Lifter Noise at Start-Up

I believe this is a typical issue with AMC 390's...upon cold start-ups the lifters make noise, maybe a second or two, until oil pressure is up, which on my car is about 45 lbs at idle and 60 under load. Can anyone recommend an oil additive that can decrease the wear that must be happening on these starts?

1968 AMX 390 Automatic
Turbo Silver / Red Command Station Interior
"The Orbiter"

Unfortunately it is a typical problem.

But the real culprit is usually the anti-drainback valve in the oil filter. The AMC filter is positioned sideways and over time on shutdown the oil will drain back into the sump. When you restart the pump must refill the filter, then it can fill the lifters. During shutdown over time those where the valves were open have leaked down. So the lifters make noise until they fill.

If the filter was already full this is essentially instant, no noise.

Of course the factory engineers new this and there is a 1-way flapper valve in the filter to prevent the leakdown.

The problem is replacement filter quality. I've never seen an orange filter where the valve actually works. I've tried a number of brands with minimal success. Tried the Napa Gold (Wix I'm told) long filter that is actually a Pontiac filter and it does not even have a valve. The current proper AMC (unfortunately short) filter has a valve, but even the NAPA gold only works about 25% of the time. I'm told a Delco filter is OK, but I have not tried so I can't verify.

The late AMC's after Chrysler bought them converted to the Chrysler filter, a simple change of the threaded adapter, and that is also the same as the Ford, which uses a long filter with a valve. Lot's of Ford filters are mounted sideways and preventing leakback is good for them. With the Ford filter so common there is much better selection of good quality brands. Never the Orange one (Thanks Dave, that's a nice way of putting it).

I now convert everything to Ford filters and have had much better luck with filter quality. Now my Rambler rarely rattles the lifters and bearings on cold start.

Okay, so can someone recommend a filter that will do the job? I'm currently using a Purolater L30005. I checked the PF24 filter, which is AC Delco, the site I found it on says it will not fit an AMC 390.

1968 AMX 390 Automatic
Turbo Silver / Red Command Station Interior
"The Orbiter"

http://www.ferrarichat.com/forum/showthread.php?t=195878&highlight=baldwin

Here is one of the posts from the Ferrari forum.

1965 Austin-Healey 3000
1970 AMX 390
1986 Ferrari 328 GTB
2005 Subaru RS25

As far as an additive the Rislone ZDDP adds 1500 ppm.

1965 Austin-Healey 3000
1970 AMX 390
1986 Ferrari 328 GTB
2005 Subaru RS25