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Ok guys, I finally took the time to put my plans into action. My goal was to use the Nix91 platform as a foundation but retrofit some of the newer hardware from the B5. As much as I wanted to keep the Nix91 arms, they interfered too much with the wheelbase since the B5 hex wheels have a different offset that threw off the width of the car too much. The main reason for doing this was due to the fact I already maintain a healthy supply of wheels and tires in different treads and compounds for my B5 and B5M.

I ended up machining a new set of arms for the car from nylon 6/6. These are not glass filled arms like Kyosho uses so they will probably be an inferior product..... .

The front arms were lengthened 2.18mm per side and the rear arms were lengthened 4.88mm per side. While I was machining new arms I also had to modify the arms to accept the B5 hubs and carriers. Not much was needed and it ended up being straight forward.

Both shock towers were modified significantly and actually reduced in height a good amount. The front shock tower alone was shortened 14mm. Mounting the big bore shocks was a breeze and was actually easier to do on this car vs trying to install big bores on a standard RC10.

I also used the turnbuckles from the B5 kit which worked perfect.

The car shares the exact wheelbase and width as the B5. Using some of Slotcarrod's measurements, I was able to get rid of the bump steer, which required a bit more work since I had changed a few things with the front end.

I hope to get the car on the track tomorrow for some testing. Time to heat up the solder iron so I can get my electronics installed.

Jake

Lookin awesome Jake!

Absolutely fabulous.

Just out out of interest: why does the NIX have this assymetrical design for the front end of the top plate?

One word: BADASS! You certainly took it to the next level, really well done Jake. Will you also sell these new parts as an upgrade kit? Keep up the awesome work.

Mr. ED wrote: Just out out of interest: why does the NIX have this assymetrical design for the front end of the top plate?

One reason

1. The original 91 Stealth car had an asymmetrical top deck due to the use of an oversized servo saver on the right side of the steering cranks. the top deck had to be designed around the large spring and nut that protruded up above the top deck.

The Nix91 was a replica so we copied it as close as possible.

I just got my electronics mounted and it took a while to get the servo in where I got full throw left to right. The area to mount a servo is super tight for a full size servo and it requires a bit of thought to get it mounted just right.

I need to do some testing with the car to make sure the parts hold up as well as not make the car difficult to drive. Sometimes drastic changes can really change the behavior of a car. I am hoping that the car drives similar to the B5 but I doubt it. The rigidity of the chassis with the upper deck may make the car super twitchy on our high bite track. I plan on running a pack without the top deck as well to see how it changes the characteristics of the car.

The good news is I have all the CAD files for the new parts on this car

Still have plans to run a few packs through the car tomorrow. I will attempt to have my youngest video but last time I did that, it was impossible to watch

Jake

You were saying about the arms?

Great looking buggy, the track report is going to be interesting.

nice work jake!

This is fantastic!!!

Looks great!

Very nice Jake!

Did you give any thought on using the NIX62524 bell cranks and mount the sideways? It would give it a more modern look IMO. I remember a mention of an asymmetrical top plate, maybe that played a role in it.

There it is! Nice!

To get a bit more flex and less twitchy, something we do in TC is remove some of the top plate screws on the posts. You will still be rigid front to back but allow some side flex. The bad thing with this, is now you risk damaging the chassis and top plate in a bad crash.

Hi Jake,
That's a super cool looking car. I guessed right most of your upgrades but B5 wheels and hubs were surprises for me

-Niki-

that's just AWESOME!!

Well the track report is not going to be a good one.....

I got to the track and was the only person there...perfect. Started track maintenance since they raced last night. Was working the track when the three guys who own the place came back in the back and started talking my ears off. Finished track maintenance while the owners sat and watched while talking to me. Start prepping the car for the first run, still having my ears talked off. Finally after an hour of being at the track, the owners go back to the front and I finally have peace where I can run the car and do what I need to do.

No sooner than I set the car on the track, the doors open and about 25 screaming kids walk into the track area for a birthday party. They start going through my pit, including the parents. I have to pull the car, I go over to the pit and kindly ask the mom to remove her purse which is laying on top of my tool box. I gather up my stuff and stow it away so nothing walks off without me knowing and get back on the track while I still can.

Run about half a pack and pull the car for tire changes, minor adjustments, etc. Now I have the kids and parents talking my ears off. I decide to wait to put the car back on the track and sit and babysit my pit since all the heathens are running around. The birthday party starts and I watch as the track is utterly destroyed by 20 plus kids who rented short buses.

The party ends 2 hours later and the track is destroyed beyond the time I want to invest in fixing it. I throw the car on the track and slowly navigate the course to find any new potholes. As I am driving the rear is extremely loose from all the loose dirt on the track surface. During my slow laps I occasionally bump the throttle to make the hand full of doubles. As I am getting ready to pull the car I decide to attempt to double on last time on bringing the car to me. The rear end slides out on the ramp and the car gets sideways in the air. As it hits the ground I hear the distinct sound that break parts make, super loud crack. Walk over to the car flip it over to see the rear shock tower has snapped in two. UGH!!!!!

Overall impression of the car - Super unpredictable

The car was extremely twitchy and was really difficult to drive fast. To compare (Rod you will like this), my B5 is kind of like a 450 motocross bike. It is super easy to ride and you can be lazy with it, getting in the throttle as you need it. If you lay into the throttle, it will go and feel planted everywhere you point it. My version of the NIX91 was similar to 2 Stoke. I felt uncomfortable and felt like I was on pins and needles the entire time (those who haven't ridden 2 stokes, you have to maintain super high rpms through your corners so the bike will shoot out, 4 strokes you can roll through the corner with easy then lay on the throttle and torque kicks in and away you go).

Another issue I found is I don't get full servo throw left VS right. I noticed it on the bench but was so minor I didn't bother with it. On the track my turning radius was cut in half left VS right. I need to find a better way to mount the servo so I can get the throw I need. The problem is the steering bell crank hits on the front of the servo before the front wheels fully lock.

Never in a million years did I think this car would bottom out. I kept slapping the chassis everywhere, shock tuning is in short order.

I did get to compare three battery configurations, full stick pack, shorty (rear) and shorty front. The care really tamed down a lot after getting rid of the full stick pack. The shorty pack moved forward felt better than running toward the rear. I have a feeling has everything to do with my piston and shock oil configuration in the rear. There was no way I was going to try to change oil today. Hell when I was changing tires I had parents and kids saying, "So what are you doing huh, oh you're tuning your car up!"

Ran an 8.5 with 8 degree end bell timing and it ran flawless. Diff started barking just a tad which I have seen frequently with the original Stealth tranny. I prefer to have my diff work smooth so I take my time to get is set properly.

slotcarrod wrote:There it is! Nice!

To get a bit more flex and less twitchy, something we do in TC is remove some of the top plate screws on the posts. You will still be rigid front to back but allow some side flex. The bad thing with this, is now you risk damaging the chassis and top plate in a bad crash.

Rod I am thinking about making a top deck out of kydex which will give me some flexibility in the chassis.