New Valve springs (Green Paint)

[PAULJAC47]

Guyz, new set of valve springs for a z9 ,noticed green paint on one end of both inner and outer springs,look the same both ends no tighter coils,always thought valve springs tighter wind towards head,only thing i can find on the net is on a car forum which says painted end goes towards head and on a thumper forum it says paint is opp to tighter end of spring so paint should be uppermost?,any one else come across this? looked at two set of springs that have come out,no sign of paint marking?coils look id both ends....may be .5 mill tighter at one end but hard to tell,using drill bits as gauges.
Paul J

[needaz1100r]

Paint is normally a rating code.

ie lb/in. Doesn't explain why the same colour on inner and outer, but we don't know their codes.

I don't think there is a correct way up, as far as the spring knows it is being pressed from both ends.

[buzzard]

Not sure what paint is. Got some new APE springs here no paint so could go up any way. Don't think it matters but might be wrong. Sorry not much help, Buzzard.

[needaz1100r]

Not sure what paint is. Got some new APE springs here no paint so could go up any way. Don't think it matters but might be wrong. Sorry not much help, Buzzard.

I've been thinking about this - if the springs are single rate, i.e. the same coil rate throughout the whole length, then they can go either way up.

BUT, if they are dual or progressive rate, i.e. the coils get tighter then they should go with the tighter coils against the head.

The reason is that the end with the most coils is heavier, and the end that moves in relation to the head is the end that is in contact with the valve spring keeper, and therefore has a momentum away from the head and against the keeper, it stands to reason you would want to keep that momentum as low as possible.

I haven't however, ever seen a variable rate valve spring, not saying they don't exist, but I haven't seen one.

[PAULJAC47]

http://www.thumpertalk.com/topic/660781 ... e-springs/

This is what is confusing meself!!! hadnt seen the paint would have put em in either way as every set i have evet fitted....

[needaz1100r]

http://www.thumpertalk.com/topic/660781-installing-valve-springs/

This is what is confusing meself!!! hadnt seen the paint would have put em in either way as every set i have evet fitted....

I think that says what I said, but the conclusion is, if they are not variable rate, i.e. the pitch and wire diameter are the same at both ends they can go either way.

I don't believe the "put them in the wrong way and the motor was dead in 30 minutes", what we are talking about would only be an issue at the extremes here - that was someone who fucked up a build and was looking for an excuse.

[PAULJAC47]

Yes agree Mark, in this case cant see any variance in the springs either end,if there had not been any marking would have just installed either way ...

[buzzard]

measured wire diameter on springs with vernier same all the way through, i dont think it matters what way they go. ive never worried what way round they go, never had any problems. buzzard.