sn8ke eatr

alright like it says, the heads are on the motor and i need to replace the springs.

i know i have to use an air compressor with about 60 ( right?) psi and with an adapter thread it into the spark plug hole.

my question is if each cylinder is at tdc.. do i still need to do the air thing? how far down does the valve fall and can it be retrieved with a magnet?

SS RRR

don't have to use a compressor. i've found using rope much easier and faster. get a length of nylon rope and stuff the cylinder, turn the crank until the piston crushes the rope. just make sure to keep the valves nearly closed (don't push down on the tips) so the rope doesn't get tangled on them.

sn8ke eatr

hmm that dosent sound like a terrible idea.. whered you get that from?

SS RRR

Any hardware store. I'm not sure how many other types of rope there is that you can buy new, but just use nylon rope so no particles end up in the cylinders. I usually get the piston close to BDC and stuff a few feet in the cylinders. Make sure it's a small enough dia. to fit into the spark plug holes.

shoebox

If you don't use anything at all, the valves will not be able to fall far enough to go anywhere when the piston is at TDC.

Don 97 SS

As always, Shoebox is right. I use the method that Shoebox references (I don't recall its name or have a link for you). I think it is much easier. With my (94-95 design) SLP headers I have a really difficult time changing plugs, yet alone, stuffing rope into the plug hole. Using my long necked 3/4" wrench with a socket for the crank, I am able to rotate the crank (by leaning over the radiator at the front/top of the engine with the wrench handle positioned in front of the TB) and visually position each cylinder's valves to when they are at TDC.

mnypitTA

You can do the TDC method, but it is kinda a pain to figure out exactly when each piston is completely up. We just did this, but we had the oil pan off and could see up inside. With the rope method you can feel when it hits the top because it will stop moving. After we did 2 with the TDC method we gave up and just pumped air in the rest. That worked fine and was a hell of a lot easier and safer.

The Engineer

Also, Crane makes the best heads-on spring compressor. With this tool you can do two springs at a time and it works well under the 4th Gen F-Body windshield cowling for the rear cylinders (#5, 7, 6 & 8).

WD

SS RRR

I never had luck w/ the TDC method. I tried it with a piston I knew was at TDC and the valve would fall too far into the relief keeping the locks from being loose enough to take out.

Javier97Z28

I've used the TDC method a bunch of times on a bunch of different cars.. the valve seal tends to hold it up enough to get the job done.

The Engineer

The TDC method works well for me on my LTX engines, I used it this past weekend again. I'm done with the spring and retainer change.

WD