Valve spring question

[ralmo94]

Hey all, as the title says I have a valve spring question. Having never built a motor myself, I've worked on quite a few, mostly my own, or friends stuff..

I have a 98 l29 454. I have a GM performance parts camshaft for it.
I had purchased a set of springs for the cam change, they might be a little light, but it didn't bother me since I don't plan on winding it up much, according to camquest, peak torque should be around 2k, and drop after 3k, don't wind it up much past 3k stock.

I have a set of heads from a 90's 427 HD most likely, from the research I've done, they appear to be the same minus the vortec stuff that makes them vortec.

Further research has shown me that a set of comp cams 911 springs would better fit my cam.

Now for the question, sorry for so long to get to it, but I don't know about outside valve spring diameter. I put a caliper on the valve springs on my heads I plan on using, and it seams they are inch and a half. The springs I have are 1.44", comp 911 springs say they are 1.56".

Would the 0.06 over inch and a half be a problem, or even measurable with a cheap caliper? Would the 1.44 in springs I already have be too small?

I plan on keeping the net lash and the rotators, they are on all 16 valves.

Any guidance or input is welcome.
Thanks for reading if you made it this far.

 

[Schurkey]

"Net lash" is probably acceptable given the GM replacement cam--likely has a similar base-circle. Not my first choice, but probably acceptable.

Keeping the rotators is really questionable. The ones from my L29 Vortec heads had a taper on the valve spring side, which didn't give me a good feeling when pushed-on by stiffer springs.

When I went with a bigger cam on my Vortec heads, I pitched the net-lash rocker bolts and the rotators in the scrap bin. Way back then, there were two designs of rotator eliminator shims--one part number for the "usual" ones, and one part number for the Beehive-spring shims. I needed two sets of eight because all sixteen valve springs had rotators. Some of the intake (not exhaust) valve guides had to be trimmed because the fillet at the bottom interfered with the shim sitting flat on the valve spring seat.

 

[ralmo94]

Keeping the rotators is really questionable

With a 4k redline it doesn't bother me, also lighter spring pressure. Going for torque here. I have read of guys just slapping the new bump stick in with factory valve train.

The real question is the diameter, all the research I find talks about the spring pocket in the head, the rotors are in there though, again talking 1.44 or 1.56, does it matter between the 2?

Thanks for your thoughts on all this.

 

[evilunclegrimace]

With a 4k redline it doesn't bother me, also lighter spring pressure. Going for torque here. I have read of guys just slapping the new bump stick in with factory valve train.

The real question is the diameter, all the research I find talks about the spring pocket in the head, the rotors are in there though, again talking 1.44 or 1.56, does it matter between the 2?

Thanks for your thoughts on all this.

What size is the spring pocket in the head? That is going to determine what diameter spring that you can run without machining the pockets.

 

[Schurkey]

And you could measure the spring pocket accurately enough with a caliper.

 

[ralmo94]

What size is the spring pocket in the head? That is going to determine what diameter spring that you can run without machining the pockets.

I'm not setting the springs in the pockets though, they will be on top of the rotators. What I'm gathering from this so far, and thinking about it, the 1.44 springs I have should work ok?