Upgrading from single springs w/dampers to dual springs

[62Ranchero200]

Greetings Ford Six Fans,

For the last five years, I have been running single springs w/dampers with my 274H cam.

I have some dual springs (CSC-TOY-SPG) that I would like installed on my aluminum head for my 280H cam.

My valve guides have already been machined down about .050 to accommodate the higher lift of the 280H cam.

Is there anything else that needs to be done to the head to install the dual springs? My machinist took a look and believes that (after machine the valve guides) the dual springs should install without issues.

Thanks
Bob

 

[62Ranchero200]

I'm a bit surprised if no one has done this. Did everyone either order their aluminum head already with dual springs, or order it with single springs and never upgrade?

The Clay Smith Cams web site mentions that the valve seats and valve guides should be machined to install these springs. I can see why the valve guides would have to be machined - if you approach .525 lift as the heads came from CI/come from VI, retainer to seal clearance is tight.

But, I don't understand why machining the valve seats would be necessary, unless that applies only when these springs are installed on factory cast iron heads. Please advise if, and why machining the valve seats would be necessary when installing these springs on a CI/VI aluminum head.

Thanks,
Bob

 

[bubba22349]

HI Bob, yes that Clay Smith info dose sound wrong about machining the valve seats for a duel spring install maybe it's a typo. However somtimes on the top of the heads at the valve spring seat pocket (where the spring registers) and or the valve guides outer diameter will need to be machined so the duel springs wil fit correctly i.e. both will sit flat.

One thing you do need to be carful of on the C.I. / V. I. Aluminum 2V heads is there isn't much material in that spring seat area above the intake ports so you don't want to be lowering the spring seats at all just widen the spring pocket if needed to fit the outer diameter of the spring then if the guide is two big for the inner spring it may need to be cut on its outside diameter. Good luck sounds like your getting close now.

 

[pmuller9]

See post #74 and #75
viewtopic.php?p=629052#p629052

 

[bubba22349]

Yeah it looks like you covered it well pmuller9, that picture detail is a nice touch too.

 

[wsa111]

I know Comp. Cams makes several keepers that can change the spring height.
I believe one compresses, another one is centered & the third makes the installed height higher. +.050"
As mentioned before do not deepen the intake spring seat otherwise you will in the intake port.
Also since this is an aluminium head you need hardened spring seats to prevent the valve spring from chewing the head.