small block oil galley mods?

[67furyfasttop]

Posted on Abodys. May not apply to many Cbodys but there's alotbof knowledge here so I figured I'd ask.

Not a mechanic but a mopar enthusiast.
Looking for opinions and experience with small block 340 high volume oil mods. A buddy and mopar guru says its been known to cause issues. The seller says it was done correctly. Im looking at a 10k car and dont want to inherit someone else's issue or be in over my head. Any feedback would be appreciated

 

[67furyfasttop]

Sorry typo. 340 engine!

 

[CBODY67]

As things have evolved, I've become more of the orientation that if some improvements are desired for a particular operational situation, then "high volume, standard pressure" would be the best option. IF the clearances of the moving parts are still "in spec", they will only need so much potential lube fluid. High volume won't help at all. High pressure might force a bit more into the spaces, BUT that could then cause issues related to "too much" being where a lesser amount is desired. I remember some "shade tree racers" claiming that a hi-volume oil pump "washed out" their main bearings, which always puzzled me as to how that might happen. But I also suspected that if they built their own race motors, it might well be "a user problem".

As to a "default mode", I'd consult the Mopar Performance Small Block Engine Race Manual to see what's in there. Possibly the Circle Track Race Manual, too? Although anything in there would probably be more specific to building durable engines for that particular application.

I also know that many "motivated" engine builders have devised some of their own "little things" to help things along, for particular uses and customers. And, many times, they will work for other applications, too. But you also need to understand what problem they were trying to address in the first place! IF your operational parameters aren't in that particular area, then it can be over-kill, BUT they (the seller) still wants more money for such things having been done.

So, what operational problem were they seeking to fix with these modifications? AND will you be using the engine in that mode?

In general, though, I believe that "high volume" oil was more needed in prior times, when the oil base stocks were not what they currently are. Especially considering that the oil cools and lubricates the surfaces. In other words, probably not needed as much now as in prior times.

Just some thoughts,
CBODY67

 

[67furyfasttop]

Thanks for input. I don't think think they were trying to fix anything. He had the motor custom rebuilt. Forged crank ect..
I've been told it doesn't really help or hurt and I'm not racing the car. I want a car I can drive an hour to a show or 2 and around town. He sent me pages from an old manual to better explain.

 

[3C's & a D?]

Thanks for sharing that information, I have never seen that set up. Looks like a high rpm race modification. Will it like loafing around 3000 rpm all the time? I can't say one way or the other. Could be no problem at all, but, as CBODY67 says -

will you be using the engine in that mode?

Also, given that it was built as a "race" engine there could have been other mods made, that may have made it a fuel hog.

 

[CBODY67]

There is NO problem with putting more oil to the mains, first. There is a way to restrict portions of the B/RB oiling system to do that, BUT consider why Chrysler would put more oil to the lifters, first, rather than the mains. And to possibly bias the oil system of the LA motor somewhat similarly.

The basic design of the B/RB engine is quite similar to that of the Chevy small block of 1955. The performance orientation of the Chevy small block (their only V-8 at the time) was to put oil to the mains first, then feed it to the hydraulic lifters.

Chrysler, on the other hand, chose to bias the oil flow to the hydraulic lifters first, then the mains. WHY? Consider the intended customer base for Chryslers (per se) being usually older and possibly with some hearing sensitivity decreases. They'd know that a ticking valve lifter would mean their engine was low on oil. So they'd stop in at the local filling/service/gas station and get the "young man" to check their engine oil level.

In other words, they'd hear a ticking valve lifter sooner than hear a "thump" from the engine (high frequency vs. very low frequency sound). My dad would always comment about the ticking valve lifters in our Chevy pickup, when the oil level was fine.

One observation I had in the '70s was that a small block Chevy that had not had stellar oil change maintenance would have a ticking valve lifter anyway.

Seems like the B/RB upper-end oil restriction was originally meant for use on racing-type motors? Most of which, when modified, would usually have solid lifters in them anyway. JUst as the Chevy V-8 race motors of that time, too. Even the 2x4bbl 283 "Duntov"-cammed motors. As higher-rpm hydraulic valve lifters hadn't been perfected just them.

DO check the cam specs on the motor in question. That could be one indicator of why some other things were done to the motor. Especially if it's going to need a 4.10 gear to work right!

We all tend to want a motor built "over-spec" in many cases, when Chrysler OEM-spec would be just fine . . . all things considered. Although some known, durability upgrades might be desirable.

Enjoy!
CBODY67

 

[Davea Lux]

This oil system mod was mostly used on race engines turning 6k+ rpms. It won't hurt anything at lower engine speeds. The question I would as is how much this engine was run at high rpms and how much is left of it. The steel crank and the heavier rods add to the low end strength as long as the engine was properly rebalanced after the mods were made. Adding heavier rods increases the low end mass so there is more strain on the rod and main bearings. That is why more oil is put to the lower end on racing engines. If this engine was built primarily as a race engine, it probably will have a relatively short life expectancy on the street, these engines are built to go very fast at the expense of longevity. Check the cam specs, if the usable torque range is above 3500 rpms, it is not really suitable for a street engine that is going to be a day to day driver. Will eat lots of fuel and be miserable to drive in traffic.

Dave