Does anyone know what the height should be for stock springs and valves on a 69 455 Toronado?

 

1.67"

 

That’s what I thought. Actually I thought it was 1.7”. Had my C heads done, was thinking that the height would be more after machining and I would have to shim the springs. Now I’m only getting 1.5”. Apparently he didn’t put in the same length valves? Now I’ve got a new cam in there, required springs are 1.7”

 

Double check your measurements. I assume you are not using valve rotators. Something is not right.

 

Yes, valve rotators on all.

 

but I thought you measured from the spring seat to the bottom of the retainer so should it matter?

 

Valve rotators not used on any "C" heads. The later heads with rotators had deeper spring pockets to accommodate the rotators.

 

Where new seats installed?

 

^^^^^^^^---This is correct !!!!!! Kevdog, the valve rotators are your problem.

 

Hmmm well I don’t know when they were put on. can’t imagine the machine shop put them on

 

So the valve rotators sit lower on the valve stem than a regular retainer?

 

Correct !!!!! Thats why heads using valve rotators had the spring pockets machined deeper.

 

The heads with deep pockets and rotators had the same 1.67" installed height when new and valve/head sealing areas were not cut by a valve job. If you deleted the rotators and used regular retainers on deep pockets, you would have 1.88" installed height. Olds offered thick spacers to take up that difference (about .2" thick) but they were soft steel. The spring dampers chew into soft spacers or shims. so I get hardened stuff from Comp Cams, etc. if I need to use shims. If the springs don't end up nesting into cups machined in the heads, you should use spring locating shims that hold the inside or outside of the spring so it doesn't dance around.

 

 

it’s possible but I’m not 100% sure

 

Ok thanks, I have a 69 400 back in the corner. I’ll go look see if I can get some retainers off of it and check my measurements again.

 

Welp, 1.67” with stock retainers. Lol thanks guys. I’m still learning new things about these old cars.

 

Great !!!! You did the right thing to measure before running it and found the problem.