As the title suggests this is a build project of a Kyosho Scorpion conversion to 4 wheel drive .
Aims
1 period possible with 1980's tech/parts
2 to keep it looking like a Scorpion cosmetically
3 to be functional ,not a shelf Queen
The plan is to use chain drive from the rear to the front , Optima front steering hubs and a front diff .
I've started by making a replacement for the front steering hub king pin , as standard the king pin passes through the steering hub but if fitting a driven hub I had to think of an alternative system . My solution is to have a king pin under the hub that passes through twin flanged bearings fitted it the pin that passes through the front suspension arm .
The first issue I've come across is that with a wheel fitted to test it's increased the front track to make the front wheel 10mm wider both sides than the back so I'm going to have to find ways to bring it in again , I think I can move each wheel 6mm inward so I've got another 4mm to go .
Here's pictures of the king pin arrangement and Optima steering hub installed .
this is a comparison of the stock steering hub and king pin next to the Optima hub and king pin .
hub installed
and view from front showing increased track .
there's surprisingly little slop ,at least comparable if not better than the stock king pin setup , hopefully the tiny flanged bearings don't wear out too quickly.