1. I have read the lifter valley line may/may not be important. For those who say it isn’t, why not?

2. External oil filter pickup line/road race setups(think milodon) since I expect pushing Gs in several directions, would this be of great importance compared to other mods or only extra insurance?

3. I read somewhere that an issue might be keeping oil in the pan(sounded like drainback issues) if anyone knows about that, please enlighten me.

4. Any other oiling info or suggestions? I would like to have this thing ready and right the first time. 

Thanks in advance.

To reduce/eliminate the aeration of the oil at high rpms I modify a Mopar 340 windage tray for use in the AMC V-8. Also use the Canton drag/road race eight quart pan.

-Steve-

I don't think you will ever get a consensus answer on the valley oil line mod, my view is that there is only so much oil to go around in a pressurized system with controlled leakage (i.e. bearing clearances), so adding an extra pipe to the same location isn't going to deliver any more oil and possibly introduce addition points where you can have a failure. You will of course get other opinions on the subject.

I did have a Ford 460 that broke a rocker and pitched a lifter. It probably drove 20 miles at highway speed with no oil pressure (would have had flow) and did not blow up. Sort of amazed at that one.

In an AMC V8, from failures experienced, the rear.

As pressure drops flow increases in a hydraulic system. The line therefor would not increase either pressure or flow unless a new leak path is introduced as Ken pointed out.

It must either provide an alternate path for aerated oil to break into smaller air pockets or displace air pockets at the rear of the gallery. Air would then travel up into the lifters and cause little if any short term problems.

Agree, it is not needed for an average street engine.

There are other proven oil aeration solutions at the bottom of the engine that performance people are using.

  

I just bought a Comp Cams (part# 3118) double roller timing chain for my 401 build... do I need to modify something for it to work properly?

https://www.ebay.com/itm/COMP-Cams-Timing-Chain-Gear-Set-Hi-Tech-Double-Roller-Steel-Sprockets-AMC-V8-Set/332795972368?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649" rel="nofollow - https://www.ebay.com/itm/COMP-Cams-Timing-Chain-Gear-Set-Hi-Tech-Double-Roller-Steel-Sprockets-AMC-V8-Set/332795972368?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

The oiling passage in all the aftermarket cams and timing gears needs to be checked. The front cam journal supplies a path for oil going to the distributor drive gear. Many times the timing gear has that groove in the wrong place or the groove extends beyond the diameter of the cam's front journal.

This is a comparison of an aftermarket cam gear (left) and an original AMC gear (right). You can see the aftermarket gear groove extends well beyond the distance of the original gear.

The arrow shows the timing gear groove extending past the cam journal diameter causing a loss in flow going forward to the distributor drive gear.

I've welded and machined the timing gear to fix that.

I have always done the oiling mods originally recommended by Performance American Style and never had a bearing fail. But it appears that those who don't do the mods haven't had a fail either.

Great info in this thread!

Modern thinking and track proven is oil aeration being the big problem, oil frothing in the crankcase and picking up air. The extra quart would actually aerate the oil more as the crankshaft spins through the excess oil.

This air/oil mix would then be pumped through the engine and not lubricate near as well as straight oil. Air separation in the top of the engine can cause even more problems if not achieved in the valley or rockers.

An extra quart oil pan reduces aeration of the oil and also provides for "spirited" driving as oil is pushed front to back or side to side.

The stock pan with stock oil level is good for every day driving. 

http://theamcforum.com/forum/oil-path-amc-distributor-gear-oiling_topic95506_page1.html?KW=oiling" rel="nofollow - http://theamcforum.com/forum/oil-path-amc-distributor-gear-oiling_topic95506_page1.html?KW=oiling

I am old enough to remember AMC being involved in the Trans Am racing series, and have read numerous articles over the years describing blown-up engines due to oiling problems. Of course, these cars were revving high and experiencing really high g-forces in hard cornering.  The final ultimate fix was to change over to a dry sump, belt driven external pump with a large external oil tank, very similar to what NASCAR uses today. That would be overkill for most of us. 

 

Oil return is marginal in an AMC because of small return openings in the heads

and the collection of oil in hard acceleration in the lifter gallery area.

 

Stock umbrella seals broke up and the debris blocked the returns and cause

general mayhem in the oil system.

 

Yes, I have seen a number of AMC V8s that had oil pressure

only until the oil was all pumped to the valve covers.

 

Sludge and umbrella seal debris slowed the return.

Wait a few minutes and re-start and oil pressure was back.

For a few seconds.....

 

The plastic button on the oil pick-up had a similar effect.

The button becomes dislodged and the pick up goes flat

against the bottom of the pan.

 

AMC V8 is a great motor when all is well, any motor fails with no lubricant.

I don't have the supporting documentation any more, and can't remember where I even got it, but the AMC Gen2/3 V-8 was designed for six quarts from the start. Six quarts are specified for police and heavy duty fleet use (taxis and such) -- and they use the SAME OIL PAN STAMPING. The police pan has a rudimentary baffle to keep oil from being sloshed to the front in hard stops, that's the only difference (don't know if the HD/Fleet pan is the same as police or just a standard pan). Marketing cried that a six quart oil change would make AMC engines more costly to maintain than the competition, so it was tested and found that five quarts was sufficient for normal driving, so the owners manuals state five quarts -- same as everybody else in that era.

The valley line was introduced by drag racers to help with oil starvation under hard acceleration to the rear main and rod bearings. Basically it just supplies extra volume by having another path. I think it is an aerated oil issue -- the oil gets sloshed hard enough to the rear of the pan and a lot of oil is quickly sucked up out of the pan, allowing a little air to be sucked in at the pickup. The twin paths increase the amount of oil, and should reduce aeration. I don't think it's necessary except on those really quick drag cars -- not your usual weekend bracket racer. You have to be pushing the engine near it's limits to make extreme mods like that, and I mean really built up to near max possible output. Building a 10 second or less 1/4 mile car? You might need it.

I remove the standard pan baffle, hammer and dolly the back of the pan to an outy and not an inny and re-install the standard baffle.

Next pan to do:

http://theamcforum.com/forum/amc-v8-police-oil-pan-variant_topic97910_page1.html" rel="nofollow - http://theamcforum.com/forum/amc-v8-police-oil-pan-variant_topic97910_page1.html

 

Quotes from that thread posted by Steve P, an actual Engineer who worked at AMC:

 

Steve_P wrote: There is nothing about the design plan was for 6 quarts of oil in the AMC SAE papers- that's an urban legend that I think goes back to the CACI newsletter days. The bearing clearances are wrong in the quote by LM. .0015 is way too tight for the rear main. The bearing clearances were also loosened up by AMC from the 68-70 "tight" spec, which was ~.001-.002 to a more clearance sometime around 72- which coincidentally is when AMC was selling a substantial amount police cars. The new clearance specs are what most use now, ~.002" and ~.003 on the rear main. I have ran a pan dry at 4500-5000 RPM sustained driving and spun a #8 rod bearing. And I know others that also have. If you haven't, consider yourself lucky. With an 8+ quart pan, no more issues.

 

Steve_P wrote: There is a mention in the SAE papers for the 390 that they made a modification to the oil pan sump cover plate when the 390 was introduced- IIRC they added the drain slots on the side at that point.    Yes, there is no issue with the AMC oil pump gear size- more than big enough, compare to a SBC. Years back someone was selling even taller gears, looking for a solution to a non-existent problem. The problem is insufficient drain back from the heads/valve covers and has been discussed a million times. The simple solution is a bigger capacity pan.

 

X2 his post in this thread to fit an Aviaid pan or similar.  I've got an Armando pan on my 401 (very similar to the Aviaid as Armando used to work for them).

http://aroilpans.com/Roadrace.html" rel="nofollow - http://aroilpans.com/Roadrace.html

http://aroilpans.com/images/AMC_2.jpg" rel="nofollow - http://aroilpans.com/images/AMC_2.jpg

 

Hope this helps,RD

Thanks for the reply Rebel Machine!

I just checked my new summit camshaft and comp cams timing gear, it seems to be covered enough that I shouldn't have any problems. but hear are some pics to get your opinion...

https://flic.kr/p/2etdsoP" rel="nofollow"> https://flic.kr/p/2etdsoP" rel="nofollow - AMC cam and timing gear passage clearances. by https://www.flickr.com/photos/163232977@N08/" rel="nofollow - David Cruz , on Flickr

https://flic.kr/p/Sk7cyJ" rel="nofollow"> https://flic.kr/p/Sk7cyJ" rel="nofollow - AMC cam and timing gear passage clearances. by https://www.flickr.com/photos/163232977@N08/" rel="nofollow - David Cruz , on Flickr

-Steve-

Thanks Steve. And yes I lined up the slot with the oil hole or whatever it is called. @73hornut

David. 

I have also used this to adjust oil pressure if there is too much after a new build before starting

 

Um, Not!    The extra quart is still below the baffle in the stock pan.  The oil level is far below the baffle in a running engine and at no time is the crankshaft spinning in the sump oil.  A full quart or more is trapped in each cylinder head and another in the lifter galley during higher speeds.  This leaves only two in the pan.  I have run many engines on my start stand and sometimes use slotted valve covers during valve adjustments on running engines.  The oil level during 2000 rpm cam break in is usually an inch or so in the heads and much more at higher speeds.  I have NEVER witnessed any foamed oil in the heads of a running engine.  But this is with just limited AMC experience.  I've only built about a hundred!

 

Sounds right to me and I trust hands on experience over theory any day. So my question is would you think its better to run a higher capacity pan or is it fine to just run six quarts of oil in the stock pan?

T/A performance. Its a Buick part and the bolt is a different size so I transfer the adjuster to an AMC bolt by drilling the same size hole and using an AMC spring

Trader has a few things correct -- aeration/frothing of the oil is bad, the extra quart allows more "spirited" driving, and the stock pan with stock oil level is good for everyday driving.

69 ambassador 390 has the reasons the extra quart works correct, and is also correct that even on startup with all oil drained in the pan six quarts won't contact the crank, at least with the car near level. I suppose it might if on much of an incline, but even then only for a second or two until the pump sucks it up into the engine -- by the time the engine fires it's sucked up half the oil.

For regular racing a high capacity pan may make sense. For the occasional trip down the strip or autocrossing the extra quart has proven to be more than adequate. I'd only invest in a high capacity pan with a "floating" pickup only on a high dollar race engine (or any high dollar build). Well, $5K is "high dollar" to me, but what I mean is those $10K+ engine builds. $5K gets you what, a mild but well built engine -- at least if you have a good shop build it. Plenty people on here could build a healthy street/strip engine for $5K or less. Really depends on what you start with and just how "healthy" you want it. And how good/licky at parts scrounging you are. I think I could build one (assuming I started with an engine in decent condition) with all new parts for $5K easy enough.

 

... if the engine has sucked up half the oil shortly after it's fired, not surprising we have never ending oiling issue threads :)

 

Also, remember that the engine is angled down approx. 3 degrees in the chassis, so when doing the "extra quart" test, make sure the pan is at a 3 degree down angle to simulate start up.  Then if half the oil is sucked out of the pan shortly after start up, lower the level by half then angle the pan 30 - 45 degrees forward, rearward and side-to-side to simulate braking / acceleration / cornering oil levels (45 degrees being 1-g load) ... and check if the pickup is generously submerged in oil under all conditions. 

 

Then consider your application and whether the stock pan with 5 quarts or 6 quarts is enough. 

 

Hope this helps, RD.

https://pdfs.semanticscholar.org/0270/899b3d94e43389f53d451e4fb00cfe32e5c4.pdf" rel="nofollow - https://pdfs.semanticscholar.org/0270/899b3d94e43389f53d451e4fb00cfe32e5c4.pdf

I find figure 1-5 and connecting rod lubrication interesting as it seems to me a plausible cause for #6 failures and typical AMC failures towards the rear due to "bubbles forming and blocking oil flow.

Shawn

As RD pointed out the aggressive driving is another matter.

On deceleration the "police pan", you would think, without the "standard pan" baffle, move so much oil to the front of the engine that you would aerated heavily but also expose the oil pickup to air.

I'm not convinced the "police pan" is a desirable thing to have.

Just reading on the g forces, a stock 1970 Go Pack AMC by the numbers (time/distance) would pull 0.4g on acceleration and with disk brakes was best in class and pull 0.6g braking.

Not bad for a 1970 vehicle, as a BMW M3 today is best in class pulling 1g (32 ft/s-sq) braking.   

Here's the link you were asking about

http://www.taperformance.com/proddetail.asp?prod=TA%5F1502" rel="nofollow - http://www.taperformance.com/proddetail.asp?prod=TA%5F1502

looks like they cost about $20

I was wondering, cause T/A Performance sells oil pump gears for Buicks, if the Buick gears are a bit larger than AMC gears, and if so, could the oil pump housing on an AMC timing cover be bored to fit these larger gears, thus making all those used housing with grooves in the oil pump bores, much more re-useable?

1. Run 100% filtration.  Not sure I'm there yet.  Yes, the housing bypass was eliminated with late engines because it was unreliable.  But did they concurrently switch to a filter with integral bypass?  If so how did the filter's integral bypass pressure compare to the one eliminated from the housing?  Maybe the same.  Lots of modern filter have an integral bypass that opens at single-digit psid.  Hardly any modern filters open at pressures less than 20 psid.  But this is differential pressure, not absolute pressure.  So if your gauge reads 60 psi you may still only have 5 psid across the filter bypass valve (so still closed).

2. Eliminate the housing bypass, use a modern filter with integral bypass.  Which filter should I choose?  What bypass psid is best?  Unless I'm using a high volume pump (I'm not), or starting with a filter that is restrictive when new (I hope not) then I dont think it matters much.  If your filter differential pressure increases significantly then your bearings already lost the battle.  Effectively maintaining oil flow while collecting all of the bearing bronze and lead probably isnt a winning strategy.  The important thing (my opinion) is that you KNOW your bypass hasnt been blocked open by chunk of rogue RTV for the last three oil changes.  Unless your engine is shedding massive bits of itself a little bypassing here and there wont hurt anything.

3. Here's what I think I'll actually do.  Block the bypass in the housing.  For initial break-in, and for a series of rapid succession filter changes (like four in the first day) I'll run filters with NO internal bypass so I provide maximum flow of 100% filtered oil because my engine WILL be shedding bits of break-in debris.  After that I'll switch to a high quality filter with internal bypass.Perhaps I'll compare my measured pressure at the gage for each style of filter so see if it seems like my filter is bypassing at high RPMs. 

But after reading a Smokey Yunik article in a 1980 Hot Rod Magazine

I'd probably look into a remote oil filter mounting with 2 filters

to reduce oil flow restriction / back pressure through the filter(s).

An I'm unclear on what Filter the "new" late model Mopar Filter Fitting fits...

The "new" double threaded piece that the filter screws to.

The Mopar adapter fits the Motorcraft FL-1A filter and others as well, anything that matches to the FL-1A.

Sure you can... just a little spray paint...

Nice touch!

 AMC V8's used several different oil pan pick ups. The one on the left is good as it is 0.050" heavier tube, better concave internal screen, no hole on top, but the extension if not removed actually goes into the block oil passage and cuts off 1/8" or more of the pickup passage.

from the 1969 Car Craft Magazine 4-part Article 'AM Si, Junkee No!' about where Car Craft

and Vic Edelbrock built their own 'clone' 1969 Hurst Super Stock AMX 390 car, motor and all.