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Hi all, just acquired an optima (chain drive) well its on its way ! So will post pics when its driven here, what I need to get what I know of are driveshafts what fits cvd, uj, ? And how can I convert to 48 dp on spur gear, been a long time since I played with optima, (I forgot) cheers guys have a good one.

Search for Robinson, tufnol and perhaps Thorp.

Be warned, prices are a bit high

Looking foreward to seeing some pictures.

I believe Kyosho made 62.5mm U-joints that were perfect for upgrading the Optima's dogbones, W-5061. You can also still find Kyosho CVDs with 62.5mm bones, KYOUM522, but they have 5mm straight axles with cross-pins to secure the wheels with 12mm hexes, unlike the tapered-hole hexes used by the Optima series. Those can be pretty expensive and will require you to find wheels meant for 5mm axles; or drill out the axle holes on vintage wheels to fit them (vintage wheels only have a 4mm outer hole so new Lazer CVD axles won't fit without reaming them open).

65mm and 68mm Lazer CVDs are dirt-cheap as aftermarket companies like 3Racing make them, but they will require longer control arms and camber links. If you go that route, you end up modernizing your Optima quite a tad, maybe not something you're planning on undertaking. The easiest option is to stick with the stock dogbones, which are very common and usually cheap. The next easiest option is to be patient on eBay and hope you can find a cheap set of W-5061...which won't be easy. The most complex option, going with CVDs involves a fair bit of resto-modding, something I did with most of my cars: CYANide, Barney & OptiMutt.

Wicked, thanks for that, quite like the sound of modernizing it, so I would need arms and carriers as per " Barney" that then makes shafts "easier" , would like post pics but can't download so it will have to wait for arrival, cheers all. Take care.

al.48 wrote:Wicked, thanks for that, quite like the sound of modernizing it, so I would need arms and carriers as per " Barney" that then makes shafts "easier" , would like post pics but can't download so it will have to wait for arrival, cheers all. Take care.

The rear alloy arms are a pretty easy mod, they're on eBay and are probably cheaper than a nice set of original arms. They're exactly 5mm longer than stock arms so 68mm Lazer CVDs are a perfect fit. You can use the stock rear carriers. The aluminum arms are an almost perfect swap-in for the stock arms but you'll need some spacers to eliminate slop for the carriers. I have an assortment of aluminum spacers with 3mm holes in various widths, they're cheap too. About the only thing you really need to modify is drilling holes in the back of the arms to mount the rear stabilizer and getting a set of modern 12mm hexes with cross-pins to mount wheels...and you'll be able to run any modern 12mm hex wheels, provided they have enough negative offset.

The fronts aren't that easy, mind you.

Thanks for that, can I not use lazer front and rear ? arms and hubs, cheers. Have a good one.

I think you can use Lazer front arms but I haven't done this with any of my cars. Keep in mind that Lazer arms are very long compared to normal Optima arms; widening your front track that much on a relatively short wheelbase chassis will probably make the steering super-twitchy and unpredictable. I think Lazers use minimum 73mm CVDs in the front, compared to the Optima's 62.5mm. That's a full 2 cm wider track than stock. Maybe someone else here has tried that combo on a comparably short wheelbase Optima and can comment on the handling characteristics?

With everything I have read zx5 rear shafts are 65.5 mm long so am I in with a chance ? What does everyone think about this : zx5 arms carriers hubs etc hopefully zx5 driveshafts, carbon fiber shock towers, topdeck, and motor guard, large bore shockers ( not sure what make yet) opinions everyone, cheers all, have a good one.

What rear diff can I use for belt ? Can't find a mid rear diff anywhere found belt and front diff no rear, help !! Cheers all. Anyone know if laser diffs are the same ?

Can I use sg-25 for front and rear diffs to get belt drive ? Cheers all, have a good one.

al.48 wrote:Can I use sg-25 for front and rear diffs to get belt drive ? Cheers all, have a good one.

Yes...but you'll find the rear diff is becoming a very expensive part these days. Just the rear diff alone will set you back close to $50 and up. Crazy prices! It's almost a better idea to find an Optima Mid parts car.

Can you not use half optima diff with sg25??

Getting excited !! Should be here in day or two

Belt ordered ! Plus two sg25 diffs, all sorted !! All I need is the postman now !

al.48 wrote:Can you not use half optima diff with sg25??

No...but you might've figured that out already.