Rear coil over thoughts...

[Sweeps]

I'm in the process of preparing my car and i'm working on the rear suspension.

I intend to run coil overs on the rear of my car.

Ok guys here's my thoughts.

The KYB dampers that came off it were;

22 inches open from bush eye to plate at the base of the pin

13 inches closed at the same point.

9 inches of travel (Not rocket science i know)

I'm assuming that they are replacement dampers ie the same length as standard.

So to my question, if i were to replace these with coil overs that measure;

20 inches open

12 1/2 closed

7 1/2 inches of travel

Thats with 2 inch Diameter Body with 16mm Rod and Bearing

Now i realise that they are 2 inches shorter but i intend to lower the car by the min of 40mm anyway, so when the springs compress the damper will be in or around its optimum position.

Have i got that right?

Does that make sense?

What are your thoughts on spring rates and what to use?

I've read that for drifting/road use 8kg fr and 6kg rear, then in another article 6kg and 4kg, shall i go in the middle?

The car will be used as a weekend run about and some times for drifting.

Your thoughts and suggestions please?

Mark