Proper valve springs for E7's with an X-cam?

The problem is the ebay info isn't verified, it's the sellers ad. If you want proper tech advice about those particular springs, contact Comp Cams about them rather than ebay. Odd thing is from what I see, they should work with the X cam. And yes, performance valve springs will be taller than the wimpy stock springs. They'll be 1.750 inch tall when installed, and you won't get coil bind until 1.150 inch.

Well, from what I've been told is I need the heads machined a bit for them to work. I'm not sure what exactly would be involved in that.

I've tried compressing one spring on there, and by the time I can get the locks in, its almost already experiencing coil bind. They'll work fine with the cam, I just can't seem to get them to work with these heads.. They just seem way too tall. The inside springs also barely slide over the valve seal..

If you are going to start messing with valve springs you have to have a pressure measuring tool and some way to measure height.

Otherwise you can get in trouble fast.

I have a scale that measures pressure that goes under the spring, and I can push down on the spring with my milling machine turrert to measure coil bind and pressure. I have dial calipers and a tension gauge that fits the rockers.

If you have brand new springs, all you really need is a dial caliper and a rocker arm style of spring pressure gauge.

You could even get away without the pressure gauge if you know the installed height and are willing to accept some pressure errors from tolerances.

The entire problem you have might easily be cured with different retainers and/or keepers. So long as the rocker doesn't contact the retainer you can use a retainer that moves the installed height up.

As I recall stock heads were either 1.7" or around 1.82" installed height. I'm reasonably sure the HO motors were 1.7". That means if you have a spring the correct diameter and the correct retainer and the seat matches the spring, you could easily use those springs for a cam up to .500 or .525 lift. Coil bind would be at .600 lift if you set at 1.750 installed height.

My personal opinion is I would never use those springs for anything close to or above .500 lift. I always like to have springs at least .2 inches out of coil bind, and actually as much as possible out of coil bind. Spring life will go way way up if you stay at least .25 inches out of bind.

What that requires is a taller spring. This is why when I do a valve train I find the maxium possible installed height the rockers allow. Then I look at springs based on that. I either have the seats machined deeper or use retainers or keepers that move the installed height up.

The difference in spring life is dramatic if the spring is at least .2 inches out of coil bind, although you can get away with .1 inch.

Tom

cindys_sn95 said:

those comp springs will be fine for the x cam. but to make them work on stock heads they will have to be machined for the springs. spring seats will have to be cut and probably guides also. my question is why bother with e7s? after all that machine work and money they are still e7s! :nono:

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I got them for free, so I'm more or less attempting to port them and run them for the rest of the summer. The motor thats in my car is getting weak (cyl#1 is losing compression), and I'm just trying to build a fairly stout motor to put in soon. I will definitely upgrade over the winter, until then I'm just using what I can.

And I'm trying to avoid spending any money on machinework, since I'm not planning to use these heads for all that terribly long. Thats why I'm looking for a set of decent springs that'll work without any machinework.