OPTIMA----for racing

[Soncho Ponza]

starting an optima for racing. I need to start a nother build like i need a whole in my head . i have a sprinter, 10t, team car, SC10t, edinger, and 2 buggies for the boyz. All projects started and not finished, but HEY lets start another
Couple questions for those out there. did the optima have a ball diff option with the chain drive. is the belt drive conversion similar to the mid or lazer meaning the balls diff rings size of rear unit , and did the MID have the same belt teeth as the lazer, and even up to the belt teeth of todays zx-5.

[adam lancia]

starting an optima for racing. I need to start a nother build like i need a whole in my head . i have a sprinter, 10t, team car, SC10t, edinger, and 2 buggies for the boyz. All projects started and not finished, but HEY lets start another
Couple questions for those out there. did the optima have a ball diff option with the chain drive. is the belt drive conversion similar to the mid or lazer meaning the balls diff rings size of rear unit , and did the MID have the same belt teeth as the lazer, and even up to the belt teeth of todays zx-5.

1. Pretty sure a ball diff was an option, but not positive.

2. Diff size should be the same.

3. Mid and Lazer have different belt tooth pitches, Lazer uses a finer tooth than the Mid.

[Mr. ED]

chain drive diffs were all geared, but if you go belt converion you can put ball diffs of the top of line mid series. The optima belt conversion uses the SWB mid belt.
(One member here constructed balldiffs for his chaindriven optima)

[Soncho Ponza]

thanks ED ya i pulled apart an extra Mid last night i had around, and streched next to the chain it looked like what u said on size . belt would probably be the easiest. The chain mod would be cool for the "what the hell are u runnung look" im sure the belt would hold up longer too but that chain is just so damn cool and vintage. what was the build with the chain mod was it hard and has it held up. I have a bunch of ideas in my head but i don't want to cut something thats hard to replace. I saw a post back that metioned newer replacement belts from a source other than rc or ebay whay was it .

[ROH73]

If you decide to stay with the chain, there was a one-way front diff available with sprockets on it. I don't know the p/n, but I have it in one of my Turbo Optimas and it really changes the handling characteristics of the car.

Regards,

Robert

[Soncho Ponza]

The other reason for staying chain is it would be easy to increase the wb by adding some chains or if their is an outlet for the long wb mid belt out there.

[Soncho Ponza]

Does anyone know the # for the one way front on mid. was it an option house part.

[Mr. ED]

I don't think it is an option house part.
I have one installed in my lazer since yesterday and I think another one somewhere for my mid. but both came to me used and withut indication on the origin. I'll see if I can make a picture.

kyosho fan made those chain ball-diffs and the procedure included glueing. Search his recent posts and you'll find it. I guess it is is ok or not depending on how well you do it and what you put it up against. since you have no slipper the gearbox can be put under a load of stress.

Chains are not my thing: they don't break but you have to maintain the tension regularly

[highwayracer]

There was a one way diff made by option house but it came with the plastic for the belt vs. the chain. You just need to take the internals out and put them in the chain plastic. At the time, they already had the belt drive option for the optimas, so they packaged the one way with the belt pulleys.

Parma also made a one way diff conversion for the optima....but you had to put it together. It came with 2 one way bearings that had to be pushed into an aluminum barrel. The kit also came with the out drive axles that inserted into the one way bearings.

The orignal optima worked best with the one way in front and the gear diff in the rear. The mid worked best with ball diffs all the way around.

Regards,
highwayracer

[Soncho Ponza]

Did any of the manuals have the parts numbers listed, or did any of them come with the oneway stock . sometimes u get better search with part numers on ebay,--- sometimes

[ROH73]

I did some digging and my 1988 Kyosho Mini catalog shows the "One way clutch" with p/n W-0106.

Regards,

Robert

[Soncho Ponza]

Thats great thanks for the info.

[adam lancia]

If you decide to stay with the chain, there was a one-way front diff available with sprockets on it. I don't know the p/n, but I have it in one of my Turbo Optimas and it really changes the handling characteristics of the car.

Regards,

Robert

Are these the ones you're thinking of? The purple one is, I think, an HPI/Hot bodies part but the other 2 with the chain sprockets I picked up at my used to be local hobby store where I went to university. I would be willing to bet they've got a bunch more there, if you want their contact info drop me a PM and I'll get you hooked up.

[Soncho Ponza]

OOOOOOHHH YYYYYAAAAAA That is some EYE CANDY. PM sent i hope their still is some around thanks for picture..

[Mr. ED]

From the description it sounds like I have the Parma version one-ways.
I also have the solid axle option from kyosho, never really figured out what to use that for.