First post! my ultima project and questions

[RichieRich]

1. ive done a little research into my transmission options, but what i want to know is how well the car would be able to handle a brushless motor with the stock transmission (cleaned and properly lubed with proper bearings) ive been looking at the EZrun 13.5T 3000kv brushless motor and a 45a ESC, is this a good pairing? and will it play nice with the stock trans? and is the OT74 limiter gear something worth investing in? i know there are alternative transmissions (A&L and kyosho triumph to name a few) but i'm betting these are out of my range.

I think we've all agreed that the transmission should be able to handle a mild brushless system. The gears are pretty thick and should hold up to the abuse.

2. ive heard about the ultimas tendancy towards understeer, and having seen richieriches(correct me if i'm wrong) use of the lazer steering parts, will his setup work with a standard sized servo? am i correct in guessing he used the smaller one for battery clearance? the aluminum steering parts are pretty dang cheap on ebay, and since i was already planning on making some other parts out of aluminum (shock towers at the least, possibly top plate and more if i decide to give sand casting a shot) replicating that CF piece (seen here) in alu. should be easy enough

I actually used a lengthened chassis. So fitting a standard servo was no problem. Mikedealer used a shorty servo on his build to get a battery installed lengthwise. You've linked to a pic on that thread.

my basic idea with this car is to build it up well enough to make it hard to break, and to be 100% reversible if i decide i ever want to make a shelf queen out of it. its unlikely that it will ever be raced, but RC cars seem to be making a little bit of a comeback in my area, and a tricked out vintage car that can at least hang with the new guys would be fun

[vwjuice]

The limiter gear is definitely recommended for a 13.5T motor, I'm thinking of going that same route with my off-road Barney project Optima.

Sorry for being ignorant, but what is this limiter gear we're talking about here? I haven't heard of this before. I might want this to run in my Ultima's.

[Triton]

The limiter gear is definitely recommended for a 13.5T motor, I'm thinking of going that same route with my off-road Barney project Optima.

Sorry for being ignorant, but what is this limiter gear we're talking about here? I haven't heard of this before. I might want this to run in my Ultima's.

the limiter gear was a stock part in the turbo optima and salute, it works more or less like a slipper clutch. and Coelacanth i did read part of your CYANide thread, beautiful car! most of what you suggested is stuff i was thinking about doing, at present it just depends on how cheaply i can get most of this stuff for right now my budget is minimal so i'll be working on the cheap/free stuff to start with, expect to see an approximate parts list and cost breakdown in the near future. i'll get some more pictures of the car today so everybody can see what i'm working with

on the subject of price, you can find deals like this on any number of things if you go to garage sales auctions or flea markets on a somewhat regular basis, you would not believe some of the things my parents and myself have found! One time my dad bought an antique railroad timetable log book at an auction for 55$ it had timetables from the late 1800s up to the 1920s, we sold it on ebay for ~1500$ that sort of deal is few and far between, the latest thing they have been selling is dolls and bears, spent around 400$ on a TON of them at an auction and last i checked they have cleared $600+ profit on them, we're kinda like the american pickers guys but with auctions/garage sales/flea markets. and we're from iowa too! their shop is a couple hours northeast of us

[Coelacanth]

The limiter gear is definitely recommended for a 13.5T motor, I'm thinking of going that same route with my off-road Barney project Optima.

Sorry for being ignorant, but what is this limiter gear we're talking about here? I haven't heard of this before. I might want this to run in my Ultima's.

I started this thread a while ago, it's worth reading.

http://www.rc10talk.com/viewtopic.php?f=30&t=17162

[Triton]

questions round 2! ready? GO!

1. any specific suggestions for ball cups/turnbuckles? i'm looking for the lowest possible price and reasonable quality.
2. what are my suspension options, i've seen that 3racing has affordable options but what are the apropos sizes? i'm prepared to build my own shock towers in any event (deciding if i wanna make aluminum parts or lay up my own FG sheets between sheets of glass)
3. do you think its worth swapping the front to 12mm hex instead of 5mm tamiya. i figure its easier to get a set of 4 matching wheels and cut down the front ones rather than trying to scour ebay for matching wheels with different mounting styles opinions?

and thats all i can think of right now

[Coelacanth]

Here's a start. Get yourself a set each of these in your favorite color (many sellers have them in various colors):

http://cgi.ebay.ca/3racing-Sakura-Zero-4-8MM-Ball-Stud-L-10-10-pcs-Pink-/160582604311?pt=Radio_Control_Parts_Accessories&hash=item2563781617

And these:

http://cgi.ebay.ca/3-Racing-4-8MM-Hex-Ball-Stud-L-5-10-pcs-Purple-/150470708103?pt=Radio_Control_Parts_Accessories&hash=item2308c0cb87

And some ball cups to match:

http://cgi.ebay.ca/3-Racing-4-8mm-Ball-Cap-Tamiya-TT01-/150468296118?pt=Radio_Control_Parts_Accessories&hash=item23089bfdb6

As far as turnbuckles go, you'll want 3mm-threaded turnbuckles to fit those ball cup ends. You'll just need to measure your existing tie rods/linkages and find some the same length or a millimeter or two longer.

As far as shocks go, measure your shock lengths, extended, from the middle of the top hole to the middle of the bottom hole. I think I have 4 front Gold Ultima shocks but I'll need to match the specs. You're on your own for rears.

[Triton]

my problem is they dont exactly say the length of the shocks on the ebay listings so i'm not sure how to go about picking beyond asking the seller for measurements also does anybody have suggestions for the steering knuckle/front hub? am i correct in thinking the ST-15 parts will fit? i can see these parts potentially breaking because there is a lot of stress applied in that area, especially if jumping. and too keep this thread interesting here are some more pictures! the brass rod for my roll cage experiment, my work table (i do videogame related eletronics stuff among other things), and a picture of my remote and box

[Coelacanth]

I picked up this set for my Optima; they're pretty close to the Kyosho Gold shocks for the Optima. I think the Ultima could use these--I'm not too familiar with the Ultima, but the Optima needs the Turbo Optima taller shock towers to use these (or the Kyosho Golds). I'm pretty sure similar shock towers are available for the Ultima to be able to use the Kyosho Golds (or these 3racing units). At any rate, it's beneficial to know your shock lengths no matter which way you go. I can only speak for Turbo Optima shock specs.

I was able to reduce the length on these shocks by 4 or 5mm simply by inserting plastic spacers on the piston shafts before placing the shafts inside the shock bodies.

Looking forward to your custom roll-cage experiment!

http://cgi.ebay.ca/3Racing-Alum-Front-Rear-Damper-Kyosho-Lazer-ZX-5-/360366089000?pt=Radio_Control_Parts_Accessories&hash=item53e77e2328

[Coelacanth]

Here are some Kyosho Gold shock specs so you can compare with your shock sizes.

Front expanded hole-to-hole length: ~73 mm
Rear expanded hole-to-hole length: ~97 mm

Using spacers and different ball ends, you could probably figure on a workable length +/- 5mm of those specs.

As I said before, I could spare a set of fronts for $25 plus shipping, if you're interested. Kyosho Golds are probably the smoothest, best-performing shocks you could put on that Ultima.