I was sleeping but then...
I knew I was needed!!!
I am indeed very well informed about Kyosho Optima and Optima Mid platforms.
The answer to your question is the differences are far too vast and you need to buy one of each!!! Maybe a few!!!
Ok, maybe not right away, but I bet you'll love the first one so much, you'll buy another! Kyosho makes GREAT buggies!!!
The two cars share a few common parts but the Optima, Jav, Turbo Optima and Optima Pro Gold chassis are pretty different from the Optima Mid, Turbo Mid and Mid SE chassis.
The biggest difference is the location of the motor on the chassis.
OG Optima have rear mounted motors. They hang right off the back of the car actually.
Mid's motors are mounted in front of the rear axle.
Idea was that as carpet racing became more popular, the Mid weight distribution gave better handling characteristics on those surfaces.
The rear motor puts lots of weight over the rear axle and tires. This is generally better for dirt track traction and handling.
I believe all the rear motor chassis were 258mm wheelbase. Mids were availible with 258mm and 270mm options.
Longer wheelbase tended to improve high speed stability with a bit of cost, not as quick around corners like SWB cars.
There are also different shock options that came with different models.
The original cars had red shocks that I think were 10mm pistons. I am not 100% sure. I don't own any of the red shock Optimas.
There were 12mm gold shocks. They are my favorite RC shock ever.
I restored a set with Xrings, titanium shafts and new silicone oil. They are like silk! So smooth!!!
Titanium shocks are pretty to look at. They work well enough but the rate adjustability feature isn't great. I never use it.
They function well but I am terrified to break them. Parts are rare for titanium shocks. I would not race them regularly for that reason.
New rerelease red shocks are 12mm and use a slip collar to adjust the spring preload.
New (re-re) offer gold and gunmetal bodies but are the same shocks otherwise. I have a set of each and am waiting to build and install still.
I hear the rere shocks are every bit as good, even better than the originals. Ppl really like the new style threaded spring adjust collars vs the og slip collars. Much easier to adjust.
The original Optima ran a chain drive. A belt drive upgrade was availible for it.
I believe the rerelease cars offer similar options.
The original Mid ran a deeper tooth belt than the new one too.
Do you intend to run the actual 1987 car or a rerelease version? Theres a lot of differences between new and old.
Are you looking to keep with Kyosho for electronics?
The Lemans 240 13.5 motor will have plenty of power as should most other 13.5.
13.5 turn motors are commonly the limit for 1/10 4x4 at the track.
The Lemans 240 esc will fit into a Mid chassis nicely (I hear).
I currently own a HobbyWing XR10 Legends esc for my Mid intended for the track.
I have a few different motors to pick from. 10.5 Yokomo titanium drift motor is likely the fastest.
I'll report back one day I hope!
I haven't been to the track in a VERY long time so keep in mind that a fair amount of my on-track knowledge of these cars is very dated.
I know a LOT about these cars and 1/10 scale vintage Kyosho generally.
I think I have 5 Mids and 2 rear motor Optimas currently, tho only 1 is close to rebuilt now.
From left upper, counter clockwise:
Theres a LWB alum chassis, the SWB carbon fiber car, the OG LWB JG graphite chassis car that I raced in the 80's, finally a SWB 3mm alum chassis Optima Mid SE.
I can talk about these cars for days so ask away!!!
