Comp cams Valve spring help

I have a set of Comp Cams 928 valve springs that I am planning to install on a set of early scj aluminum heads. I went to comp's web site to find the recommended installed height and I think I am seeing conflicting information, but would like someone more knowledgeable than I to look at it and clue me in.
First in their valve spring chart, it says the 928 installed height is 1.850
http://www.compcams.com/Base/pdf/ValveSpringChart.pdf

In the product info for the spring they list the seat load at 1.880

So do I shim to set the installed height at 1.850 or 1.880?
http://www.compperformancegroupstores.com/store/merchant.mvc?Store_Code=CC&Screen=PROD&Product_Code=928-16&Category_Code=

HorsinAround wrote:I have a set of Comp Cams 928 valve springs that I am planning to install on a set of early scj aluminum heads. I went to comp's web site to find the recommended installed height and I think I am seeing conflicting information, but would like someone more knowledgeable than I to look at it and clue me in.
First in their valve spring chart, it says the 928 installed height is 1.850
http://www.compcams.com/Base/pdf/ValveSpringChart.pdf

In the product info for the spring they list the seat load at 1.880

So do I shim to set the installed height at 1.850 or 1.880?
http://www.compperformancegroupstores.com/store/merchant.mvc?Store_Code=CC&Screen=PROD&Product_Code=928-16&Category_Code=

They can be installed at ANY height which will give the correct recommended amounts of force and allow the correct amount of valve lift.

read the cam card and set to required spring spec

Ok, I am looking at the cam card and the only thing it says about the springs is "recommended CC valve spring 928. Valve spring specs furnished with springs."

Since I got the cam, lifters and springs from a friend of mine and he didn't have any paperwork with the springs, so I am trying to go off the website.
Also, the alum. Cobra jet heads came off a 530 pulling motor that had a .8 lift roller cam, so I believe the valves are longer than stock. (with the 928 springs, I am having to shim .090 on the intakes and .150 on the exhaust) The cam I am going to use is comp. p/n 34-653-5 and the specs are as follows
Grind FF 310B-8

Valve adjustment .030 intake and exhaust
Gross valve lift Intake .656, exhaust .641
Duration @.020 Intake 310 exhaust 314
Timing @.020 47BTDC and 49ATDC
Installed at a 108 c/l

Duration at .050 Intake 270 exhaust 276
Lobe lift intake .3750 exhaust .371
Lobe seperation 108

Since it appears the valves are longer, I was looking at comp's valve spring chart and they list a 930 spring that has the same spring loads/rates throughout the lift range and is also set up for an installed height of 1.900 which means I won't have to use no where near the shims I have used on the first 3 chambers. Any thoughts?

Use whatever spring at whatever installed height you want which will give you the correct amounts of force and allow the required valve lift; (hopefully .090" before coil bind in a race type situation).

Been messing with this over the weekend and after talking with Comp Cams yesterday, ordered a set of CC double springs that will give me the recommended seat pressure and open pressure with a 1.900 installed height for the intakes. However I was still not satisfied with the situation on the exhaust side and after measuring it appears that the pockets have been cut deeper which explains why I'm seeing a 2.00 installed height with stock length valves. So last night I happened to glance over at a set of Manley Nextec doubles I had on the shelf that are +.100 and took the inside spring out then measured the force of the outer spring and damper and at a 2.00 installed height, the open and seat pressures are perfect. So is there any reason why I couldn't use outer's of the Manley set I have?