Limitless The BlackCat builds his first 'true' speed run car

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Welcome to the dark side. I started with Traxxas as well and remember seeing you in the forums. The biggest difference is when you buy an Arrma almost everyone starts customizing everything on it right way. I don't know that there is any part of an Arrma that you cannot get after market or fabricate. Also this forum is great. Great people that no question unanswered. Everyone one is up for holding your beer while you try something new.

I'm a bit late to the party on this one, too many moving parts these days.
Something I did notice was that, in installing the tubing on the rear shocks, Raz was doing it "the hard way". Not sure if others are aware, but there IS a faster/easier way...and, as Raz isn't into RC boats, he might not know. In RC boats, we use that same tubing as water lines, running water to the motor cooling jackets & ESC cooling plates (since boats can't exactly have fans, or 'access' to cool air), as well as (sometimes) to the water-cooled motor mounts. The thing is, that tubing is available in different diameters. Through the company I purchase from (OSE), that tubing is available with IDs as small as 2.8mm, and as large as 4.2mm, with several other diameters in-between. Using tubing with the same, or slightly larger, diameter than the shock shafts will make installing the tube a LOT easier. The other problem of using tubing that has a smaller ID than the shady diameter is that it will, eventually, completely inhibit movement of the shaft, leading (essentially) to the shock "seizing", because the tubing 'attaches' itself to the shaft. By using tubing that has an ID slightly larger than the shaft 's diameter, it allows the tubing to maintain its 'separate' nature from the shaft. While I prefer to use O-rings & nylon discs inside the shocks, I've been using tubing on the outside for several years. Just my 2¢ worth.
Yup installing the nitro tubes are a PITA and a larger diameter would make it much easier. There is no reason (that I can think of) for it to be that tight. However, mine loosened up after a few runs and bottoming it out. They aren't floating but they do move. It's basically a bump stop so the key is to use silicone (soft) tubing. The hard PVC plastic has no cushion. If it's hard and you bottom out you get an infinite spring rate and everything else takes the impact. In this case the control arms are a bit floppy and provide some more cushion.

If I had to do again, I would spend less time building it to break the sound barrier and more time driving. I live in San Jose. We have way too many people and the roads suck pretty bad in most places. The best I can find is 1600 ft of sort of smooth road. It's still have road turtles and utility covers. So all the tweaks I did/doing aren't really that helpful given the constraints and I'm having to tweak it more for my conditions vs Raz's 5,000 ft Runway.

Your paint scheme is awesome. It's asymmetric and helps you see which way the car is facing when it's down the road and just a little dot on the horizon.

This might be the tire thread that was referenced.
https://www.arrmaforum.com/threads/limitless-speed-run-tires.49785/
I ended up with the GTJ03-XB1. I figured the soft compound would give me a bit more grip and the weather is fairly cool in the area. They are kind of balanced.
1666463454693.png

If I find space to run 150 mph (and I'm good enough) I can move to a harder/less friction compound or foams.

I keep the hoons around for building and testing. I don't want the car sitting on the good wheels getting flat spots (rims) and picking up all the crap on my work bench.
 
Thanks for that info. Hopefully, my 'decision' didn't turn out to be a "too soon old, too late smart" one - by the time I read your reply, I had already ordered the Roto-Lok motor mount...along with a few other goodies from Scorched Parts (Island Hobby Nut is currently "out of stock" on the Roto-Lok, and, b since that's the 'primary' item I was ordering, had to order direct from Scorched Parts).

The "other goodies" consists of 8mm ID spacers, front & rear Ti skid plates, Ti lower suspension pins (not sure why they call them "suspension pins", when they're for mounting the bottom of the shocks...lol), Ti shock standoffs, Ti pillow balls, and the 7075 bell crank/servo-saver-delete.

The plan/goal is to get any/all chassis upgrades installed before the ESC/motor combo, since, at $500, that's the single (or two, depending on how long looks at it) most expensive item(s). I'm thinking that the only other items I'll need to order before the ESC/motor combo is the servo, and the wheels/tires. Speaking of tires...I know, be in another thread (created by @Jerold ), you suggested GPR, and @LibertyMKiii recommended the GRP XM3. However, since I'm about to move to Vegas (where it's anything from "somewhat warmer", to "friggin hot", I'm wondering if the XM4 and/or XM5 versions might be better/smarter...say, XM4 during the 'colder' 6 months, and XM5 during the other 6 months (except for June-August, when I wouldn't be running the Limitless at all...WAAAAAY too hot).
I am in Texas and was running where road Temps were around 130 F. In the summer and I usually don't run below 40-50 F. In the winter. Been on the same XM3 set of tires all year (y)
No issues with soft tires in the heat and helps in the winter.

Those XB1 series mentioned above might he good too. There was this line of thought that harder compounds = higher speed handling but that is just not true.
 
Welcome to the dark side. I started with Traxxas as well and remember seeing you in the forums. The biggest difference is when you buy an Arrma almost everyone starts customizing everything on it right way. I don't know that there is any part of an Arrma that you cannot get after market or fabricate. Also this forum is great. Great people that no question unanswered. Everyone one is up for holding your beer while you try something new.

I'm a bit late to the party on this one, too many moving parts these days. Yup installing the nitro tubes are a PITA and a larger diameter would make it much easier. There is no reason (that I can think of) for it to be that tight. If I had to do again, I would spend less time building it to break the sound barrier and more time driving. I live in San Jose. We have way too many people and the roads suck pretty bad in most places.

Your paint scheme is awesome. It's asymmetric and helps you see which way the car is facing when it's down the road and just a little dot on the horizon. I ended up with the GTJ03-XB1. I figured the soft compound would give me a bit more grip and the weather is fairly cool in the area. They are kind of balanced.
First, thanks...I've always been a "dark side" fan (Vader rules). I also live in SJ...but, about to move to Vegas. Regarding the tires, yeah, for the SF Bay Area, those might be better...but, did the warmer (hotter?) Vegas weather, that's why I was thinking the '4' or (maybe) even the '5'.

It's too bad 702 Raceway recently closed (the only inside carpet track)...but, on the plus side, Eric bought all the track jumps, hills, etc, and it's now all at NorCal (including the wall ramp). As for the shocks, haven't started tuning them, yet, but I'll get there. Right now, working on obtaining/installing other upgrades (such as what arrived in the mail today...see below).

I am in Texas and was running where road Temps were around 130 F. In the summer and I usually don't run below 40-50 F. In the winter. Been on the same XM3 set of tires all year (y)
No issues with soft tires in the heat and helps in the winter.

Those XB1 series mentioned above might he good too. There was this line of thought that harder compounds = higher speed handling but that is just not true.

I wasn't thinking "harder compound = faster speed"...not at all. As I mentioned above, my 'thought' on the harder compound had to do with the higher temps of Vegas (where I'll be moving next month). In Vegas, road temps can easily exceed 130°F (especially in summer). It's never run the Limitless during the hottest months (June-Aug)...but, was figuring, the '5' could be used IF I ran in May and/or Sept. Oct, and into Nov, as well as Apr, the '4' might be better (not "hot", but definitely warmer than "warm"). From mid-Nov through Mar, the '3' would probably be perfect. Again, these are just my thoughts, based on no Limitless experience whatsoever. 🤙🏼

Now, I do have an upgrade update, as something "special" was found in my mailbox a short while ago. As some of you probably know, Kimberly Sanches (aka, the one & only BasherQueen) just released machined bulkheads for the Arrma 6S vehicles, complete with gaskets, and a CF plate. Unfortunately, the first batch (of, I believe, 40 units) is already sold out (they sold out within a couple hours...but, batch #2 should be ready for order placing next month)...but, for those lucky enough to have gotten one (or two), yet more yet received, here's what they look like.

20221022_125829.jpg
 
Have another "acquired parts" update - the beauty of what happens when Vitavon Racing & BasherQueen parts 'mate'.
20221023_124711.jpg

Arthur and Kimberly, both, do such incredible work. Sometimes, I think it's a 'shame' to even use their parts in RC vehicles, as they could be considered "works of art". As for the Scorched Parts parts, haven't received a 'shipped' notification (after all, it's still the weekend, even in the UK)...but, they have been ordered. Here's to hoping they arrive before I move (in 3wks).
 
Have another "acquired parts" update - the beauty of what happens when Vitavon Racing & BasherQueen parts 'mate'.
View attachment 251759
Arthur and Kimberly, both, do such incredible work. Sometimes, I think it's a 'shame' to even use their parts in RC vehicles, as they could be considered "works of art". As for the Scorched Parts parts, haven't received a 'shipped' notification (after all, it's still the weekend, even in the UK)...but, they have been ordered. Here's to hoping they arrive before I move (in 3wks).
Scorched can be a bit "off the ball" as it were when it comes to timely shipping. Fortunately they don't have a note at the top of their page currently stating that their behind on shipping so hopefully it won't take too long. In the past I've sometimes had to wait more than a week between when I ordered and when it got shipped.
 
Scorched can be a bit "off the ball" as it were when it comes to timely shipping. Fortunately they don't have a note at the top of their page currently stating that their behind on shipping so hopefully it won't take too long. In the past I've sometimes had to wait more than a week between when I ordered and when it got shipped.
I paid for "UPS Express" shipping, plus the order confirmation email does state "2-3 days for despatch" (notice 'despatch', instead of 'dispatch'...lol)...so, hopefully, the order is shipped within that time frame. Otherwise, what's the point in having parts extra for quicker shipping, and quicker delivery? As I mentioned, moving in 3wks, so need the package to be delivered approx a week before the move.

I'd like to get 'whatever' installed that I can before the move. Now that I have (at least, I think I have) all "Phase 1" upgrades parts for the front & rear, I should be able to get them installed before the move. If the Scorched order arrives quickly enough, I might even have enough time to install those (center section) parts before taking the rest of my RC stuff over to the Public Storage. There's still a LOT of stuff needing to be temporarily moved to Public Storage...and, I'll admit, I've been procrastinating. I should be working less in RC, and more on moving things out of the condo. Thankfully, I have "late starts" for work the next two days, so I can use those mornings & early afternoons to get stuff moved (that I should have already moved).
 
I paid for "UPS Express" shipping, plus the order confirmation email does state "2-3 days for despatch" (notice 'despatch', instead of 'dispatch'...lol)...so, hopefully, the order is shipped within that time frame. Otherwise, what's the point in having parts extra for quicker shipping, and quicker delivery? As I mentioned, moving in 3wks, so need the package to be delivered approx a week before the move.

I'd like to get 'whatever' installed that I can before the move. Now that I have (at least, I think I have) all "Phase 1" upgrades parts for the front & rear, I should be able to get them installed before the move. If the Scorched order arrives quickly enough, I might even have enough time to install those (center section) parts before taking the rest of my RC stuff over to the Public Storage. There's still a LOT of stuff needing to be temporarily moved to Public Storage...and, I'll admit, I've been procrastinating. I should be working less in RC, and more on moving things out of the condo. Thankfully, I have "late starts" for work the next two days, so I can use those mornings & early afternoons to get stuff moved (that I should have already moved).
Yeah. Fortunately, Scorched is better at engineering than proof reading. I've seen a lot of doozies on their website.

I feel ya...I'm a master procrastinator too. I hope everything goes off without a hitch in your move...or with a hitch...should you be using a trailer. :)
 
The 3rd screw on the Roto-Lok motor mount, and the 3rd & 4th screws on the EMP motor mount, aren't related to attaching the motor to the plate. As with almost all other motor mounting, motors are attached to both plates by only 2 screws. Well, except the Roto-Lok, which, evidently, does attach the motor to the motor plate via three M4 screws (can't remember if it's certain Tamiya it's Traxxas vehicles that attach motors the same way). The 3rd & 4th screws of the EMP is what I was referring to.

Specifically, I was referring to "holding strength" of the 4 (EMP) screws holding the motor plates to the motor mounts, compared to the 2 screws of the PPS (both have same essential design), compared to the 2 screws holding the curved piece of the Roto-Lok against the main motor mount piece. If all screws were in a straight line, then, yes, 4 screws (EMP) would have a stronger hold...but, the Roto-Lok mount is different. Although it uses 2 screws to hold the motor plate in place, those screws are not used to 'hold' the motor plate to the motor mount...instead, they are used to clamp a "third member" sort of piece to the main motor mount piece, which, in turn, also clamps motor plate between these two parts. In a way, it's similar to how the motor is held in place on the TLR 8ight-XE. Put another way, the 2 (PPS) & 4 (EMP) screws act more like giant "grub screws" to hold the motor plates against the motor mounts, essentially the same way a pinion gear is held in place on a motor's shaft, whereas the Roto-Lok uses a clamp method similar to how something is held between a vice grip. That's what the "which is stronger" question is related to. Hopefully, it makes more sense with me having worded it this way.

I'm a bit late to this discussion, and see things have pretty much worked themselves out. I did want to clarify the 3 screws on the PPS mount, as nobody has really nailed it. The top 2 screws do clamp the motor insert to the TOP of the frame, the same way the EMP's 4 screws do. The 3rd screw, or the "Adjuster" screw on the PPS mount is dual purpose.

First, it is what adjusts the mesh, and locks the mesh in place. The motor slide simply can't slide when that adjuster screw is set. I've seen people run only one screw on top, on crazy belt builds, and it's held fine. I certainly don't recommend it, but I support people's desire to experiment.

The second purpose of the "Adjuster Screw" is that it acts a "strap" of sorts. It is a steel reinforcement bolt that connects the insert to the main meat of the motor mount frame. If you follow the adjuster screw through the mount, it goes to where the motor mount frame is the beefiest. That screw has 219,000psi of tensile strength, and would hold about 2600lbs of axial force before budging. Holding the the mesh is no longer relying on the top motor mount screws. That force is being put on that steel screw, and it's trying to stretch or compress it, vs trying to slide or sheer the two top screws.

I say "strap" because the motor mount insert IS only bolted to the top of the frame. So without that adjuster screw, you could have 43 screws holding the insert to the top bar of the frame, and the top arm could still flex and spread open. Having the adjuster screw simply prevents that force from transferring through the top arm of the frame alone and straps it into the heart of the frame.
Both the EMP and Scorched mounts are nice. I would say it is all a personal preference as to what you buy. I think each system has their own benefits. When it comes to setting gear mesh, and mechanically locking it into place, the PPS mount is the only one that does that. If that adjuster is set, you could accidently leave your insert clamp screws loose and make a successful pass. You can't say that for any other mount.
 
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