A buddy of mine has a set of stock LT1 springs with basically no miles on them and he said he'd give them to me. If I put those on vortec heads, would I be able to run the LT1 cam with 1.6 rockers with no milling on the heads or anything? Just tryin to get that lift up as much as I can...

Thanks!

 

You will still need to check the retainer to seal clearance no matter what springs you run.

 

Don't hold me to it but I think Vortec heads need special valvesprings. I think I read it in Car Craft, but like I said not 100% sure.

 

i have heard that teh L31 head has a very small spring perch on it, which leads to teh need for machining to use larger springs. one thing you can do within hte existing spring is to shim it a little. by preloading the spring a little more you are making it a firmer spring without have to change spring diameter. it will effect teh bind height of the spring a little, but it doesn't soudn to me that the kinds of lift you are going to be seing will be any problem.

later
tim

 

I've read that the Vortec heads have very large diameter guide bosses. You have to watch what the ID of the springs are, as well as the OD. IIRC, the OD is 1.25" like every other stock valve spring. But I could be wrong on that.

I can hunt through my pile of CHP mags and get back to you. They list the correct springs that Comp Cams makes for the Vortecs.

AJ

 

The cheap a$$ K-Motions are what I used ................no prob

 

The cheap a$$ K-Motions are what I used no problem

 

A stock diameter valve spring for the L05 heads are 1.250". I think the L31 Vortec used .980" springs if I remember right.

 

I cant find any info on what diamter the springs are, which is my problem. Heres what scriggins dickey wrote:

Chuck

Where we sometimes see a problem when using 1.6 rockers is in the guide area of the head where the puchrods travel. You may have to clearance this area to avoid any contact.

Nathan Grassie

DM91RS, you just changed the springs (and only) and the 1.6 rockers run fine with the cam? Is it the LT4 cam or the LT4 hot cam?

Thanks

 

Chuck the springs are standard 1.250 diameter.

SDPC is correct...I had to clearance the pushrod holes for more clearance closer to the rocker stud.

I changed the springs, added .060 shims under the springs and used .050 Crane offset retainers to give a total of around .510-.515 total lift (retainer to seal).

I am running the stock LT4 cam with the 1.6 rollers for a total of .480 lift

Yes everything runs fine....still tuning. WOT is much better than the LO3 heads with the LT4 cam and stock 1.5 rockers.

See Ya