'Doba's thread on the possibility of replacing 440/440X2 magnets with weights had some interesting discussion. I'd like to expand on that a bit with the results of testing (which is really just a fancy way to say "playing") that I've been doing.

I find it hard not to get excited about the G-Jet, P-Jet, etc., but I'll admit that I'm not too keen on dropping $50 each for these cars. If I were racing, it would be one thing, but the truth is that I'm just playing around at home, and these cars will probably never make it out of my basement. So the obvious question is: can you get a similar effect just by modifying readily available cars? A poor man's G-Jet, if you will...

All tests are run on my 26' 4x8 road course. I don't have a timer yet, so there is no hard data. Instead, all of my feedback is based on how the cars feel. That's OK though, because the point of this thread is not to tune a car to its absolute fastest condition. Rather, the point is simply to give basement racers ideas for new ways to play with cars that they already own.

I'm looking for performance in that magic range somewhere between t-jet and full magnet car. Specifically, I want a car that can drift a bit without being a tail-wagger...a bit looser than a G+, but not as loose as a Magnatraction.

I started by yanking the traction magnets out of a (very old) 440x2 narrow chassis and slapped on a stock car body. Then I dialed down to 12V and started having fun. Here are the results:

Stock Tires (.465): Power comes on strong. Too strong. A lot of wheelspin under acceleration. Surprisingly, there’s not a lot of fishtailing, but if the rear end does step out, it’s very hard to bring it back in line. If you fishtail, you’re probably going to spin. It’s a bit precarious…like driving on ice. Impossible to get a good, controlled drift. Pace reminds me of a stock t-jet.

Silicon Tires (.450 AJ’s Gum Drops): Takes off like a rocket (er, relatively speaking!). Much faster down the main straight The difference in speed is like moving from a t-jet to a G+ or a fast MT. It tracks true and I still can’t get a controllable drift. However, now when the rear end comes out, it just scrubs off speed and then comes back in line. It doesn’t keep going around like the stock-tired car. Fairly forgiving, but it doesn’t like to be pushed. Best description is probably “twitchy”. I’m certain that a lap timer would show better times when you slow down and focus on being smooth. Pushing it too hard just slows you down. In other words, drive slow to go fast. Interestingly, it gets easier to drive – more progressive – as the tires get dirty…although it’s also slower. Still drivable on 15V and 18V, but would require a <60 ohm controller.

Silicon Sponge Tires (.448 Wizard Law Black): Much more responsive. Less twitchy and more forgiving than with sillies. Handles well right up to the limit. Possible to repeatably and predictable kick the tail out in some corners, but can’t really maintain a smooth drift. 18V is just not an option with a 60 ohm controller. Higher ohmage may help, or it might be that the power from the motor simply comes on too strong. It’s interesting to note that the power curve is way more aggressive than the stock Tyco. Removing the traction magnets takes away a lot of rolling resistance. Where the stock car could be driven very slowly around the track, the mag-less car can not. This phenomenon only gets worse as you upgrade the tires – although at least the stickier tires eliminate the dreaded spin-inducing wheelspin. It would be interesting to try the car with a slower arm – maybe from an HP7…

I also tried the silicon-sponge-shod car with a Ferrari F1 body, and I was pleasantly surprised. Performance is actually very realistic. It tracks true without fishtailing until you get a bit too aggressive. Then the rear end kicks out, but it gives you a chance to save it before you spin.

OK, I just had a “duh!” moment. I thought I could tame the mag-less 440 by replacing its arm with the arm from an HP7 can. I was hoping to slow it down enough to drive it with a full 18V of power. Unfortunately, I didn’t realize that they are completely incompatible. The 440 brushes are in the same plane as the magnets, while the HP7 brushes at rotated by 90 degrees. That means the HP7 commutator is also rotated by 90 degrees…explaining why I was barely able to get the arm to turn over when it was installed into the 440 chassis. Oh well, lessons learned, eh?

Tomy Turbo and SG+ reports to follow…eventually…

Take a look here I have done the tests on 26' track with a timer

http://www.hobbytalk.com/bbs1/showthread.php?t=210220

Conclusion: attempted control by weights, is marginal improvement for Tomy Turbos and G+
Its very real for all tjets and dramatic for many of them

Voltage regulation or a resistor in series (ie current regulation) helps you control the cars without the mags

I tried a G+ arm in a no-mag Tyco today. I've been running the mag-less Tycos at 12 V and having a blast. But I'd really like to be able to run them at the standard 18 V so they can race against other cars in my stable. I was hoping that the G+ arm would tone the car down enough to run at 18 V. It helped a bit, but it was still waaaay too punchy. I'm looking for an arm that would have similar performance to an HP-7, and it needs to have a com that's set up for brushes parallel to the magnets. I'd like to try the arm from a TycoPro/Curvehugger/HP2, but the shaft is way too short. Any ideas???

Wildstar --

I think that you will find that you will want to turn down the voltage for inline non-mag cars. When you take the magnets out of an inline chassis, you are taking a lot of the load (magnetic drag) off the motor, effectively making the non-mag car significantly more powerful at a given voltage. The addition of weights to the car helps tone this down a bit, but the weights put less load on the motor than the magnets do.

A de-tuned motor is an alternative to running at a lower voltage, but probably the cost of new arms will end costing a lot more in the long run than springing for a cheap adjustable power supply, like the $28 one from Scale Auto.

The 1/32 scale racers also turn down the voltage when they take the magnets out of their cars. Typically they do not change the motors, although that theoretically is an option.

You could wire your track so that each lane could have their own variable voltage if you wanted to run dissimilar cars together.

-- Bill

When you take the magnets out of an inline chassis, you are taking a lot of the load (magnetic drag) off the motor, effectively making the non-mag car significantly more powerful at a given voltage. The addition of weights to the car helps tone this down a bit, but the weights put less load on the motor than the magnets do.

That's for sure! With the traction magnets, I could creep along at a walking pace. Now, without the extra drag from the traction magnets, the power comes on a lot stronger, even at 12V. I'm still hopeful that I find an arm that is mild enough to let me run these cars on 18V, even if I have to learn how to wind my own arms.

Wildstar you're missing part of the equation, the TycoPro/Curvehugger/HP7 all had much weaker motor mags, if you did get those arms into a 440, you won't see much difference, especially at 18V. To copy myself from a recent post on another board:

A few years back I had a small supply of 12-ohm arms that were a drop-in for Tycos, thought I'd make a car for my then 4 year old daughter. While initial punch was softened a hair, once the car was rolling it pretty much ran like a stock car, lap times were only lower by tenths. On a short track it will feel virtually unchanged. The biggest part of the mystical G-Jet/9-ohm arm driveabilty equation that lately seems to be forgotten is that they are running on 12 volts.

Hmmmm...you raise an interesting point, swamper. I hadn't realized that there was so much difference in magnet strength of 440 vs. HP7. About those 12 ohm arms...do you still have any of them? If so, would you be willing to pop one into a 440 without traction magnets to confirm the theory?

I'll have to dig around, if I can find one I'll try it. That was a couple years ago so :freak:

Here's a link to see the brass weights for a Tyco 440x2:

http://users.cescowildblue.com/jwsteed/newpage2/MM01.jpg

The armature you want is blue.It comes in the Tyco Extreme
racers with the trapped guide pins on both ends of the 440
chassis.

Are the brass weights pictured in this thread available for purchase?

Where, how much, etc. ??

Jim says the brass weights are on the Tyco parts page. Give him a holler, he'll point 'em out for you.

I have a couple of G JETS and did a comparison between it and an X2 and and a MT.

On my small track a G-JET zips around till it deslots very seldom does it fish tail. Torn it upside down on a 6 inch staright and you have to tap the track for it to fall of.

Take an X2 totally stock pan chassis on my track onl ya couple hundreds difference in times but will slide more. (Note this is on 12 vdc) The G-Jet is faster down the straight but both are equal in the turns. Also Note Chassis only no Body Upside down on a 6 inch straight with a G Jet both fall off with a tap together.


Stock XT/MT no chance several tenths difference in times and does slide quite a bit. Upside down falls off. Put a set of Polymer magnets in XT still stock all around stays with the G-Jet and XT. Upside down on a 6 inch straight all 3 cars stick and fall off with a tap.

Now on a big track the G-Jet going to eat everyone alive at 12 Volts. Maybe if you get an armature from the HotWheels Battery sets that use X2's You can get it to stay with a G-Jet on the longer straights. Alss drop a good mean green in the XT with the Polymers and it should get closer.

You will notice that both the X2 needed the traction magnets and the XT needed the Polymers to have the same down force as the G-JET.

Roger Corrie

Good input there, Roger. Just to make sure I understand correctly -- are you saying that a G-Jet and stock Tyco (WITH magnets) have similar handling at 12V?...except that the Tyco slides MORE??!! I've never driven a G-Jet myself (one of these days, I'll join the 21st century:p), but I was under the impression that they drifted a bit more than your typical modern box stock car. Is this not the case???

The armature you want is blue.It comes in the Tyco Extreme
racers with the trapped guide pins on both ends of the 440
chassis.
Thanks tjettim. Any idea where these arms can be found? I did some searching today and found Tyco Extremes cars at Lucky Bob's, but nobody seems to be selling just the arms -- and I really don't want to pay $20 for a car that I don't like just to get an arm:freak:

Could someone please post a link to the webpage for the Tyco Jet weights?

I don't know who the "Jim" is that you are referring.

http://users.cescowildblue.com/jwsteed/newpage2/mprod.htm

The Tyco weights are about 1/3 of the way down the page. Anybody try these out yet?

The arms are 13 ohms but I haver never found a source
except the whole car.But since it is an X2, it is a good
source for spare parts.I found on 12 volts the lap times
were very close between a G-jet and a 100% stock
X2 indy car.If you lower the Tyco at all it will be too easy
to drive.The lifelike T-chassis cars are too stuck for
12 volts but the M-car isn't bad 100% stock.The Micro-
Scalextric cars are designed for 12 volts and also are
fun right out of the box. I get mine from Ebay sellers
in England.Realistic speeds and realistic bodies add to
the fun.If the tires weren't all dried out I would get
my Riggen out of the showcase and try it on 12 volts.

Good input there, Roger. Just to make sure I understand correctly -- are you saying that a G-Jet and stock Tyco (WITH magnets) have similar handling at 12V?...except that the Tyco slides MORE??!! I've never driven a G-Jet myself (one of these days, I'll join the 21st century:p), but I was under the impression that they drifted a bit more than your typical modern box stock car. Is this not the case???

Yes its true they handle very similar. The new X2 in the Speed Racer set are Battery operated. I tried them on my track and they have some more straight away speed but the wheel/tires are so out of round I could not get as good a lap times. When my mail in race is done I plan on doing some testing of the battery operated X2's vs the G Jets.

Roger Corrie