It sure doesn't sound common.  Lifter bores sometimes move due to core shift.  I'm wondering if that may play a part?

TKOPerformance wrote:

It sure doesn't sound common.  Lifter bores sometimes move due to core shift.  I'm wondering if that may play a part?

I'm thinking that the dimension from the cam lobe to the rocker is the same regardless of any lifter boss shift.  I made some solid roller lifters by making aluminum plugs to replace the guts and including hardened steel pushrod seats...has some left over from way back in the four-banger days.
The lifters are within .001 of being the same length.  I check the adjustable pushrods after each cyl. 
It takes a lot of pushrod change to move the roller contact point on the valve stem just a little bit so I'm thinking the problem...if it is and I don't think it will actually matter...is in the heads.  Either valve angles or rocker stud angles which would make big differences with small variations.
I'll know more tomorrow or over the weekend and will let you know.

BB1

TKOPerformance wrote:

I would verify that the rockers studs are true, and if not correct that first.  Then consider valve angles.

Have you contacted AFR about the machining issues with the heads?  I'm really taken aback by that.  My AFRs were pieces of artwork.

I've been noodleing this all night and I'm sure it's the rocker studs.  The valve stems height was all over the place but the angles are very good, and we fixed the stem height on this rebuild.  This morning I'm going to install all the studs without the guide plates.  I believe the stamped guide plates are the biggest problem as they tend to put uneven torquing loads on the studs.  It takes very little stud tilt to move the roller contact point...obviously.  But it takes a lot of pushrod length change to correct it.  If I had my mill set up I would surface them.
Got a plan...will let you know.

Well I was right...I think.  I removed all the guide plates and torqued the studs down directly to the heads.  No angularity issues, the studs were all within .010 at the top according to my straight edge and feeler gauge.  So I put the plates back in and discovered that by moving the plates around a bit to change the contact area under the studs I could get a fairly centered contact point with the rocker.  Have two that are just slightly off center but not enough to get excited about.  This is all with the 6.400" rods so I can use what I have.  What a PIA...I could easily be talked into bolting on the old ported E7TE heads that I had on it way back.  Won't, but don't tempt me.  Indexed the cam...it's within a couple of degrees of the timing card so I'm happy.

Now...if anyone has an extra AOD-E (Not 4R70W) pan they can spare I'm pretty close to putting all this crap into one pile.

Thanks for the thinking guys.

 

Did you advance the cam or...install it straight up  or....was there advance already 'ground-in' the cam?
My cam from Delta was neutral....No advance ground in.
Glad you got it 'fingered-out'!!!
6sal6

BobE wrote:

BB - so, what do you attribute the problem was? 
That the guide plates weren't always being torqued flush on the pedestal mount?

Due to some basic bone-headedness I got heads with screw-in stud mounted rockers, not pedestals.  The studs have flanges that provide a torque surface to pull down to the mating surface on the head.  The guide plates are mounted under the studs.  The guide plates are stamped and hardened and have a rather large hole through which the head end of the stud can pass.  The problem seems to be that the hole is large enough to allow the stud flange to NOT torque down evenly which causes a slight tipping of the stud due to minor thread slop between the head and stud.  It does not take much unevenness at the flange to cause the top of the stud to lean off center enough to put the rocker tip way off the center of the valve stem.  By carefully positioning the guide plate it's possible to mitigate most of this issue.   Crappy system IMO.  

I think I used the 7/16 'Shivel-lay' studs in mine too......(when I had one break on the way to Texas many-many years ago.me & BILLY WALTON wus-a traveling together broke just as I got to 'Aller-bammer')
ARP ones!\6s6

On my son's 351W I used Trick Flow Twisted Wedge heads.  The Valves are angled.  But I pulled a roller lifter apart and threw some washers in it so it was solid lifter.  I don't recall what final measurement was but they all came out really close do one another.  So I only needed one sized pushrod.

Steve69

On my AFRs I hada chit can the one piece guide plates and use somebody's, maybe Comp Cams, 2 piece interlocking adjustable guide plates.

I usually take it as a given that the lifters won't come out with the heads installed.  Probably because I'm always using aftermarket lifters that are taller than stock. 

On the gaskets, what kind are you using?  Reason I ask is that you can clean MLS gaskets and reuse them.  I've even heard of guys separating the layers and cleaning each layer individually.  I'll add that they are very good gaskets in all other respects too.

Permatex 80652 remove silicone and the residue without damaging the gaskets.  I will always ere on the side of caution, but MLS gaskets are pricey, so if they can be saved and reused I'm always game for that.  Just a thought. 

Bullet Bob wrote:

BobE wrote:

BB - so, what do you attribute the problem was? 
That the guide plates weren't always being torqued flush on the pedestal mount?

Due to some basic bone-headedness I got heads with screw-in stud mounted rockers, not pedestals.  The studs have flanges that provide a torque surface to pull down to the mating surface on the head.  The guide plates are mounted under the studs.  The guide plates are stamped and hardened and have a rather large hole through which the head end of the stud can pass.  The problem seems to be that the hole is large enough to allow the stud flange to NOT torque down evenly which causes a slight tipping of the stud due to minor thread slop between the head and stud.  It does not take much unevenness at the flange to cause the top of the stud to lean off center enough to put the rocker tip way off the center of the valve stem.  By carefully positioning the guide plate it's possible to mitigate most of this issue.   Crappy system IMO.  

BB - thanks for the update.