valve spring intsall. help

Okay, im installing a set of crower dual valve springs on my LS b18b motor and i need to take my stock ones out. How do i do it without taking the head off. the heads gonna stay in the car. I have the the valve spring compressor, but my main issue is with the valve's. once i pull the stock springs out, the valves might drop into the cylinder.
how do i go about take n out the springs while keep n the head on?

think... its reccommended that you take the head off / for ease of installation; if you want to do it the way you suggested = the head stays on, what i just thought of is ....

you should do a set at a time... have piston # 1 at tdc.... do those valves (they shouldnt fall, the piston is at tdc and the vavles will be sitting on them). then turn the crank and when # 2 is at tdc, then go on and continue down the line.

I just though of that and have no idea if it'll work or even makes sense. Like I said, the best way is to pull the head off.

yea i was think n about ur second method. alot of people told me about do n it that way. seems logical!
im also gonna fill the cylinder with compress air so that it will keep the valves in the head

we just got finished with some headwork on my buddies LS head and ran into a bunch of problems like this. taking the head completely off gets to be a bitch, and expensive if you dont watch what youre doing, goodluck with the project though...

so what problems did u run into? was the head still on the car?

he broke a timing belt and decided that it was time to do some upgrading. none of the valves were bent or anything, but when you take the head off youre talking new head studs, planing of the head (in his case the head was warped), new head gasket, few misc things im forgetting. things just add up, when i say problems thats all that im talking about is new parts here and there. really wasnt extremely difficult, just make sure you take your time and be patient.

Just was curious how did the head get warped?

the method ive heard people using was to put a bunch a rope through the sparkplug hole to keep the valves from dropping. But like the other guy said, i just took the head off my b16, but of course once i was in there, cams, valves, valve job, etc i just had to keep modding.