.
G-Jet Action in the Pro Main at the 2006 Western States
The changes from a standard G3 car with a flexible chassis to a G-Jet rolling chassis (roller) are as follows. Spec front o-ring and rear AST (silicone/sponge) tires. The rules require black rear tires which brings back realism as compared to white, red, green or orange tires. The rear tires are not just black but use a special compound and coating that was designed specifically for the G-Jet. The car comes with a 9-ohm arm as opposed to the G3's 5.8-ohm motor. Like the tires, the motor was specially designed for the G-Jet. Its not a mass produced toy motor but the wire size and windings were specifically selected to maximize performance. Plastic body posts are preinstalled. The posts have been reworked to eliminate problems associated with earlier versions. The rear traction magnets are replaced by brass weights and a nose weight is fitted in the space between the front bumper and the guide pin. This weight is secured to a second weight that sits above the chassis and occupies the space between the pickups and the front axle. As a result of the front weight the G-Jet is a short wheelbase car. Like the tires and motor the pickups and pickup holders were designed specifically for the G-Jet. The G-Jet wasn't a one day wonder. A lot of time and effort was put into the design of the car to get it "just right". The G-Jet roller is built in house by Scale Auto and features a tweaked setup that has been track tested by Gary himself. Any car that doesn’t make the cut is torn down and inspected to determine what went wrong and identify if changes are necessary to ensure it doesn’t happen again.
The following photo shows the chassis of one of my two cars as it was raced at the 2006 HOPAC Western States race. The red on the brass “traction magnets” is not stock but is just red marker that was added to detect if the car is rubbing on the rail. The "brass" pickups.are really a bronze alloy that is
My first experience with the car was at the 2006 HOPAC Western States race. The Western States race is not so much an end of season race but the end of season Party for the HOPAC tour. This race has to be experienced to be believed as the race is secondary to the camaraderie and fun. There is no hidden addenda or politics at this race and help, setup tips, parts and cars are available from everybody for the asking. The level of competition is fierce and making the main is as tough or tougher than making the main at the various national championship races. The HOPAC tour ran the G-Jet during the 2006 season as part of the cars development process. The car as raced at the Western States was very close to the final configuration. It's my understanding that minor updates, designed to further improve the cars performance, will be incorporated before the car is officially released.
I really didn't have much time on the cart when I got to the race. I was sent a motor and a weight kit about a week or so before the race and built the chassis that is sitting under the Chaparral 2D out of available parts. The weight kit has heavy and light weights. I quickly settled on the light weights and a 7/22 gear ratio. The first runs were with white AST tires. I immediately ordered some "G-Jet tires". After fitting the black tires I hit the track for a final test session. After a few laps I just started laughing as the car was just so much fun to drive! Its my understanding that I am not the only one to have that reaction. After those initial laps it was time to pack and get on the plane to Seattle.
At the Western States there were two tracks that we ran the G-jet on. They were a Bucktrack Riverside with a painted wood surface and an original Aurora Tub track with a new four lane Brystal plastic insert. The cars could go from track to track with no change in setup or performance. A good lap time was 3.5 seconds on the Bucktrack Riverside and 4.0 on the Tub. First Scale Auto’s Dean "The Machine" Tweeddale showed me what they do to make the rolling chassis and then what he would do to make a race car out of a roller. The changes are minor and easy to do. After tweaking the home built car up to a competitive speed I decided to add a second car to the stable and picked up a G-Jet roller at the factory. This was not a hand picked car but a plain, out of the box, G-Jet rolling chassis. The car was immediately on the pace. Two days later that same car made the top eight in the Pro G-jet race having won two consolidation races to make the B-semi. With a bit more time the car could have made the main. Those with more experience were faster but the field was relatively flat and about half a second covered the 20 person pro G-jet field. The car is quite responsive to changes in tire height, pickups, springs and gearing. The rolling chassis comes stock with 7/22 tooth gears and the lighter weights. Most ran the lighter weights and a 20 or 21 tooth crown gear but the stock 22 tooth crown didn’t do bad at all. Compared to the other cars the 7/22 tooth car accelerated out of corners better and I was able to brake later. Top speed wasn’t an issue with the 22 tooth crown. My problems were a result of lack of seat time as opposed to problems with the cars design or execution.
The car races very well. Side by side racing is the norm and the fine art of nerfing is alive and well! As with T-jets you have to plan your pass as the guy on the inside can take you out if you are not careful. However, unlike T-jets, which when prepared to the Fray rules are open wheel cars, the G-jets are full width enclosed wheel cars and you can lean on and trade paint with the guy next to you! The top photo was taken immediately after a pass in the esses. A move like that with an open wheel car would most likely have ended in disaster. There were many cases where side by side battles went on for 10-20 laps or more. I recall a segment long battle where no more than a few feet separated the cars at any one time. In the G-Jet Pro main Andre Perra went wire to wire to take the win. In keeping with the R&D spirit of the HOPAC tour and the race, Andre is sending the winning car back to the "factory" so it can be evaluated and see if the base car's performance can be further enhanced. Is this good or what!
Does the G-Jet work as an entry level car? Let me offer the following as an answer. One of Gary ’s neighbors sons showed up on Friday to see what was up. One of the racers spent a few minutes discussing the event with him and then handed him a G-Jet car and controller. After a minute or so of instruction he was turning laps on the Tub. I don’t think he ever put the car on the floor as he started slow and mostly spun out when he hit the limit. As a result of the cars good manners, he had the hang of the car in less than 30 minutes. Within a few hours he was running with the best and not leaving much on the table. He ended up running that car all night! He really wanted to come back and probably will.
The “speed-crazed” may find the car a bit slow but for the rest it’s a perfect, fun to drive, fun to race car. I have been racing T-jets (Aurora Thunderjet 500 cars) in various forms since 2001 and in my opinion the G-Jet is what a full tilt Thunderjet built to the Fray rules wants to be. At the limit they drive much the same but there is where the similarities end. The T-Jet is a 40-year old design whose driveline features one plastic and two metal vertical shafts, a horizontal shaft, four poorly made brass gears and one poorly made plastic crown gear. They haven’t been made since the late 1960s or early 70s and per my sources parts are running out. The G-jet is a modern design with two horizontal shafts and two well made plastic gears. Building competitive Fray, NITRO or Super Stock Thunderjet requires a considerable tribal knowledge database, advanced building skills, specialized parts and can take hours per car using parts and tools are not that readily available. Quite a bit of parts sorting is the norm to get a good car. A competitive G-Jet can be yours with a few minutes of work and requires no special skill or parts. With the exception of the brass weights and armature any part built for a Super G+ or G3 chassis can be used on the G-Jet. The parts unique to the G-Jet are a phone call away as are building and setup tips.
The Thunderjet runs on 18 VDC and requires a fair bit of maintenance to keep it running at its finest. Rebuilds and tweaking sessions between races are the norm. The G-Jet runs on 12 VDC and the arm, brushes and pickups seem to last forever. There was little tire wear and no gear or bushing wear after three and a half days of racing. The car was packed up immediately after the race, sat in a suitcase for about 30 hours and survived the long plane ride back to Chicago as checked luggage. When placed on the track at home the car ran fine and didn’t require any maintenance. I'm convinced that, if sent back to Seattle, they would be as fast now as they were then. Scale Auto’s Gary Beedle and Dean Tweeddale indicated that my experience is typical. They recommend breaking in an arm and motor brushes (a.k.a. endbell) for 24-hours on 3-4 Volts. Other speed tweaks involve the usual endbell electrical system tweaks, reaming the arm bushings with a 0.062” reamer and chamfering the side of the bushings away from the magnets. The side of the bushing facing the magnets is polished to minimize friction. The front axle holes are reamed with a 0.052” reamer. It is critical that the front axle holes are reamed only after the front weight is installed. The roller arrives with stock bushings that have been reamed to 0.061” and the axle holes reamed to 0.051”. The endbell electrical system has been pretweaked as part of the factory build process. Each rolling chassis is track tested by Gary before packaging. If the car doesn't cut it, it doesn't get sold. From my experience I tend to believe that there is no such thing as a bad rolling chassis, The car really responds to reducing friction and weight. As the above chassis photo shows getting the pickups just right doesn't hurt either. The pickups on that car ran for four days and have a good contact patch and very light wear.
Performance is excellent. The car runs in the middle of the gap between superstock and Fray style T-Jets. After the race, the G-Jet I raced at the Western States turned 4.3-4.4 second laps here at CRR in Red. Red is the long way around and about 0.1 second/lap slower than the center lanes. With work a very low four second lap is attainable. A four second lap is midway between the best Fray style T-jet lap ever and a good superstock time. Not too fast and not too slow either.
To date there have been several six and nine hour endurance races for the G-Jet with no changes or maintenance with the exception of oil. Because of the lower speeds the bodies don’t get beat up and can be used for a season or more. This, plus the requirement for black tires, encourages the painting of good looking race cars which is another plus. Some of the cars at the race were simply gorgeous and were driven hard as the risk of crash damage was low. After the races the cars looked as good as before. Scale Auto plans a series of detailed premounted Lexan bodies for the G-Jet. What may be a prototype of a typical body appears in the following photo.
