DLuders

Yes, using the heavy Lego Power Puller wheel/tire combination would lower the Center of Gravity, and help resist sideways rollovers. I hope to shop all of this later today in my YouTube video....

@ mrklaw: The 32072 Technic Knob Wheels can be used as non-slip gears on a 9L Technic Axle, to replace the 9398's Differentials.

The Lego Group could redesign some elements of the Vampire GT car to save costs (especially if the Lego Cuusoo "Supporters" will buy the set only if it is below a certain price). They may alter the design to integrate some newly-available part(s). In the Technic theme, the Vampire GT's gullwing doors have only appeared on the Lego 8466 4x4 Off-Roader set, and the number of official Lego Technic Supercars can be counted on one hand. The "subject matter" (a supercar) would be far more interesting than the same-old Technic Tractors being offered every year. Something like the Vampire GT's gearbox hasn't been seen in a generation (since the 8880 Super Car from 1994), so it would be "new" to a whole new set of teenagers.

I should have said that, if you want the 9398-A model to CONTINUE ROLLING downhill, the A-model's rounder body will allow it to roll. The more-boxy 9398-B model will START TO ROLLOVER easier than the A-model, but will quickly stop rolling due to its shape.

I like it -- the motorized Lego Technic 9395 looks like it can go on safari! You let your little boy play with it too, don't you? Those 3rd-party tires sure help its crawling abilities. Since you used a differential in the rear and a solid axle in the front, do you think that same arrangement would help the 9398 4x4 Crawler?

@ davidmull: The 8879 LEGO® Power Functions IR Speed Remote Control costs €13,99 on the Irish Shop.Lego.com website, while on Bricklink the (identical) 64227 "Electric, Power Functions IR Speed Remote Control Unit with Dark Bluish Gray Base" is for sale at a lower cost.

The 9398-B model is more likely to roll over because: 1) It has a higher center-of-gravity. 2) It has a nose-heavy design, not centered on its four wheels like the 9398-A model. I hope to prepare a YouTube video tomorrow to show these characteristics. Side-by-side comparison will show how the A-Model is the superior design.

NO -- don't pull it off the Lego Cuusoo site! The Vampire GT Supercar MOC is one of the finest examples of Lego Technic that has a good chance of being made into a real Lego set. Here's why: 1) It looks cool -- many children and their parents will love the gullwing (batwing?) doors 2) The 5-speed + Reverse All-Wheel-Drive transmission has not been offered in a Lego Technic set before 3) The "Hand of God" steering (and lack of Power Functions) makes it affordable for many families I don't agree with Erik Leppen's assessment that "there is no point voting for it". If ANY Lego Technic model should be made into an official set, it's the Vampire GT Supercar! :thumbup:

Here is the Lego Technic 9398-B alternate model (the "4x4 Offroad Truck"), with Rok Lox 1.9 Comp Tires on the standard Lego 44772 wheels. The axles are raised by the larger-diameter tires (for greater ground clearance), and the wheel wells are filled better than the stock Lego 54120 tires:

I just built the Lego Technic 9398 4x4 Crawler's alternate "B-Model" -- the 4x4 Offroad Truck (with its tall cab-over-motor design). Using the downloadable PDF Building Instructions available from Technic.Lego.com, it took me around 4-1/2 hours to assemble the B-Model from start-to-finish (the same time that the A-Model took). From the 21 pictures I placed on my Flickr photoset, you can see from side-by-side comparisons that the B-Model is much taller, and has a different center-of-gravity balance point than the A-Model. The 9398-B has more extra parts (and hence is slightly lighter than the A-Model), but it is nose-heavy: The two smokestacks and Power Functions Receiver will break off in a rollover crash (the kind that Sariel likes! ), since there is minimal protection. Once a rollover begins, the A-Model continues to roll over easier than the B-Model due to its more-rounded shape, and is much more robust (i.e., no parts break off). The cab-over-engine design is more typical of European truck designs than American designs. I did not apply the stickers to the A-Model, and the B-Model's building instructions does not come with suggested sticker placement: Overall, the "building experience" of the 9398-B Model's assembly was enjoyable. The first two-thirds of the build was identical with the A-Model's build, since the chassis is the same in both variants. They CRAWL the same but the B-Model's weight-forward design and top-heavy body shell makes it more prone to tipping over. Modifying the 9398's body shell is easy; efferman already made an alternate "C-Model". You can design your own body shell using P4trickvH's 9398-B Model Lego Digital Designer (LDD) .lxf file. Although some parts are not included because they don't exist in LDD, you can easily see what is possible.

@ z3_2drive: The larger Lego Power Puller wheel/tire combination weighs a lot more than the stock wheel/tire combination that came with the 9398 set. The 22969 Power Pullers Wheel (20.560 grams) + the 32298 Power Pullers Tire (170.000 g) = 190.560 grams, while the stock 44772 Wheel (15.400 g) + 54120 Tire (43.600 g) = 59.000 grams (over 3 times less weight). So, the Power Functions Servo Motor may have trouble hefting all that weight. Plus, there may be more tire-to-pavement friction since the Power Puller tires have a greater "contact patch" area. @ MarkV: You can mail-order the 9398 4x4 Crawler set in the USA from Shop.Lego.com and Toys-R-Us. Price = $199.99 (before sales tax). Although you could drive to an official Lego Store, you could save yourself fuel and just wait a few days to get one shipped to you.

Did you use Artifexcreation's Brick Lights, or regular Lego Technic LED lights?

Your Mercedes-Benz Geolander (G-Class) Light Armored Patrol Vehicle (LAPV) looks good in orange!

I like the 5th wheel parking mechanism for getting into tight spaces! Features: "driving, steering, working steering wheel, parking, independent front suspension, differential lock, 4 speed gearbox."

There are a LOT of features in this Lego Technic creation! You certainly did your homework. The two bad guys will order one of these Escape Helicopters!

Like one of RoscoPC's Lego Formula 1 cars (as rendered by Blakbird)?

On his website, Erik Leppen posted a 21-MB PDF Building Instruction file for his LOW Lego Technic HYPERCAR. It has also been posted to Rebrickable.com , where he wrote that this Lego "Technic supercar [is] named Hypercar because it is only nine studs high (not counting the wheels). The body, including windscreen, is part of the structure and gives it rigidity. The limited height and this structure made that no space was left for a gearbox. Features steering, [independent] suspension and a [rear-drive] V10 piston engine." The doors open manually -- see the 11 pictures on his webpage.

@ efferman: I think your wheelbase is fine as-is. Many of raus' Lego Technic Rock Crawlers have a similar wheelbase, and they do just fine on the rocks:

@ vwpint: This webpage sells the Lego Technic 9398 4x4 Crawler, and ships to all European Union countries (like Estonia). Use this online translator to copy/paste the German text into Estonian.

Philip Wulff Eckert posted this YouTube video of his "Lego Nightrider sportscar with motorized functions such as height adjustable suspension, foldable roof, active rear wing, head protection bar, engine hood that opens and different lights. Can drive and steer and has build in headlights and taillights. Transparent engine with build in lights than can be switched on and off." It is REALLY WIDE and has a nice mix of older studded plates and newer Lego Power Functions elements. http://www.youtube.com/watch?v=nHxIkkebiBg

Nice miniature version!

I would look at Han's various Lego Technic trailers for ideas. He's got some wonderful designs. The 9397 Logging Truck has an open frame, so you could probably innovate:

@ z3_2drive: There are several 1.9" RC tires on sale at the bottom of this RC4WD "Hot Deals" webpage. Any 1.9" (48mm Inside Diameter) tire in the 37mm-48mm widths will fit the Lego 44772 wheels. There are some tires on that webpage that are good bargains.