Recommended Valve Spring Height

[AMXguy]

My new Crane 64308-1  valve spring and retainer kit says recommended installed height of 1.875, I'm at 1.835-1.870 ,  is the added pressure of these short ones going to be enough to worry about over the nose?

 They say this height will give 90 lbs closed and 280 lbs over the nose which without knowing your lift I don't know how they can say that. I'm just going to run a cam around what a stock 440 six pack had so nothing radical.  is this anything to worry about.

[femtnmax]

If you could check the spring pressure at the shorter installed height it would be nice.  But I have seen valve spring checkers that were way off calibration.  I ended up buying a calibration spring just for that purpose.
The relatively low spring pressure probably wont be that much higher at the reduced height, and the springs will loose some pressure rating with time, so you could be A-OK.

IF you could measure each spring, then you could match weak springs with shorter installed height to help load them a little more.   Then the installed seat pressure could be close to the same for all the valves.   JMO

[moper]

I would be much more concerned with why the installed heights are that far apart, rather than the spring rate. They should all be at the same height, whether it be short, or tall... Not mixed over .040"..

[71chally416]

Bad valve job alert! 

[femtnmax]

Both the last two posts are correct.  I was just trying to salvage what was there.   A correct valve job would have had all the seats cut to the same level, so all the valve stem lengths end up at the same height.  This is real important, especially for correct lifter preload on non- adjustable shaft type rocker arms.

[AMXguy]

I'm going to send them off to a shop I know I can trust before I put them together, I will be using Crane adjustable rockers so I can take care of heigth but the metal where the bronze guide comes out of the head is chiping off.  I'm just measuring with calipers too, not the proper equipment so that could account for some of my variation.

 Even though this shop has a good reputation I'm never buying anything not done by my own shop and done for me. a good deal seems like always cost me more in the end.

[71chally416]

I hope they don't intend to sink all the valves the same to equalize the stem height. Every one you sink costs you HP. The entire margin of all the valves heads should all be above the chamber floors. Cut the stems, NOT the seats. 

I've seen so many Mopar heads ruined by bad valve jobs in the last 20 years I'm convinced at least half of them in circulation are junk. They'll work and the motor will run, but never as good as when they came from the factory.

[moper]

It's fairly common for the bits of existing iron guide (part of the casting) to splay out and crack when the bronze gets pressed in. I've always knocked whatever was loose, but you may be surprised at how bad it looks, but hoe attached that piece is...lol.