I had my vortec heads ALL set up & installed (CC 26918 springs,787 retainers & +.050 locks- NO machining required). When I put my roller rockers on I noticed several rails contacting the retainers and the rest had very little clearance. Darn the luck! I don't want to compromise the integrity of the valve guide by machining them down, being that the guide also serves as the spring locator, and I know I can't machine the spring pocket down to get my needed 1.8" installed height. I was thinking .100" longer valves, but don't really want the added expense. Lash caps are not an option, as they aren't compatable with (self align) rail rockers. It was suggested I trim the rocker rails a bit to get the clearance I need. Any input/suggestions welcomed. Thanks.

 

Sounds like you may need longer pushrods. Did you check the valve train geometry?

If the geometry is correct, the other option is a better brand/style of rocker that allows more clearance under the rocker. Aluminum roller rockers are bad for that. I have seen the underside of the rockers ground down for a little more clearance but I wouldn't do it.

Even if you go with longer valves to get your install height, you'll still need longer pushrods to fix the geometry.

 

Why the .050" offset locks? I setup my Vortecs with the 26918 springs (and associated hardware) ,a zero lock with no interference.

 

My exhaust valves use +0.050" keepers to give me a little more valve spring install height so I don't get coil bind. Without them, I can't make the minimum height. With them, I use shims under the springs to make up the difference.

My intake valves are +0.250" so that I can get my minimum valve spring install height. The longer valve needs some modifications to the valve train to get good geometry. My rocker stands needed to be taller and pushrods needed to be longer.

 

I understand the concept. I have a .100" longer valve in my RHS heads, use an .050" lock combined with shims to achieve my installed height just as you have. Although in my case it wasn't coil bind that was the issue. It was that without the offset, I was less than my target height and I needed the extra height from the lock to gain enough room and then put in a shim.
My question is why the OP is using an offset lock in a Vortec head in the first place. It wasn't needed in my original OEM Vortec build as the valves are standard length and I found plenty of room between the retainer and the top of the guide (seal actually). The relatively small retainer used with the 26918 spring provides this additional room (along with the benefits of reduced valve train weight).

 

SkinnyZ, exactly as Alky said. The +.050 locks allowed me to get darn close to the recommended 1.8" spring installed height(1.79") thus keeping seat and open spring pressures where they belong. It gave me .050" extra retainer to seal clearance at the same time(+/-.590"). I measured a few valves from lock groove to tip and sure enough, there is some variance. I was informed that vortec valves are .290" from groove to tip whereas standard sbc valves are .250". The valve with actual rocker to retainer contact is .25". The valve with SOME rocker rail to retainer clearance is .29". I don't know if the previous owner swapped some valves or ground the tips. Oh well, it's MY problem now. I'm wondering could I shave OFF the rails and use guide plates? I REALLY don't want to spend $$ on new valves. I haven't set up the geometry yet as it seems kinda moot right now. I'm anticipating that I MAY need different pushrods.

 

The rockers are Comp Pro Magnum rollers (chromemoly)self aligning. Geometry VISUALLY looked pretty good. Just looked at the roller sweep in the residual oil on valve stem after pulling rocker. I'll use a sharpie after I reinstall them. BTW, my cam specs are 222/230 dur. @ .050; .509I/.528E with 1.5 rockers. The Comp pro magnums are 1.52 ratio.

 

I did use a Comp Pro Magnum rocker however that was without guide rails as I went the guide plate route. 1.6 ratio and Comp Magnum 7609 pushrods as well.
If I recall correctly a stock Vortec spring also has an installed height of 1.7" which may explain the unique keeper groove location (something I didn't know) and why my current after market Vortecs have .100" longer valves.
That would be in keeping with a more traditional 1.8" installed aftermarket spring.
I suppose the difference is in the self aligning vs non self aligning aspect of the rocker.
Any pictures of your assembly?

 

Might be able to post a pic in a couple days (no digital camera). I have a set of BAD vortec heads I may be able to pull valves from and use. I'll find out if they'll work on my next day off. Thanks guys.

 

Subscribed.....Having the same issue with prw 1.52 roller tip

 

Heres an informative read for you

http://www.pacificp.com/forum/viewto...905825b919fbf8

 

Thanks! It was interesting.
On my PRW 1.52 roller tip rockers I had some of them that have .040" clearance between the side rails and the retainer top and some were almost hitting ( less than .005)
In the article above I noted the depth of the side rail to the roller as .065". I measured mine and on the rollers rails that were close to touching I shaved them down with a grinder and sanding disc. All are now clear of the rockers by .030" to .040" with a minumum of .065" clearance between the roller tip and the side rail.
As far as I can tell, the difference is when the bushing for the roller tip is drilled, It varies and thus the depth of the side rails vary. Along as I keep the .065 as in the link above I should be OK.

So your post to the link really helped.
Thanks!