This Q&A section has general information pertaining to the XMOD Gen1 cars. There are several Q&A sections and you will find an index of them at Q&A Central.

If we get the same question twice we add it to the Q&A, so most questions have already been answered. So please check the Q&A first. If you don't find your answer in the Q&A, then by all means, drop us a line.

The Ion Pro 2S Pack performs better because it has a direct connection soldered to the board and it is lighter. The Ion Pro 2S Pack fits under the bodies better on all of the cars. The ability to change batteries is moot because you will need you to allow the car time to cool between packs anyway. The biggest difference is in the installation difficulty. Look over the Ion Pro 2S Pack Installation Tutorial and if you are comfortable, then buy the Ion Pro 2S Pack, if not, the Quick Kit is for you.

In the old days, we had no way to measure it, but now that we have invested in some lab grade test equipment we can tell you exactly what the difference is. On the chart below we plotted the comparison between the Ion Pro 2S Pack and the Quick Kit.

The Test:
With our Computerized Batter Analyzer, we can apply any amperage load we wish and plot the result. Both Kits were charged up to 8.4 volts on our Orbit Microlader. I applied a 1 amp load for the test. As the load is applied, the voltage drops immediately on both packs. On the Quick Kit it drops more and the Quick Kit supplies less voltage throughout the power curve. This accounts for it lasting 20 mAh longer. The more power you draw from a cell, the less of its rated current it will deliver before hitting the safe cutoff voltage. I pushed the cells slightly past 6 volts which is fine here as I am controlling the test closely.

Conclusion:
The results of this test tell me what I had suspected but, until recently, had no way to measure, there is a lot of energy lost on the springs and extra contacts that make up the Quick Kit.

That is a matter of opinion, I personally think it is quite simple, but others may not. Take a look at the Ion Pro 2S Pack Installation Tutorial and if you are uncomfortable with the procedure, go with the XMOD Gen1 Lithium Quick Kit.

1. Lithium Power System - Ion Pro 2S Pack
2. XMOD Gen1 No Drill Board Harness*
3. 500 mAh Lithium Ion, Lithium Poly Auto Charger**
4. Power Adapter - 12V AC-DC***

*The No Drill Board Harness is optional, but if you are uncomfortable drilling, get it.
**Any of the chargers will work, the AC500 provides the most bang for the buck.
***All of the chargers require a 12 volt power source like a power supply or a car battery. You can use your own, but if you don't have one already, the power adaptor is required.

The trick is to use a small hobby drill, and you can buy these at almost any hobby shop. The drill bit I use is a 1/16 or .062 diameter. Just take your time, its really easy.

Sure do it all the time, see the Labor section for info on this service.

This is very common, the problem is likely this: If you look closely on the top side you will see a pear shaped area that encircles the hold for the battery negative. I like to scrape this area to expose a larger surface to solder to. This ground wire must be soldered on the top and bottom of the board.

You didn't do anything wrong, but about 1 in 25 boards will exhibit this problem when you push the voltage and current beyond the intended limits. It requires a board replacement to get around the problem. If you go back to the factory cells the car will work fine again.

The Ion Pro 2S Pack performs better because it has a direct connection soldered to the board and it is lighter. The Ion Pro 2S Pack fits under the bodies better on all of the cars. The ability to change batteries is moot because you will need you to allow the car time to cool between packs anyway. The biggest difference is in the installation difficulty. Look over the Ion Pro 2S Pack Installation Tutorial and if you are comfortable, then buy the Ion Pro 2S Pack, if not, the Quick Kit is for you.

In the old days, we had no way to measure it, but now that we have invested in some lab grade test equipment we can tell you exactly what the difference is. On the chart below we plotted the comparison between the Ion Pro 2S Pack and the Quick Kit.

The Test:
With our Computerized Batter Analyzer, we can apply any amperage load we wish and plot the result. Both Kits were charged up to 8.4 volts on our Orbit Microlader. I applied a 1 amp load for the test. As the load is applied, the voltage drops immediately on both packs. On the Quick Kit it drops more and the Quick Kit supplies less voltage throughout the power curve. This accounts for it lasting 20 mAh longer. The more power you draw from a cell, the less of its rated current it will deliver before hitting the safe cutoff voltage. I pushed the cells slightly past 6 volts which is fine here as I am controlling the test closely.

Conclusion:
The results of this test tell me what I had suspected but, until recently, had no way to measure, there is a lot of energy lost on the springs and extra contacts that make up the Quick Kit.

(Yes this question was repeated on purpose)

Yes, the Lithium Quick Kit is designed to be a 5 minute install. It requires no special tools or skills. Anyone can do it, and don't ask me to do it for you. I would feel guilty taking your money.

1. XMOD Gen1 Lithium Quick Kit
2. AA Charging Pocket*
3. 500 mAh Lithium Ion, Lithium Poly Auto Charger**
4. Power Adapter - 12V AC-DC***

* When using a Quick kit, the charging pocket is required to connect the charger to the cells for charging.
**Any of the chargers will work, the AC500 provides the most bang for the buck.
***All of the chargers require a 12 volt power source like a power supply or a car battery. You can use your own, but if you don't have one already, the adaptor is required.

Take a look at the car specific details here in the FAQ to see which cars it fits.

No the XMOD will handle 8.4 volts just fine. Rob has cars that have had Lithium for two years that still run great. We also have countless customers are using Lithium without any problems. See the Customer Testimonials section if you don't want to take our word for it.

Yes, the lights will be a bit brighter, but they work fine.

No it isn't for a lot of reasons. They are the same voltage as AAA which is 1.2 for rechargeable cells and 1.5 for Alkaline cells. The only thing they have on the AAA cells is higher mAH ratings which means more run time. The real trouble is that they are bigger and heavier than AA so you can only fit two inside most of the bodies. 2 cells would only be 3 volts which won't work and if you managed to fit 4 you would have the same operating voltage you had with your AAA with a dramatic increase in weight. Bottom line is this: Your buddy with stock cells would smoke you....

No, 6 x 1.2 = 7.2 volts, this is well below the 8.4 maximum voltage limit. Bear in mind you are adding a lot of weight, Lithium will give you more current, more voltage and half the weight.

Well, that's a good question. They don't fit very well on most of the cars. The Honda Civic is the best car for this mod as it has a lot of room in the roof. You do have to cut the lighting system board mounts out of the roof.

Its really quite simple, you just wire all of the batteries in series. Think of a battery conga line. Take a look at the XMOD Generation 1 - 6 Cell Upgrade.

A Lithium car will stomp a 6 cell car due to the decreased weight and the lower internal resistance of the lithium cells giving the Lithium cells more punch. The lithium cells also have 3-4 times the run time. 6 Cell cars are top heavy and handle poorly, the Lithium cars have a lower center of gravity than even a stock car so they handle superbly and accelerate much faster.

No, 18-650 cells are way too big for an XMOD, but they are cheap because they are very common and used in a lot of products.

The Li670 Cells are .6" x 2.2" (15mm x 55mm) and they just barely fit.

No, it is above the 8.4 volt maximum safe voltage, and even if it would work, you would only get 2-3 minutes run time.

Not required, but recommended. The speed of a Lithium car will wear out the plastic bushings in no time.

A 2WD (2 Wheel Drive) requires 12, and an AWD (All wheel Drive) requires 14.

There are 6 locations in a 2WD car. The first 4 locations are the front wheel axles, the last 2 are the outer rear wheel axles. In an AWD car, use them on the 4 outer wheel axles only.

Yes, the only difference between 2WD and AWD is the addition of the 2 bearings to support the front axle cup shaft. These bearings are standard sized 2mm wide bearings and are included in the kit.

The wide track bearings cause binding in some AWD cars, if you have AWD, use the wide track in the 4 outside axle locations (next the wheels) and use standard 2mm bearings everywhere else.

I believe they are superior, I am buying them from a premium bearing manufacturer and the quality is outstanding. I have no method of measuring the rolling resistance, but they seem to be similar in that respect.

The Factory Cup Joint Shafts need to be filed down so they slip into the bearings with no effort. The short ones always fit fine, but the Med (front) and Long (rear) shaft will require the plastic portion to be filed. As you slide the shaft through the bearing you will see where it begins to bind.

Yes, you can place an order and we will hold it as a backorder and fill it when we receive them.

In most cases they are not, in a few they are. The real advantage is the precision and strength of these parts.

I will have only silver from now on because it cuts time off of the production cycle.

Yes, that is normal. The small tab that contacts the Servo output shaft is a bit too thick and must be filed down to clear the AWD differential gear. I have reported this to the vendor and they promise to fix it but have not committed to a time frame so far. You must file the front side of it to allow the AWD differential to clear it.

Take a look at the Antenna Isolation Tutorial. Please note, if you skip this step and mount directly to the deck it will work, but your range will be shorter.

The prices are all posted so what you see is what you get. You may think that if you spend a lot you should get a discount, but everybody else spends a lot too and we factor that into the pricing model.

Ion Pro 2S Pack: Very Snug	Drive Shaft: Long	Weight: 38.76 Grams
Quick Kit: No	Tires: Thick Wall

1. 350z Body
2. 350z Front Body Mount
3. Long Drive Shaft
4. 350z/Skyline Wheel and Tire Set

Yes it uses the same wheels as the Skyline. So if you have this car, you can keep your wheels. Note this car uses the thick wall tires. All of these parts are sold in the XMOD Generation 1 section.

The Quick Kit will not fit these cars at all, and the Ion Pro 2S Pack is a very tight fit. The car pictured has a Ion Pro 2S Pack and you can see the sides are bowed outwards a bit. This causes the rear wheel wells to pull in and rub the tires. A nice body, but not great for Lithium. If you cut the ground effect mounting straps off and glue them on, it will work much better. If you want to use the Ion Pro 2S Pack you must cut the posts that hold the ground effects in place and glue the ground effects onto the car. Even then, it is a poor fit.

Since it requires a fair amount of extra work to make it fit I don't think we will offer an AtomicBuilt in this style.

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Ion Pro 2S Pack: Snug	Drive Shaft: Long	Weight: 41.05 Grams
Quick Kit: No	Tires: Thick Wall

1. 67 Camero Body
2. 67 Camaro Front Body Mount
3. Long Drive Shaft
4. 67 Camaro Wheel Set and Tire Set

Note this car uses the thick wall tires. All of these parts are sold in the XMOD Generation 1 section.

The Quick Kit is a no go, but the Ion Pro 2S Pack works fine. Its a snug fit, with a slight body bow as pictured, but no problems. I am building myself a little American muscle car now. I love this car!

Yes, I will offer this in an AtomicBuilt

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Ion Pro 2S Pack: Perfect	Drive Shaft: Long	Weight: 38.22 Grams
Quick Kit: Yes	Tires: Standard

1. Civic Body
2. Civic Front Body Mount
3. Long Drive Shaft
4. Civic Wheel Set

All of these parts are sold in the XMOD Generation 1 section.

Yes, this body has enough room to accommodate the Ion Pro 2S Pack or the Quick Kit. In fact, you can fit 4 cells under the hood of this baby!

Yes I do, this is a fantastic AtomicBuilt body with the most room of all the cars. It is also relatively light.

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Ion Pro 2S Pack: Very Snug	Drive Shaft: Long	Weight: 36.38 Grams
Quick Kit: No	Tires: Standard

1. Corvette Body
2. Corvette Front Body Mount
3. Long Drive Shaft
4. Corvette Wheel Set

All of these parts are sold in the XMOD Generation 1 section.

The Quick Kit is a no go, but the Ion Pro 2S Pack fits although there is a pronounced body bow as shown.

No, because of the tight fit I will not offer this in an AtomicBuilt, unless it has a switchblade which yields more room.

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Ion Pro 2S Pack: Snug	Drive Shaft: Long	Weight: 38.91 Grams
Quick Kit: No	Tires: Thick Wall

1. '65 Mustang Body
2. '65 Mustang Front Body Mount
3. Long Drive Shaft
4. '65 Mustang Wheel and Tire Set

Note this car uses the thick wall tires. All of these parts are sold in the XMOD Generation 1 section.

The Quick Kit is a no go, but the Ion Pro 2S Pack fits fine with very minor body bow as pictured, but no problems.

Yes, I will offer this in an AtomicBuilt.

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Ion Pro 2S Pack: Room to Spare	Drive Shaft: Medium	Weight:
Quick Kit: Yes	Tires: Standard

You simply purchase the body kit from your local Radio Shack. It has the body, the front body mount, and all kinds of body effects. You will need a Medium Drive Shaft if you do not already have one. All of these parts are sold in the XMOD Generation 1 section.

Yes you can, the Ion Pro 2S Pack fits with room to spare.

No, but since this body is sold separately as a kit you can buy it from your local Radio Shack and convert the AtomicBuilt yourself after you get it.

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Ion Pro 2S Pack: Perfect	Drive Shaft: Medium	Weight: 42.63 Grams
Quick Kit: No	Tires: Standard

1. NSX Body
2. NSX Front Body Mount
3. Medium Drive Shaft
4. NSX Wheel Set

All of these parts are sold in the XMOD Generation 1 section.

The Quick Kit is a no go, but the Ion Pro 2S Pack fits perfectly. Push the Ty-Wraps back behind the ground effect mounts as shown for a little extra clearance. The rails at the bottom snap around the Lithium cells like they were meant for that purpose.

You bet I will. This is a very cool car and makes a fine AtomicBuilt.

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Ion Pro 2S Pack: Perfect	Drive Shaft: Medium	Weight: 38.16 Grams
Quick Kit: Yes	Tires: Standard

1. RSX Body
2. RSX Front Body Mount
3. Medium Drive Shaft
4. RSX Wheel Set

All of these parts are sold in the XMOD Generation 1 section.

Yes, this body has enough room to accommodate the Ion Pro 2S Pack but not the Quick kit without some body modification. If you want to use the Quick Kit you must cut the posts that hold the ground effects in place and glue the ground effects onto the car.

Yes we do. This is a great AtomicBuilt body. It is also very light.

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Ion Pro 2S Pack: Perfect	Drive Shaft: Long	Weight: 45.96 Grams
Quick Kit: Mount on angle	Tires: Standard

1. Skyline Body
2. Skyline Front Body Mount
3. Long Drive Shaft
4. 350z/Skyline Wheel Set

Yes it uses the same wheels as the 350z. So if you have this car, you can keep your wheels. All of these parts are sold in the XMOD Generation 1 section.

The Quick Kit works if you mount it at a 30 degree angle tilting up in the front. The Ion Pro 2S Pack fits perfectly.

Yes. This is still my most popular AtomicBuilt by a long shot.

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Ion Pro 2S Pack: Perfect	Drive Shaft: Long	Weight: 43.23 Grams
Quick Kit: Yes	Tires: Standard

1. WRX STi Body
2. WRX STi Front Body Mount
3. Long Drive Shaft
4. WRX STi Wheel Set

All of these parts are sold in the XMOD Generation 1 section.

Yes, this body has enough room to accommodate the Ion Pro 2S Pack or the Quick Kit. As you can see, both options work great.

Yes, this is a very spacious body with lots of room for upgrades and deserves to be an AtomicBuilt.

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Ion Pro 2S Pack: Perfect	Drive Shaft: Long	Weight: 40.15 Grams
Quick Kit: Yes	Tires: Standard

1. Supra Body
2. Supra Front Body Mount
3. Long Drive Shaft
4. Supra Wheel Set

All of these parts are sold in the XMOD Generation 1 section.

Yes, this body has enough room to accommodate the Ion Pro 2S Pack or the Quick Kit.

Yes, I sell a lot of Supra AtomicBuilt cars. Its a good body that looks great and has plenty of room.

No, the Lithium cells work fine in a stock car. I would suggest at least a stage 2 motor though since the Stage 1 is very slow.

A Nevada class car with the V2 nuke (11 tooth) and a Ion Pro 2S Pack should turn about 35 MPH on the Dyno, and still be very light, reliable car with good handling. You can do some serious racing with a Nevada.

Take a look at the XMOD Gen1 AtomicBuilt Cars for some ideas on this topic.

This is another question we've been overloaded with, especially since we began selling Mini-Z's. The answer is yes, the Mini-Z bodies will fit, but it will take some modification and possibly some fabrication. Several customers on the Testimonials have done it, feel free to email them for recommendations. Also, check out the forum for others who have experience in customizing bodies.

Since they all use the same chassis, its a matter of personal preference. There are two different body lengths, a medium and a long. (The short position is currently not used.) The only difference is the holes that the rear pod mounts into (middle or back holes), the length of the driveshaft and the position of the rear motor support (facing forward or backward). Some cars will not accommodate certain upgrades, so check the car info box here in the FAQ to see what options each body supports.

I have numerous cars of my own and have sold countless systems to customers, and have yet to have a problem. I even have a couple of customers who have gone beyond the 8.4v limit with the judicious addition of voltage regulation circuitry.

No, and the reason should be obvious. I spend a lot of time researching and buying product to test and sometimes I pay consultants to help me with research, so I would not be inclined to help you cut me out of the picture.

I use Radio Shack Standard Rosin Core Solder .062 diameter #64-008 for most things and the Standard Rosin Core Solder .032 diameter #64-009 for FETs and other fine detail work.

Why yes we do, and its right here.

Sure do. Download the XMOD Factory Wiring Diagram. Big thanks to Jonathan Allen for this one.

Sorry. I know of only one way to get a Stock EP. I buy cars from Radio Shack and strip the EPs out. (Heh - my own little chop shop.) I use the EPs to make Stacked FET EPs, Pro Ready EPs, and V2 EPs. Since I must buy the cars just like you, I would have to sell it for more than you could buy it for yourself. So I recommend you go down to your local Radio Shack and buy your own car, then you will have a parts car handy.

We used to think this was a defect in the boards, but we decided to dig a bit deeper into the stuttering problem and here is what we found.

We suspected it had something to do with the capacitors at C21 and C25 (the ones circled in the picture below.) In order to test this theory we removed the capacitors and tested the EP. When it was on the bench, there was no stuttering, but when placed in a car and used with a strong motor, like the Nuke, it stuttered. Now here is the interesting part, when we replaced the capacitors at C21 and C25 the car still stuttered. We sacrificed several boards to verify this because it seemed too weird. But time and time again, it happened the same way. In fact if either of the capacitors are removed or damaged, the same exact thing happens. We began to wonder if perhaps the capacitors in question where heat sensitive and simply unsoldering them was damaging them. To test for this we removed both capacitors and replaced them, this time without applying power to the board and there was no stuttering, so heat is not the issue. What this tells us is that these two capacitors are very important, and if you remove or damage one of them, and apply power to the circuit, it will fry the board so be careful not to dislodge them when soldering around them. You will solder in this area to do the Ion Pro 2S Pack and Motor Wire upgrades, but as long as you don't bump them, they will stay put just fine.

Sure, I ran across this ESC/Main Board Diagram on a newsgroup. Not sure who created it, but if you know, let me know and I'll give them credit.

Sure, here is a nice graphical layout that Josh Rogers came up with and Funkytones spruced up.

Yes I do. Cyslide gets the credit for this one.

A FET is an acronym for Field Effect Transistor. Your stock XMOD has a pair of A1792 FETs which provide just over 2 amps of usable current.

Absolutely not, the Lithium cells provide more voltage, not more current and stock FETs do fine with the Lithium cells. The motor you run determines if you need upgraded FETs or not.

Unless you have a motor that draws more than the stock A1792 FETs can provide, you will notice a slight performance improvement due to the higher efficiency but that's about it. If you run a high current motor they make a huge difference.

This is the process of piggy backing two or more FETs on top of each other and soldering the legs together so they can deliver even more current. In the case of the 4562, they each deliver 7.1 amps of current, so a double stack yields 14.2 amps.

Since a 2x2 provides 14.2 amps of current, this should run any motor you can physically fit into an XMOD. I do have a couple of mad scientist type customers that are exceptions to this. I am referring to Josh Richardson and Jeremy James, whose cars you can see in the gallery.

No, they are twice as high as the factory, remember we are replacing the 2 stock FETs with 4 higher performance FETS.

1. The first step is to remove the electronics package form the car to gain access to the bottom of the Main Board which contains the logic and ESC (Electronic Speed Control) functions for the car.
2. I then remove the stock A1793 FETs. This step is very tedious because of their proximity to surface mount components.
3. Then I prepare the FET stack by bending the legs on the upper FETS downwards with an IC Leg Straightening tool.
4. Next I use a special FET clamp that I came up with to squeeze them tightly together and maintain proper pin alignment for soldering purposes. This also keeps them tightly together.
5. I then solder these together to make the 2x2 FET stack.
6. And then solder the 2x2 stack to the ESC in the same position as the original FETs.
7. Then I connect the car to my variable power supply and set it to the lowest operational voltage (to minimize damage if anything is wrong) and I connect a small DC light to the motor outputs to test the operation of the FETs in forward and reverse.
8. I bring the voltage up to 8.4 and test again.
9. I then remove the heat sink which does not benefit the stacked FETs anyway and they fit perfectly.
10. Without the aluminum heat sink the power switch slide has nothing to ride on so I switch it "On" and remove the slide paddle. This means you will unplug the Pro Plugs to disconnect the power. This step also removes dead weight from the car.

And that is a FET stack! I will send these parts back to you so if you want the switch to be operational, you will need to cut the heat sink so the FETs fit through and re-install the sink and the switch slide. I leave them off of my cars because of the weight savings.

The factory heat sink does no good when you replace the FETs because you are stacking the FETs higher. The new FETs won't fit unless you cut a hole in the sink so the FETs can protrude through. And when you do this, the sink does not touch the FETs so no heat transfer would occur anyway.

I ran a trial with a Lithium car running a Nuke 130SM with no FET heat sink. The only chassis modification was cutting the plastic on the chassis bottom out over the FETs. Room temperature was 70 degrees and the FETs and motor were both at room temp to start. I ran on the Speed Checker at 30 MPH for 5 minutes and then took it into my living room and drove fast ovals punching it hard out of the corners for another 5 minutes. I checked the temp with my Raytek infrared temperature measurement tool calibrated for Fahrenheit.

Results: At the end the Motor was 137 degrees and the FETS were 90 degrees. As you can see the heat sink is not required and is simply dead weight on a Stacked FET car.

What are you lazy? Yes you could, but the stock FETs would fry at the first sign of a tough load and leave you with half a stack.

No. They run quite cool without it. And since they do not contact a heat sink putting grease on top of them would be pointless.

Sure, it would increase the current handling, but the internal resistance of the factory FETs is much higher than the 4562 FETs, so while this would be an improvement, it will not perform like a 2x2 stack of 4562 FETs.

Sure, but its hardly worth the effort because the stock FETs are not very efficient and the current delivery is quite low. It wouldn't improve performance enough to be detectable. Besides, you can see all the steps needed to perform a FET Stack upgrade. If you are going to go through that kind of trouble, why not do it with good quality FETs to begin with?

The 4562 FETs have lower internal resistance, which makes them much more efficient at delivering power. But the biggest benefit is the ability to handle more current. The stock FETs will handle around 2 amps as opposed to 7 amps with the 4562.

Sure, here they are in a .PDF format:

I have tried this more than once and the result was always the same, the car stutters under heavy acceleration. Every car was from a different batch and the results were the same. The Mini-Zs do not suffer from this problem.

From us of course! Here is the 4562 FET.

The screwdriver included with your XMOD will strip your screws out faster than you can say Jack Robinson. Do your XMOD a favor and get a real screwdriver.

When you are working with anything electrical, a MultiMeter is an invaluable tool. Invest in one and learn how to use it. Repeat after me: "The meter is my friend." Radio Shack has a good selection of them, or you can pick up a Mini Meter from us.

The Suspension Upgrade is a worth while investment that greatly improves the handling. The plastic shock bodies have burrs on them that should be sanded off. I use a small flat hobby file to do this job.

You can always center the steering with the trim buttons on the controller, but if it takes more than 3-4 clicks you are giving up turning radius one direction or the other. Remove the horn and center it.

The Ball Differential that comes with the AWD kit is no good for Lithium. Lithium generates too much power for it and before long it will start slipping. You will hear your motor revving higher. If you suspect a bad diff, hold the pinion still and one wheel still. If you can turn the free wheel past the slop in the rear end, you have a bad diff.

The speed testing was done without FETs as stated. The speed test doesn't place a torque load, it only measures top speed. Therefore I am able to run the Nuke without FETs. If you try that real world, it will fry the stock FETs in short order.

Not with the stage 1 or 2, but you need to be careful if you are using it with anything that pulls more current than these. I have not tested them with anything else so you are on your own. If you learn something, let me know and I will post it here.

I have been running the Stage 2 motors with good success, and if you want the ultimate take a look at the new Nukes on the Motor page.

This was my first motor roundup and I used a Tamiya Speed checker to test with. This device measures top speed only and does not take into account torque, which goes down substantially as the speed increases, unless more current is drawn. The speed testing was done without FETS as stated. Therefore I am able to run the Nuke without FETs. If you try that real world, it will fry the stock FETs in short order.

Motor	Car	Drive	FETs	Power	Pinion	MPH
RS Stage 1	Bone Stock Test Car*	2WD	No	RS NiCad	8 Tooth	10.56
RS Stage 2	Bone Stock Test Car*	2WD	No	Lithium	8 Tooth	19.26
RS Stage 2	Bone Stock Test Car*	2WD	No	RS NiCad	9 Tooth	17.40
RS Stage 2	Bone Stock Test Car*	2WD	No	Lithium	9 Tooth	25.48
RS Stage 2	Bone Stock Test Car*	2WD	No	RS NiCad	10 Tooth	18.64
RS Stage 2	Bone Stock Test Car*	2WD	No	Lithium	10 Tooth	24.85
RS Stage 2	Bone Stock Test Car*	2WD	No	RS NiCad	11 Tooth	21.13
RS Stage 2	Bone Stock Test Car*	2WD	No	Lithium	11 Tooth	31.07
180S	Bone Stock Test Car*	2WD	No	RS NiCad	11 Tooth	16.8
180S	Bone Stock Test Car*	2WD	No	Lithium	11 Tooth	22.4
SS 130	Prototype Test Car 11	AWD	No	Lithium	10 Tooth	25.5
Nuke 130SM	Bone Stock Test Car*	2WD	No	RS NiCad	11 Tooth	19.88
Nuke 130SM***	Bone Stock Test Car*	2WD	No	Lithium	11 Tooth	31.69

*Testing was done with a brand new bare-bones stock car that I did nothing more than solder a Pro Plug onto the stock Board wire to allow me to change the batteries out quickly.

**Notice the anomaly of the 9 tooth on Lithium being faster than the 10 tooth. I thought this was a mistake after I complied the test, so I went back and ran the test again with different batteries, different motors and got the same result. Seems that the 9 tooth is a sweet spot for the Stage 2 motors.

***The Nuke 130 shows an definite increase in speed, but the most impressive aspect of this motor is the amount of torque it produces.

I was in the process of testing some prototype motors and I thought it was about time I tested all the motors because so much has changed since I did the first Motor Roundup.

These test results represent what you would get if you had the perfect EP/battery combination with as much current as the motor asked for and zero voltage loss. The only thing even close is the V2 which has very little loss, but the purpose of this test was to make a solid motor to motor comparison, which requires a consistent power source.

Bottom line is, these speeds will be higher than what can be achieved in a typical car with an EP and batteries, but will be very accurate in relation to one another.

This testing was done 3/5/2002.

"Test Car 202" has no bearings and is a completely stock 2WD car minus the EP with a modified rear motor mount to support the motors being tested and allow quick access to change motors. The tires are medium slick and are glued to the rims to keep them from ballooning at high speeds and influencing the results. An 11 Tooth Pinion and Blue Bevel Gear were used for all tests. A harness was soldered to each motor for the 'in car' tests to ensure no power loss, and a Tamiya speed checker was used. The motors were powered directly from a variable power supply.

All test cars are numbered, and when a test is completed the car is stored in case there is a need to go back and check something later.

I eliminated batteries from the testing process in favor of a more consistent Sinometer HY3020E variable power supply. When using batteries, they run down and you do not get accurate results. I even eliminated the EP from the equation. This was also done to increase accuracy since the EPs cannot deliver consistent results as they heat up. The more motors tested, the worse the results become since the EP gets hotter and loses efficiency. As you can see some of these motors draw quite a bit of current, and the power supply can supply up to 30 amps and 30 volts without breaking a sweat. This is the best way to get the most consistent results.

I also took RPM readings which are shown in the chart. These were taken with a laser tachometer and an optical disc mounted to the motor shaft. The disc is painted with a black stripe that the laser registers when it passes. All readings were taken at both 6 volts and 8.4 volts as indicated. It should be noted that the industry standard for quoting RPM is at 6 volts. You will also find the amperage draw in the chart. This was read at the same time the RPM readings were taken. The motor being tested in the photo is a Radio Shack Stage 2, which came out at 30,250 at 6 volts. That reading matches the Radio Shack stated RPM for the Stage 2 motor pretty closely.

Source	Motor	Volts	Amps	MPH	RPM	RPM Amps
Radio Shack	Stage 2	6	0.9	25.5	30,500	1.1
		8.4	1.3	32.3	38,250	1.3
AtomicMods	SS130BB Ball Bearing	6	0.9	24.8	36,500	1.1
		8.4	1	29.2	46,800	1.3
AtomicMods	ProStock	6	1.1	26.7	31,950	1.5
		8.4	1.6	36.0	40,100	2.4
AtomicMods	Frankenstein	6	1.5	31.1	40,880	1.5
		8.4	2	41.6	54,650	2.6
AtomicMods	FatBoy HC	6	1.9	31.1	41,000	2.0
		8.4	2.4	43.5	55,700	2.4
Discontinued	180 High Torque	6	1.2	24.2	32,500	1.2
		8.4	1.8	28.6	40,100	1.9
Discontinued	SS130	6	1.1	24.8	32,250	1.4
		8.4	1.4	31.7	40,100	2.3
Discontinued	Nuke 130SM	6	1.5	29.2	38,100	1.7
		8.4	2.1	39.8	52,600	2.1
Prototypes	Nuke HC	6	1.7	31.7	39,000	1.8
		8.4	2.2	41.6	54,850	2.4
Prototypes	Blaster HC	6	1.7	31.1	38,650	2.1
		8.4	2.2	43.5	56,050	2.6
Competitors	Xmodspeed R-Tune	6	1.3	22.4	26,912	1.4
		8.4	1.5	27.3	35,150	1.6
Competitors	Team Orion 180	6	0.4	14.3	19,700	0.5
		8.4	0.6	19.9	27,600	0.6
Competitors	6	0.4	14.3	18,700	0.4
		8.4	0.5	19.9	26,500	0.5
Competitors	NML Stage 11	6	1.1	22.4	30,000	1.0
		8.4	2	29.2	37,950	2.3

No. The SS130 is in fact a better motor. The tests unfortunately do not reflect torque which is very important. The SS130 not only makes more torque than the Stage 2, it is also better at handling the higher Lithium voltages while keeping its cool.

Several prototype motors were tested, and I am almost ready to go to market with them. But please don't wear me out about it. I'll post them on the site, when I have a sufficient quantity of them in inventory.

Right here!

We test all of our EPs for range and most of them are around 40 feet, and the best reach all the way to 60 feet before breaking up. These extra long range units are reserved for Stacked FET and V2 EPs. The ones in the 40 feet range are used for Pro Ready EPs. Anything below 20 feet is not up to our standards and we either tune it or replace the receiver and re-test it. Note that range decreases with a hot motor because the brush arcing increases with current and creates more noise.

The problem is most likely the inductors ("L1" and "L2"). You will need to replace these to restore the factory range.

Related Links:
XMOD Gen1 Range Repair Kit
Tutorial - XMOD Generation 1 - Range Repair Kit Installation

You most likely just need to fine tune the receiver circuit. You do this by turning the ferrite core adjustable inductor. It is the off white cylinder next to the crystal. To do this, you have to scrape away the waxy substance in the top, and have a friend play with the controls at increasing distances while you slowly adjust it using a small screwdriver. Sometimes the range problem lies within the controller and it simply needs to be replaced. We sell the XMOD Stock Remote Controller here.

Take a look at the Ion Pro 2S Pack Kit Installation Page to see how to gain access to the steering pot.

I have seen this on several of my brand new cars and each time it was a bad controller. It simply needs to be replaced. We sell the XMOD Stock Remote Controller here.

Stuttering is a problem with the MainBoard not the receiver so you will need to replace the MainBoard itself to solve this problem. We sell the replacement MainBoards here.

Unless any damage has made it to the MainBoard and taken out the logic, the Receiver Range Repair Kit should solve the problem. If your servo is locked over to one side, it is a good chance that the MainBoard is gone. If so you will find replacement receiver boards here.

Check the wires, they are quite brittle and prone to break, chances are you may have snapped one of them in the process of installing the inductors.

The range repair kit is not magical and only replaces the factory inductors, restoring factory performance. They are the exact same size and value as the factory ones.

They determine which frequency or channel the car will operate on. You need to be on a different channel form your buddy in order to race, unless you want to drive 2 cars from the same remote for some XMOD Ballet (this is a hoot). It is a good idea to have a blank channel between the cars since there can be a bit of bleed over between channels. Radio Shack sells Channels 1-12 for the XMODS. Here is an interesting tidbit. The XMOD crystals, work in Mini-Zs just fine, but the radio systems are not compatible, only the crystals.

Sorry, it took me way too long to find them and I'm not inclined to help you cut me out of the picture. After 6 months of dedicated effort I found one supplier that sells the correct inductor into the US and they only sell in 500 unit lots, so it wouldn't help you anyway.

Here is a very informative article about inductors and how they work.

Unfortunately no. They operate on a proprietary system that is not compatible with any aftermarket controllers.

Sure do. Download the XMOD Factory Wiring Diagram. Big thanks to Jonathan Allen for this one.

Try another controller as those fail quite often, also try new crystals as they also fail occasionally. Also make sure you have a fresh battery in the transmitter. If these don't solve the problem, you have a bad Receiver or Mainboard.

Not likely, the factory wire is tuned to the receivers wavelength. Try adjusting the pot as discussed above.

Yep, download the XMOD Factory Wiring Diagram. Big thanks to Jonathan Allen for this one.

Don't believe in reading owners manuals do ya? Flip the "USER" switch on the controller and that will reverse it.

No, The highest voltage you can go to without voltage regulation is 8.4 volts. Stacked steering FETs do not allow you to go any higher. I have tried this and Stacked 4562 FETs on the steering actually makes it "twitchy" because the 4562 FETs are more responsive and this makes the car harder to handle. I like the response curve on the stock FETs far better.

This is usually the result of the servo leads being too long and shorting out against the back side of the board. Trim the leads flush with the board and that should take care of the problem. Take a look at this photo for clarification. However, if you left the power on too long in this shorted condition you can fry the steering servos and even the board logic. If trimming the leads does not solve the problem you will need to replace the MainBoard. Sometimes simply loosening the two long screws that hold the EP (Electronics Package) in place will alleviate the symptom, but you should still trim the leads.

The other possible cause for this is unequal resistance on one of the steering resistors. This can be simply a loose or incomplete solder joint on the resistors. Take a look at the XMOD Generation 1 Tight Turns Installation Tutorial and re-solder the resistors R26 and R27. If that doesn't solve the problem, you have a bad steering logic on the MainBoard and it will need to be replaced. You can buy new MainBoards here.

If it glitches on one side only you can flip the reverse switch and if the glitch swaps sides, you have a bad potentiometer in your radio controller. You can also try a friends controller to troubleshoot this problem. Don't worry, we sell the XMOD Stock Remote Controller if you need a replacement.

Chances are you broke a servo wire loose, they are very fragile and you need to be careful with them. Its an easy fix with a little soldering iron.

You have a servo with internal damage. This usually happens after an impact with a stationary object. The solution is to replace the Stock Steering Servo.

Sorry. I did the research, found the product, tested it, packaged it, and developed the support resources and installation "How To" which you will likely use when you do the upgrade. So I am not inclined to help you cut me out of the picture.

Make sure there is no solder or wire shorting the 3 pads together, you may need to drag a hobby knife between them to make sure they are separated.

The jittering doesn't have anything to do with Lithium cells specifically, it is a result of the higher voltage. You will see the same behavior with 6 cell Ni-Cad upgrades as well. What is happening is the servo is seeing a higher voltage therefore has more power, just like your drive motor. The servo is always trying to auto center itself, and because of the extra power it has, it now returns to center with more force causing it to overshoot slightly and then re-center. When the car is in motion, the resistance of cornering prevents it from overshooting the center. This behavior is normal and will not hurt anything. In fact, the cars steer with more authority and handles better because of the higher voltage. I have cars that have been running the higher voltages for 2 years and still work fine. The V2 Regulated Power Management Board solves this issue. You can read more about it at the V2 Power Board Q&A.

The stock medium and long shafts are 77mm and 81mm long respectively.

Yes. GPM XMOD Gen1 Billet Aluminum Front AWD Axles.

Look at the front rims from the top, you will see where the steering horns almost touch the back of the rims. Some cars rub more than others, and you will see grooves cut into your horns by the rims if yours rubs a lot. I just trim a notch in them so they miss the wheels. Make sure you have a sharp pair of cutters otherwise you may break the horn. Take a look at the XMOD Generation 1 - Steering Knuckle Trimming Tutorial for details.

This problem can be a combination of things. The factory Arms are often not symmetrical, and some cars are worse than others in this regard; but none of the cars are perfect. Also the shock bodies need to be filed to make sure they are smooth so you don't have shock binding. The best solution is to go to Billet Aluminum suspension parts that are perfect and bind free.

You can take the shocks out, but this will ruin the handling.

You can, but it will wear through them. I recommend upgrading to metal bearings.

The Ball Differential that comes with the AWD kit is no good for Lithium. Lithium generates too much power for it and before long it will start slipping. You will hear your motor revving higher. If you suspect a bad diff, hold the pinion still and one wheel still. If you can turn the free wheel past the slop in the rear end, you have a bad diff. Note the AWD kit comes with a ball diff and a gear diff. The one that is mounted in the front drive gear assembly is the gear, the loose one for the rear is the ball diff. Use the stock white gear diff that comes with the car instead of the red ball diff in the AWD kit and you will be fine.

This simply means you have taken your differential apart and glued the gears in place with some glue to 'lock' it up. This has the effect of making it a full "Positive Traction" differential. Great for drag racing, but lousy for road racing because it causes the rear end to spin out. Some people use Play Dough to make it reversible.

Use the stock white gear diff that comes with the car.

Put some toilet paper into the gears, LOL. This is better than glue because you can remove it later.

That's a good question. On a NiCad car, because of the low power, the extra friction slows it down. On the other hand, if you go Lithium without the AWD, the car cannot maintain traction so it will simply sit and spin out and be uncontrollable. The best combo is Lithium with an AWD upgrade.

AWD makes the steering more controllable, but wider. A 2WD car can spin its rear end around and turn on a dime but its very hard to control and you will lose the race every time. Consistency wins races.

Your wheels should keep spinning 3-4 revolutions after you flip them by hand. If they stop immediately you have a binding problem.

You break the car down and check each sub assembly by hand. The shafts should slide easily into all bearings and nothing should require any effort to put in. If a shaft doesn't slip into a bearing, file it until it does. All bearings must be clean and there can be no dirt or grit or hair anywhere. The wheel nuts must be just loose enough to keep the wheels running true but not so tight as to restrict them. The wheel shims help here greatly. I file all of the axles on the AtomicBuilts when I build them. If you buy the Billet Aluminum Joint Cup Shafts they fit perfectly and do not require any filing.

Two reasons, it is dead weight and it tends to bind the suspension A-Arms on some cars preventing smooth travel.

Yes, this really makes a big difference in controlling the car.

Yes, the Lithium generates too much power for 2WD and the car will simply spin out of control. If your goal is to break the record for XMOD donuts, than by all means, stick with the 2WD.

There are two different body lengths, a medium and a long. The short position is currently not used. The only difference is the holes that the rear pod mounts into (middle or back holes), the length of the drive shaft (medium or long) and the front motor mount position, (facing forward or backward).

Yes you can, you will need do some trimming since the tires will rub with some bodies. We recommend using the 8.5mm on the front.

They are 9.5mm wide and 20mm tall.

Take a look at the Tire Q&A, we have a lot of info posted there.