LZ valve spring height
 

Can anyone tell me the correct installed height to reach 60-65 lbs on the valve seat when using Reds lincoln zephyr springs and stock length valves?

I read on another post 1.950 to get 80lbs. The max I would like to run is 70lbs.

Re: LZ valve spring height
 

Onliest number in the bulletins for 86H spring is test length 2.125 test length for 51-57 pounds. I'd assume the low number to be the reject number when testing used parts...
Jim Leis, now deceased, tested a bunch of combinations on here...his screen logo was something like blown 49. Need to find those posts. Jim did a LOT of good work like this, including a massive chart of compression ratios.

Re: LZ valve spring height
 

I recently went through this using Chevy length valves, but installed pressure is installed pressure. Most of mine ended up around 2.160" and 45-52#. With this valve length I used .030 shims on all of them and an extra .010 on a few. This was with new valves and new hard seats.

Re: LZ valve spring height
 

Hey 40 cpe,

Can you elaborate what you mean by installed pressure is installed pressure.?

I thought the whole idea of shims is to get the correct length of the spring which then dictates spring pressure.

Re: LZ valve spring height
 

Pressure at the specified height is a factory service spec just meant to classify a used spring as a part to keep or toss during valve work.
Installed height on a hotrod would potentially mean reaching a different pressure to meet needs for a hot cam or high RPM, and so would be accomplished experimentally by putting in shims until happiness is achieved OR the thing goes into coil bind and the project needs to be re-engineered with some other spring...

Re: LZ valve spring height
 

Sorry for the confusion, you are correct about the length dictating the pressure. All I was saying was that the length of the valve dictates the need for shims or not. Once installed to equal length, the pressure will be the same on a chevy valve or a stock length Ford valve.

Re: LZ valve spring height
 

Bruce's figures are correct..ive tested those and got 55lbs at stock installed height of 2.125. A 060 shim should get you where you want to be. The amount seats are ground can affect your spring height so checkem all

Re: LZ valve spring height
 

I can't think of any street cam that would need that much pressure, I use 50 lbs on the L-100 and 65 on the roadster track cam or the 400jr
With this kind of pressure your lifterd will take a beating and so will the cam

Re: LZ valve spring height
 

Hi Dyllon, you can alter the pressure slightly by using offset valve locks.

We use these occasionally when we need more/less pressure. They come in -.050" and +.050".

Thanks, Gary in N.Y.

P.S. How did the cam brg issue end up, just curious!.