I just finished installing the roller springs in my AFR heads. They are AFR 8000 springs.
I set them up at 1.95" installed height, which according to my calculations will give 212lbs on the seat. Actual measurements with a spring checker says 225lbs.
It's real hard to nail the installed height within .010". I had .060, .055, and .015" shims available. The .055" shims were the original AFR shims.
As I did this, I decided to err on the low side rather than the high side when making the measurements. That is to say, I err'ed on the side with a bit more pressure than less.

Is this the standard way of doing this?
Shims don't seem to come in increments less than .015".
Another thing, the AFR heads are cut for 1.625" springs. This leaves a lot of room at the bottom of the spring when you use 1.550" springs, which is what I used. Seems to me it would be nice to have a spring cup that captures the bottom of the spring, but AFR shipped the heads w/o any sort of spring cup. (I ordered them initially with flat tappet springs then changed to a roller, AFR swapped me springs free of charge)

Anyway, just curious about this stuff....as usual.

Ron