I did 1.6's on my 100K engine(the old engine) and the valve float at low RPM's sucked. I took em off until I was ready to do the springs(the day after it blew, it was on the way to get some preprogramming for the cam)

 

1.6rr on a mild engine with stock springs (I'll change them when I do the cam) for about 10,000 miles, no problems. I noteced a lot of gain on the top end.

 

That's not necessary. You can remove a valve spring with the piston at TDC and the valve will only fall about 1/4 inch.