ok, so I started the task of replacing the valve stem seals this morning.
I purchased new springs, seals, ect. from Summit, (the kit) and there are two things that have me stumped. 1. the retainers on top of the exhaust valve springs, are different from the ones on the intake springs. In the new kit, there were only retainers for the intake and none that looked like the exhaust. I'm thinking that I cannot use the intake style retainers on the exhaust. Is this correct? And if so, what are my options?

2. All the new springs are approximately 1/4" taller than the old ones.
Is this going to be a problem? Or should I stick with the old springs?

I'm really trying to invoke the "While you're in there" rule and replace all the parts and not just the seals.

The engine is a 73 350, (original) and never been apart.

Thanks in advance for any kind words of advice.

Steve

 

I'm not sure I can answer your entire question. On the exhaust valves you have retainers that rotate the valve. In the new kit are there 16 retainers or just 8 ?

 

I had my 350 out of the car last winter and installed a new cam while it was out. In doing so I also installed new springs.


The dome shaped caps in your photo are a GM item used to assist keeping oil from getting down the valve stem and finding its way thru the guide.

I re used my and at teh same time I installed new oil seal O rings.


As for the retainer. Not sure why one of yous is so much thicker than the other. In the end its job is to hold the top of the spring after the keeper is installed. All 16 of mine were the same retainer. Both the old and the new ones that came with the springs.


The critical thing to check is the installed height of teh spring.


That is when the spring is installed with the keeper and retainer what is the height from the bottom to the top of the spring. This is measured with no rocker arm pressure.


You then may have to shim .015 / .030 /.060 or a combination to get the desired height +or - .005. You can also buy keepers taht offer a plus or minus value from standard.


As I recall the dome shaped cap gives .030 just by its self.


Then when the rockers are installed you have to compress spring fully by rotating motor and measuring the remaining space before the coils bind up. Should have at least .060 remaining travel before binding.


Hope this helps

 

Not sure just what the correct names are for these parts, but just so we're all talking apples and apples here.......

There is a "cup" that fits upside down over the top of each spring, on top of each "cup" there is metal "cap" to retain the split locks. In the kit, there were 16 "caps" simular to the ones on all the intake valves. My first guess was that the thick caps on the exhaust valves were to rotate the valve as stated by DWncchs.
I suppose if push come to shove, I can re-use the exhaust caps.

 

Be careful when changing the springs to a stronger spring. The studs are only pressed in and can pull out if the spring is to stiff. I had this happen to my original heads before I changed to the Edelbrock RPM heads.

 

Thats just it, I don't know if the springs are too stiff
or not. I'm thinking that the height of the spring isn't
a big deal, because I'm only going to adjust them, just
enough to take the play out of the pushrod. I'm hoping
that someone with a little more knowledge on this will
either agree with, or correct me.

 

Or wipe out some lobes on the cam.

 

make sure your installed height and spring pressure is close to stock or you will pull studs flatten cam and worse coil bind. 105#@1.700 valve closed ,,296lbs@1.200 open. any more and you can have problems .....

 

All very interesting responses indeed. I don't suppose that anyone on here has
pictures showing just how the height of the springs are measured? And is there
some sort of tool for measuring the pounds of force needed to open the valve?

 

Summit has a direct reading seat pressure tester to measure and shim the spring to the appropriate pressure.