A lot of good info here. Get rid of the plastic cam gear for sure. A double roller timing set is always good. I agree 100% that oiling issues shall be addressed before much of the cam performance will be gained just due to the warm oil pressure falling so low the lifters can deflate. As for the distributor spring, I have had mixed results from that, it is sure worth an install for that money but save your old ones, as mine would occasionally pull in 35* timing at 1200 rpm and detonate like mad until it got close to 3k rpm. The distributor can be modified to some degree to get some timing curve and that can help tremendously with these engines. A 400 with a 4" stroke has a lot of piston velocity and My experience is it responds to timing more so than a 429-460 so timing is your friend or your enemy with this engine. Mine run best with as much timing as can be tolerated and with the auto mine took about 1* more than with the manual, without detonating. I am very happy with the crower products I have used. I would like to think a crower 15170 or a 15229 or a 15230 or a 15240 or a 15965 or a 15975 respective of how you would like your power curve. I like that crower seems to have slightly more duration for the lift they get making the ramps slightly less steep, effectively managing the thrust better as well as possibly enhanced lobe life, due to less steep of a climb all the time. I prefer the quieter cam while driving on hiway as well. Comps run noisy I believe due to the steep(er) ramps. That is a preference. Some people like the tone. An example would be a comp grind offering .520 lift on 270 advertised duration vs. a crower offering .510 lift on 276 advertised duration. This tells me the crower has a more gradual ramp profile. Finally is a cam upgrade with more exhaust duration than intake or "split pattern" as we call it.

 

I rebuilt my 400 in 2016 (almost 10 years ago now) and ran a crower 15975 cam if I remember correctly. Vacuum suffers slightly and off idle could be better. I would consider this a maximum choice for a streetable use heavy vehicle. and would go slightly milder if I had it to do over, however the mid range of the power delivery is truly amazing and my mileage is around 12 mpg with a 2barrel and factory exhaust manifolds. probably would increase with headers I would guess.

 

something i have noticed lately on ford motors with high miles, wiped out cam bearings, and by wiped i mean they had almost zero babet left between the pits , lucky in each case we were doing rebuilds as they either need to be out of the motor or carefully looked at with a bore scope , and they are oiled first than feed the mains and rods

 

That's why my engine was pulled back in July. I dropped the oil pan with a plan to replace gasket and replace front and rear oil seals. When I got the pan off, noticed babbit material in the bottom and decided to pull the engine. Found the cam bearings had delaminated. When I tore it down further, lots of copper showing on rods and mains too. It was certainly due for rebuild.

 

Has it ever had cam bearings before, or are they originals if you know? Was the cam wiped? When I dropped the pan in '23 or '92, I found nothing like that. I didn't even question cam bearings, they are OEM. was just an inspection and rolling in new rod & main bearings.

Wondering what oil you run.

 

I don't think the engine had ever been rebuilt before. Still had nylon timing set, stock bore, stock bearing size. The cam and lifters looked okay when I took them out. I wouldn't have ever suspected anything until I saw it in the pan. The oil psi gauge in dash showed within range, it ran okay, no strange noises. Only reason I dropped the pan was to fix oil leaks to get me by another year or two. I planned to pull the engine at some point but wanted to save a few more pennies and get a few other things done first before I did that. Finding bearing material in the pan changed all that.

I know this truck sat for at least a decade prior to me getting it, and from my understanding the person I bought it from had been trying to get it back on the road before he fell ill and it sat until I bought it. The story I got is they found it "in a barn" and that it had been sitting about 15 years when he picked it up from presumably the original owners based on other paperwork I found in the truck. Based on what I have found going through it, I am confident that story is close to accurate and it sat for 25 years of its life.

What I think may have happened, when the PO got it running when they pulled it "out of the barn" I don't think they prepped the engine properly after it had sat for 15+ years. Might have just thrown a battery in, fresh fuel and started cranking on it. I am thinking a dry start up after sitting for years cause those bearings to delaminate like that. If it didn't occur then, it's when the PO asked someone to sell it for him (who I bought it from) and same thing, after sitting for 10 years wasn't properly prepped for fire up. Regardless of when and who, it's fixed now. Machine shop installed new cam bearings for me when I had them do the rest of the machine work in August.

When I picked it up in Nov '22 I brought it home, it sat until weather warmed up and I started working on it May of '23. One of the first things I did, not knowing previous history, was dump some sea foam in crankcase, let it idle for about 10 minutes, then immediately drained the pan. My thoughts were, any sludge build up from sitting would get softened up by the sea foam and drained out. I put in 15W-40 Royal Purple diesel oil. That's what was in it when I dropped the pan. I might have put 500 miles on it between projects tearing it apart and replacing suspension, brakes, steering from May of '23 until July '24 when the engine came out. I have considered it was my use of synthetic oil and the sea foam that may have done that too.

Once it is back together and I have done my initial break-in and the first couple oil changes I will be using Castrol Classic High Zinc Oil going forward. You can get it pretty inexpensive from Amazon in 5qt containers.

Sorry to hi jack thread OP but thought it was worth sharing how you start with a plan and those plans can quickly change once you get into the motor and see what you're working with.

 

Could be you're right on the cause. They don't look hot. How did the cam bearing surfaces look?

 

The remaining surfaced looked okay, looked like the babbit just peeled off. The cam looked okay but, the gear for the distributor had a couple chunks missing from the teeth. I didn't see any abnormal wear on the bearing surfaces, lobes or lifters. The mains and rods were worn to copper in some places, but no gouges, no heat marks from any of them spinning. Though I picked up a 400 crank, I did have them inspect the 351M crank and it needed .010 under. That's why I bought the 400 crank from them instead. It wasn't much more to buy that compared to having them turn the crank. Very cheap way to gain 50 cubic inch was how I looked at it.

 

I had the same thing happen to my old 400 mtericson. Huge chunks of babbit in the pan. I think one of the bearings came out completely. Anyway, the rebuild got oil restrictors and a roller camshaft.

 

335 series suffer cam oiling issues in stock form dont they?

 

I don't think so, least not that I recall. I think "common knowledge" says was more a case that an excess amount of oil pumped to the top end was at the detriment to the lower end. The cam bearings really don't have a high load on them and as far as I ever knew ... most people replaced them only after a hot tank in the caustic bath. Maybe was a bad batch or an overheat episode that causes the delamination?

I don't know.... just speculating out loud.

 

Correct - the 335 series is not a "priority main" system. Two fixes are - a) limit oil to the cam bearings with special bearings from TMeyer or a restrictor kit from Moroso. And b) limit oil to the no.1 main bearing as it is fed from two places. I think this was just the result of making it a little easier to manufacture, but not certain about that. Racers will sometimes also bush each lifter with bronze bushings and a small oiling hole to prevent over oiling or loss of pressure if a lifter gets spit out in a major failure.

 

Thank you, I guess I had it backwards

 

Thank you all for your recommendations. It is very much appreciated