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I believe it's possible to widen the Optima's rear stance with longer control arms, but does anybody know if shorter control arms exist, or tried something that worked? I'm thinking of something like the front arms I used from the Spider, which work with 43mm dog-bones (at least with my CYANide Optima). I could use the same-length dog-bones for the rear as with the front.

The control arms would need to have the same width on either end as the stock arms have, use the same suspension pins, rear hub carrier width, and keep the wheel in the same position (i.e. not alter the wheelbase). I wonder if the Spider rear arms would bolt onto the Optima?

Anybody have any ideas? It's times like this I wish I had boxes full of leftover parts...

The Spider rear arms should bolt right on to the Optima, since the first Spider was Optima-based! The original Spider used optima front and rear gearboxes with a different chassis (top deck is I think also the Optima MID SWB top deck), with the shorter Spider suspension to narrow the car to 200 mm.

Basicly the first EP Spider was an evolution of the Optima-based Scale Car/Oval cars (which were LWB Optima MIDs with a wide touring car body), from 235 mm wide to 200 mm wide.

Only from the Spider TF-2 onwards the chassis and gearboxes were different.

That's what I thought, thanks for the reply EvoRevo. If Spider rear arms will bolt right on without changing the wheelbase, I'm thinking about trying that out with my on-road project. It would look perfect with the rear wheel width the same as the fronts.

Anybody want to trade some rear Spider arms for some Optima arms or other parts?

Yup, that will work. I converted my mid few years ago using those arms. You can still use the stock optima rear hubs...since those work nicely with your wheels.

When you bought your front arms, didn't it come as a set for all 4?

highwayracer wrote:Yup, that will work. I converted my mid few years ago using those arms. You can still use the stock optima rear hubs...since those work nicely with your wheels.

When you bought your front arms, didn't it come as a set for all 4?

I received a set of front arms in a trade with someone here, and I bought another 2 sets of fronts-only on eBay. I'd like to upgrade the stock Optima rear hubs with alloy ones, of course. I have plenty of stock glass-filled nylon ones.

Ideally, I'd like alloy front & rear control arms & hubs/C-carriers. That would totally []D [] []V[] []D the build.

id like some of them c hubs as well for this beast...


and maybe a fat rope chain LOL

If the rear suspension is similar to the Ultima's, you could easily adapt RC10DS rear arms w/minimal mods*....but you'll have to either custom make dog bones, or find a set of drive axles that are narrow enough..
*bonus: the wheelbase will be adjustable too.

Diggley wrote:If the rear suspension is similar to the Ultima's, you could easily adapt RC10DS rear arms w/minimal mods*....but you'll have to either custom make dog bones, or find a set of drive axles that are narrow enough..
*bonus: the wheelbase will be adjustable too.

Unfortunately they're different. Ultima rear control arms are much wider at the base.

bdrmbully wrote:id like some of them c hubs as well for this beast...


and maybe a fat rope chain LOL

Cross made tons of hop-ups for the TF-2 and GP Spider/GP-10 in (light) gold. They'll be hard to find, but they were available in the USA in the mid- to late '90s.

For the c-hubs, you'd want one of the following parts:

AA-139GP Al.hub carrier set 4-degree for GP10,PURE10 3,400yen
AA-140GP Al. hub carrier set 8-degree for GP10,PURE10 3,400yen
AA-142GP Al. hub carrier set for GP10,PURE10 3,400yen

(list pulled off the Cross R/C site through the wayback machine at the Internet Archive)

bdrmbully wrote:id like some of them c hubs as well for this beast...


and maybe a fat rope chain LOL

I have a pair of those tech racing t'buckles perfect for the rear of that TO.
I'll think of something to ask for trade.

Okay--at least for the CYANide Optima, I'm probably going to scrap the idea to install shorter rear control arms as nothing out there lends itself to an easy swap. The Spider rears are almost a centimeter less wide at the hinge-pin end as the Optima arms, and are quite a bit TOO short...about 18 or 19mm shorter, each, than the Optima arms. I'd still dig some alloy rear hub carriers, though.

I think a few options exist for front alloy arms & C-carriers, as some of you have pointed out, Spider/TF2/TF3 arms and carriers should work, and will be quite close to what I've already installed on the CYANide car.

you mean something like this ?

treehugger wrote:

you mean something like this ?

Exactly! Nice goodies there, Paul.

One thing I've learned is that the Spider/TF2/TF3 rear arms won't work to replace the Optima rears, as they're much too short (about 19 mm shorter than the Optima arm) and too narrow at the frame-rail end. The Optima arms are almost 4mm wider.

The fronts would work great, however.

kyosho sells shims in the range of 1 to 4 mm thicknes.
Should make the rear arms fit.

mvh Isobarik

treehugger wrote:

you mean something like this ?

show off ?:@P trade for them c hubs lol