MST XXX-Rally vs. XV-01

[Blaster 75]

I haven't seen a direct comparison between these two, so I thought I'd put a few of my thoughts here. Both cars are excellent platforms, the best rally cars you can get from what I've seen. I have an XV-01 Pro that has received a ton of hop-ups and tuning, and a XXX-Rally that has been disassembled and rebuilt carefully, shimming as necessary, so both cars have been built to a similar standard, and both use high-quality servos and sensored brushless systems. Each has some areas that need improvement; each has some great features.

Handling- The out-of-the-box setup on the MST was awful. The springs are very soft, the shocks are lightly damped, and the rear had positive camber, all of which made the car snap oversteer in the middle of the corner. I'm still experimenting with setup, but have much heavier blue Tamiya springs on the front with 900 wt., and red Tamiya springs on the rear with 650 oil. In contrast, the Tamiya was great with stock settings, has responded predictably to tuning, and transitions better. Both could use more steering angle for low speed work. The XV-01 is easier for me to drive fast on any surface.

Rough Surface- This is where the MST shines. Although it doesn't jump as well as the XV, which I may be able to tune out, it's longer suspension travel and higher ride height mean that the MST stays on course better over rough or broken pavement, bricks and the like. The XV is no slouch, but required longer shock shafts to maximize ride height, which is still lower than the XXX, and travel.

Durability- Nothing unusual to report here. The XV-01 requires aluminum suspension mounts. The MST needs aluminum front uprights, which cost $50. I've broken ball cups on each. Both are nice quality cars.

Protection- XV-01 all the way. Inner fenders, electronics box, battery box, little foam seals on the ball cups, compared to little foam seals on the MST.


Misc.- The MST is much noisier than the XV. It requires disassembly to adjust gear mesh, but has a very nice clamp/cam motor mount. It has ball diffs, which some people hate. Hop ups are expensive, and only from MST. Parts availability is tough- Blackstar Hobbies and RC Mart have been my best bet. Available only as a RTR, which meant that I had to disassemble and reassemble instead of just build it right the first time, and dispose of the electronics. Cramped electronics layout, even with a Tekin Rs Pro. Does not come with turnbuckles. Comes with CV axles front and rear, and has nice hardware and excellent, attractive plastics. Came with great tires and a painted and decaled Tamiya body. Both diffs were very loose and the mesh was loose as well. Mine came with a pit towel, too.

My XV-01 was a Pro kit, which came with a bunch of sweet hop ups, like CV axles, TRF shocks, and blue balls. It still came with crappy Phillips head hardware- inexcusable for a kit this nice. Even though the Pro didn't include a body, I feel that it was a better value than the standard kit. It took plenty of shimming to get the slop out. Rally Block tires are only good in dirt. Standard kit doesn't include turnbuckles or CVs. The suspension mounts should be replaced with aluminum while building the kit. Requires a small speed control- that Traxxas VXL 3s you have laying around won't fit, and neither will a Sidewinder. This chassis deserves a sensored motor, anyway. The XV is a heavy car, much heavier than the XXX.



Really, both are good cars. You can build a damn nice XXX for quite a bit less than an XV-01, and have just as much fun with either. At this point, I prefer the XV- it just feels better to me, and it's more fun to drive hard. The XXX needs more tuning to drive well, but may end up being the superior car once I have it dialed in. The parts availability does bug me- it means that I have to keep spares around or wait a long time to repair. If it's half decent tomorrow, I'll post some pics of the cars together for some visual comparisons.

[colbynobo]

Excellent. Thank you for making this post. I purchased a used XV-01 a few weeks ago and have only put 2 batteries through it. I like it a lot and was thinking about also getting a XXX Rally to run alongside it. I briefly owned a MST FXX-D, so I'm familiar with their quality. However, being a drift car, I never broke anything so didn't have to deal with parts availability. Again, your quick review will help me with my decision.

How easy is it to make adjustments on the ball differential? Can you just pop one side of the drive shafts off for quick access?

[BoulderDan]

thanks, that was a great help. between, the body, ground clearance and shaft v belt, i'm confirmed on the XXX. Just need to find another C note and it's ordered. in the meantime i blast around on a losi 1/14 mini rally, which is a ball anyhow.

[Blaster 75]

It's very easy to adjust the diffs on the MST- pop a camber link, pull an axle, there ya go. I did forget to mention one tiny issue on it- The MST uses long arms, and has less arm to wheel clearance, so "reinforced" rally wheels won't fit without trimming quite a bit from the wheel.

[Natedog]

Blaster75, thanks for the comparison!

[Blaster 75]

I've been racking up the miles lately on the MST.Melted the rear diff today, so gear diffs are next. The long arms cause binding as the wheels pack with mud. I am pretty sure that it will be nearly impossible to bind the steering with debris- this thing was packed and filthy, and the steering still worked perfectly. The hop-up aluminum knuckles listed as replacements don't fit-not even close-, so there are plastic stockers on it now. I'll be cutting some carbon doublers soon to prevent future breakage. I'm still very happy with the chassis, and it has been responding well to tuning.

[colbynobo]

I wondered whether the elevated steering rack did a good job of avoiding debris - good to hear that this is the case.

I briefly owned a TLR 22-4 that I purchased used but got rid of before the ball differentials needed servicing. What kind of motor are you running in your XXX-Rally?

Does the motor being mounted towards the front make a significant difference in how this car pivots compared to something like a TC4 or a V100? Obviously it won't be as effective as what we experience with our XV-01s, but is it kinda close?

[Blaster 75]

I'm using a 10.5 Trackstar/Tekin RS Pro combo in the XXX, with a FDR in the 6.2 range. It's zesty, but very controllable. The front motor definitely improves turn-in compared to V100 or TC4. I'm working on a TC4 Factory Team rally conversion as well, so I'll be comparing that one, too. I really don't like all of the torque steer the shaft drive has- it's difficult to hold a line on slick, narrow courses, while the XV-01 accelerates straight.

[JohnnyAnguish]

I was thinking about building an XV-01 because I love my HPI-RS4 Rally, but I'm scared I'm going to bust it up and not be able to get parts for it. My biggest concern is that it looks like you need to remove 2 screws to change the battery on the Tamiya? Is there any other way? That doesn't seem like something I would enjoy.

[Blaster 75]

The two screws really aren't much of a hassle, once you get used to it. No harder than removing a body and battery hold down. Parts consumption on my XV-01 has been very low, and parts have been easy to come by. With HPI parts being almost impossible to find, I'd definitely spring for the XV.

[colbynobo]

I sacrificed a bit of crud protection by cutting a hole in the top of the battery box and running the Deans connector and the balance connector up through it. I accept the risks of charging a battery while it's still in the car and not enclosed in a lipo sack. If something goes wrong I'm going to have to hammer throw the whole rig over the berm in my back yard. Otherwise, removing the 2 screws on the chassis bottom would have been enough of an inconvenience - albeit minor - to have convinced me to leave the XV-01 in the basement each day. Never underestimate the power of laziness. The XXX-Rally sounds like it may not handle quite as well, but the quicker battery replacement has the potential to encourage more driving time.

[KellyC]

Thanks for the comparison. I also just read through BVRC's thread on the MST XXX Rally and am about to pull the trigger.
Are people starting to find hop ups from the aftermarket for this car?

Also, since the MST Rally uses Tamiya bodies, I assume the Tamiya rally driver interior will work with them, correct?

[Blaster 75]

Any required or desirable hop-ups are available from MST. I don't see any aftermarket parts on the horizon- the chassis isn't very common, and doesn't have any glaring strength or design flaws.

[KellyC]

Thanks for the reply, Blaster.
Another question: which rig packs up with dirt worse? The XV-01 or the MST?
I had a XV-01 for awhile, loved it, but the rig just constantly packed dirt in around the front wheels and motor. I live in Wa. state so just about every run required heavy cleaning/clearing of dirt. I did all the Turtle/BVRC mods like wider finders, wheel well skirts, etc. but couldn't keep the dirt from loading up.

I really want to get another scale rally car but am thinking the MST may not load up as bad since the motor is more at mid-car, versus right over the front end.

[Blaster 75]

The MST is a shovel on wheels. It does have an almost bind-proof steering system, but the chassis is full of crap after every run. I still haven't made any sort of shielding for mine, and won't until I get the damn thing to drive the way I like. A front spool and rear gear diff got me in the ballpark, but the front CV shaft snapped, and I've been waiting forever for a double-Cardan replacement. Hopefully, I'll be rolling in time for the next round of the championship.

[RandallRedwood]

You mentioned easy slipper diff adjustment. Can you explain further

[sethstiles]

I like the MST looks and price and overall quality looks good too. I'm in the market for a rally car, small scale or 1/10th. I've heard a lot of mixed reviews on the XV01 in terms of complexity and maintenance but overall quality is really good and tends to be the industry go to car. The Tacon Ranger looks great too, great price and great reviews. NitroRCX says parts can get out to the continental US in 5-7 business days so that's good. I even like the Dromida 1/18 rally car and there are looks of good upgrades available. Bit worries about small scale limitations on performance like GC. Any other suggestions for me? I'm open to a build kit but I have never done one before.

[Natedog]

Originally Posted by sethstiles

...I even like the Dromida 1/18 rally car and there are looks of good upgrades available. Bit worries about small scale limitations on performance like GC. Any other suggestions for me? I'm open to a build kit but I have never done one before.

LaTrax 1/18 rally car for smaller scale, my LaTrax SST (now called Prerunner) has been a great truck on stock 6cell nimh batteries, only broken one stock front cvd and it's been run hard!
https://m.traxxas.com/products/latrax/rally

Here's current truck version
https://m.traxxas.com/products/latrax/prerunner