Citroën ZX Optima Mid LWB Rally

[j0pp3]

After all the restoration projects almost finished I've come up with the idea of creating an Optima Mid rally car. A big reason for this particular combo is that I've got an original Kyosho Citroën ZX body unpainted and with N.I.P scale accessories. It's from a rally series based on the Raider chassis from around 1991. It just happened to have the same wheelbase as an Optima Mid LWB. I've started doing some custom work, copying an original aluminum LWB chassis to create an FRP version. This also means I will create FRP towers, top deck etc. The towers will have a slight change in the design to make it more unique.

More to come soon!

[j0pp3]

Update! So.. a few days later and a lot of cutting in FRP with the Dremel. I took an original aluminum LWB chassis and traced it. Kind of happy with the result. It almost looks like a Mid Custom Special chassis. This will be the sturdy base for my rally car. Next on the list is to craft some shock towers in the same material.

[j0pp3]

Got some proper wheels and tires for this project. OT-90 together with W5053 looks amazing

[alcyon]

and i thought i was an Optima Mid fanatic !

[j0pp3]

Haha, the Optimaniac bug is the best bug ever to be bitten by

Now early morning with rain outside. First time raining in 5-6 months back. At least the last spots of snow will melt. Unfortunately that means no crafting parts today.

To be continued...

[isobarik]

Originally Posted by j0pp3

Haha, the Optimaniac bug is the best bug ever to be bitten by

Now early morning with rain outside. First time raining in 5-6 months back. At least the last spots of snow will melt. Unfortunately that means no crafting parts today.

To be continued...

Nja was in "fjollträsk" yesterday and it rained atleast it "duggade" when i was going from the hotel to centralbadet.

A friend of mine btd drove an ultima topped of with an peugeot think it was an 405 but not sure always wanted to make an replica but havent found an good chassi for it.

nice thread btw.

mvh isobarik

[HKS_TRD]

Those wheels and tyres look damn hot

[j0pp3]

Iso, I remember a friend got the Peugeot 405 when I was a kid. I think that car had the same wheel/tire setup I have found for this project.

Thanks HKS_TRD!

Let's have an update!

First out, I found some original scale parts (Kyosho SI-12) for the body a while ago. Kind of rare stuff.




Then some build progress. Went through the Optima pile and found some good gears and a belt. The white center gear is probably a Thorp 5022. Got it with a donor car and it feels tough! Standard gear differentials all around. Took a classic see-through-photo of the drive train.

[j0pp3]

Sunny weather in Stockholm today so I got a few parts done with the Dremel. Optima mid front tower and a Slingshot rear tower plus front/rear suspension plates. I'm not sure a Slingshot tower will work as I want but I want to try it. The Optima Mid tower I used as a template was modified with extra holes that don't even line up but I didn't realize that until the tower was finished... Right now it's no big deal as I will try different shock setups anyway.

[j0pp3]

Another update. After some testing I decided to use the slingshot tower in the front instead. It makes it possible to get a good suspension geometry with shocks laying down. It is also a bit lower than the standard Mid tower which may help with body positioning later on. Don't worry, I will fix the negative camber angle. The front suspension plate seems to work fine.

[j0pp3]

Got some more time spent on this project!

I ignored my first idea of having short shocks in the rear as the long shocks gets a better mounting position after all. As in the front, the rear shocks are mounted in the hubs and I found out that they can be mounted in the gearbox if they are fitted behind the wishbones. As you may suspect the rear hubs are placed backwards.

Rushed it a bit and just had to try the wheels on even if the car lacks rear turnbuckles and dog bones all around

Next on the list is to craft a matching top deck.

[Crashtest33]

Hi Joel.

You don't have a set of calipers do you? Any chance you could take some measurements of OT-88.
I want to CNC the plates as I can't get any.

Cheers
Nick

[j0pp3]

Originally Posted by Crashtest33

Hi Joel.

You don't have a set of calipers do you? Any chance you could take some measurements of OT-88.
I want to CNC the plates as I can't get any.

Cheers
Nick

Hi Nick,

I'm not sure I have the right tools to measure all the details. The inner plate have a diameter of 20mm and is 3mm thick but is flat on one side and coned on the other. The hole is also coned to fit the axle. The outer plate is 20mm in diameter and around 1mm thick with a rectangular hole to fit the axle. I'm not very good at this...


Hey, what about this german auction?
http://www.ebay.de/itm/Kyosho-OT88-E...item51ab745e45

[j0pp3]

Some more parts made. You might ask why I chose to copy a Rear Plate (L) adapted for a mechanical speed control and the answer is that I only have that version in metal. I prefer copying metal parts because it's so much easier to follow the contour without hurting the original part too much



Next update will show an almost complete roller!

See ya soon...

[Crashtest33]

Originally Posted by j0pp3

Hi Nick,

Hey, what about this german auction?
http://www.ebay.de/itm/Kyosho-OT88-E...item51ab745e45

Cheers pal.
All purchaced. Build starts soon.

[j0pp3]

Some changes again...

As I'm using the sports shocks that were often seen on less fancy models I took the decision to continue using "sports parts" for this build (they also have to be used eventually). I replaced the adjustable turnbuckles with plain rods and also kept the Rear Plate (L) design meant for a mechanical speed control. I have also tested using a standard shock tower in the rear but made some custom holes for shock mounts. Maybe the standard shock mounts can be used for mounting the body. The front shocks have been relocated to holes one level below. After I took the pics I realized I need to adjust the camber angles again... damn rods!

Picture time!

[j0pp3]

Slow but steady progress. Bought a new built Ferrari F40 as donor car. Now I have a bumper that will soon be transfered to the rally car


A picture showing how the donor car arrived. The motor is a Mega Outlaw 22x1. I might steel some more parts like the belt protection as no glue or tape was used by the unknown builder. I have now a second set of onroad tires!

[timmy]

Hi Joel,

Don't suppose the donor car came with a manual did it? Or if anyone on here can point me in the right direction for an f40 manual/parts list.... Trying to find part no's for the none mid custom parts - body mounts, bumper, wheels and tyres etc..
cheers

[keithrc]

Timmy, try Fireboy125 (Chris) on ebay, I got all the things needed for an F40 conversion from him so he might be able to help if Joel can't.

BTW Joel, this reminded me of the F40 front shock tower I asked about, do you still have it?


Keith