Valve Spring Installation

[wamnram]

I was reading in Vern Tardel's book that when installing the valve springs, the tighter wound coils go to the top (valve guide) and the looser wound coils go toward the valve stem end. Does anyone know why or what happens if they're not??

 

[flatheadmurre]

Unevenly wound means you got a progressive spring.
Should work any way you turn it.
I have an idee about why you want the most coils at the static end....but its a non issue

 

[wamnram]

I was thinking possibly because the tighter wound coils collapse first around the valve guide they may help keep the valve aligned and prevent premature wear between valve stem and valve guide?? (This would be assuming the contact between the lifter and valve stem was not perfectly flat, thereby causing the valve to want to slide off to the side of the lifter).

 

[Ronnie]

http://www.hotrod.com/how-to/engine/hrdp-1011-what-you-need-to-know-about-valvesprings/

R

 

[GOSFAST]

Just to add some, in a progressively wound spring, the closer wound coils make contact with each other using a relatively minimum amount of movement and become ineffective. This scenario raises the spring constant.

The spring constant increases for a progressively wound spring when these coils make contact with each other and there's no add'l movement in that area of the spring. If they aren't contributing to the spring load, it doesn't make sense to have more coils than necessary moving up and down. That just adds weight to the valve assembly on the top side.

For this "design" reason they wouldn't go towards the head of the valve.

To sum it up, this setup minimizes the weight that is moving (the sprung weight). This is very reason for installing the "closer" coils at the point of the least movement, it's almost a common-sense call! It would be similar/equivalent to installing "lighweight" valves, this is always a plus!

Realistically it would fall under the heading of "Valve Train Stability".

Thanks, Gary in N.Y.

P.S. The highlighted section above is the best reason for installing them the way they were designed to operate.

 

[wamnram]

Thanks Ronnie! Good read with good info. I guess my original question though is still not answered ( not that it needs to be, just that inquiring minds want to know).

 

[wamnram]

Thanks Gary, I like it!

 

[JWL]

The technical reason is to minimize weight the lobe and lifter see. However, in 99 percent of the cases the direction would be of no significance.