More (stupid?) engine build questions (Oil Relief Valves).

So im still building and learning which is good. But the other night i got to the 1600 dual oil relief bit and i couldnt find the springs etc to go with them so i went out and grabbed one of those EMPI (I know but no one else seems to make them) http://www2.cip1.com/ProductDetails.asp?ProductCode=ACC-C10-5326

Which was all good, but i was told that you dont want to put one of those pistons with the groove into a dual relief case.

But first issue was that the long spring with the new piston on it seemed a tad too long:


And tonight i found the original springs and pistons and this is what i saw...



Should i just cleanup & reuse the old ones?
Should i just use the nice shiny new pistons and old springs? Or are the springs fine and shrink from the pressure over time?

Also if it is ok to use the piston with the groove in it does it go onto the big spring or the little spring?

And one final question do the gasket kits come with the metal gaskets for the screws you secure these springs and pistons in with, because i have bought two lots and neither appear to come with the gaskets, can i just use the old metal gasket with a little bit of permatex on them?

As per normal thanks everyone for all your help.

Hard to answer all the Q's properly as the pistons and springs need to be measured (diameter and pressure at a test length) and these specs I can get if required. The gaskets come in the Elring kits I use and 'should' be replaced, but sealing with Master gasket 515 or similar could suffice (but not on the threads or you'll never get it out). IMO it's ok to use the grooved piston in the rear relief hole (the one near the oil pump).

it looks like the new short one is fine to use while the second one seems like it could be too long but the old ones spring is further into the piston.

Wouldnt that be real hard to work out.

The new spring maybe longer but is it still the same rating, it could be weaker so overall it could be the same pressure when installed.

So they are pressure relief valves, do they just open at a given pressure and let oil back into the sump? If you install longer ones or harder ones, does that increase the oil pressure? Is that a bad thing on VW's.

Not hijacking thread but its nice too know what it does and not just how it goes together.

From what i have read and heard the pressure relief valves work to bypass the oilcooler when cold giving the bearings more oil. then when it gets hot and pressure it stops somehow (and if it doesnt you could be in a bad way as oil wouldnt be going to the cooler. The new one is deffiently longer than the orig.. I'm thinking i should just use the orig stuff and put these into the parts pile.