Thanks for your comments.
The followers were not resurfaced when the new cam was fitted so theres one issue.
Seat pressure was 110/275- soon to be dropped!
Oil used is Shell Helix 20/50 , intersting what you say about zinc- the cam shop in Auckland that I'm using for the new cam said exactly the same thing.
Cheers
Dave

NEVER use used lifters on a new cam and vice versa. it will fail. in minutes
lifters are supposed to have a slightly convex surface.(high in the middle)
most machines grind them with flat taper only the sunnen machine puts a proper radius on them

seat pressure isnt the issue as pressure only goes up as the valve opens
excessive open pressure wipes lobes
if the springs are coil binding you will wipe lobes
how much clearance do you have to coil bind? this is critical!

i would run 90 to 100 on the seat and 180 to 200 open
its only a little valve
too low pressures are just as bad as the valve train bounces. the lifter acts like a little hammer.

modern oils are designed for cars with catalytics converters.
what oil were you running?
zinc wrecks cat converters but is really good for flat tappet camshafts.
crane cams and joe gibbs do a running in additive that works.
with the right oil and additives you MAY have gotten away with 275lbs

does your "expert" actually have a valve spring tester or does he believe what they tell you in the catalogs?

Yes, far from impressed. I guess thats one I have to put down to experience.
Hopefully all under control now.

Holy Crap,

So called expert needs to give you a whopping refund mate.

Sounds like sabotage!! Hahaha.

Good luck with getting it all back together.

Okay, seat pressure exhaust 110/ 275 and inlet 100/270 so it appears to be way too high.Interesting - a so called expert set them up in that head....

It is not recommend to use old lifters, even if they had only been used for 10 hours previously. The 20-minute run in procedure matches them to the previous cam.

Sheesh that's scary stuff....completely worn.

Any pictures?

Well if the followers were not flat (and surface finished) to start with then they certainly would affect the profile of the lobes. The fact that they are now concave would indicate that they had also been contacting more surface area of the lobes (as the lobes began to wear down) so the wear process was magnified and intensified.

Pics would be helpful.

The followers were resurfaced for a new cam that would not have done 10 hours work and did not perform to expectations.
A new cam was fitted and the engine was run for around 20 minutes at 2000rpm followers were not resurfaced for the new cam.
This cam would not have done 500kms and is completely worn out. What is of note is that some of the lifters appear to have been machined much more than others, almost to the point of being concave and the worst of the worn lobes correspond with these ones.
I originally thought that I may have a worn valve spring issue but they appear to be fine, in fact I think they have too much- 110lb seat pressure.
Dave

I'm with bige on the run-in time. Or how it was run-in.

It's on an A series. It was a reground used cam and refaced lifters. (I donated the core )