1966 Dodge 440, RP 0w40 (SM), early check @1200 mi

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I know some don't put much stock in short interval UOAs, but I do this for fun/curiousity not money savings (my cars are my hobby).

Anyway, this is my '66 Dodge Polara, rebuilt-in-2006 440 v8 with 18,000 miles, first run on an SM oil. Disregard the silicon- I'd replaced valve cover gaskets less than a month before putting in this fill of oil. I did a UOA on a short interval because I was a bit concerned about a number of things- fairly fresh engine, old engine design, fairly high power/hard use, use of SM oil with a semi-aggressive flat cam, etc. and the elevated iron might tend to back that up, but its also still a fairly new engine and gets driven hard. I'll track the iron and see, but I've taken the precaution of going back to SL oil (RP 5w30). I don't put much stock in how an engine "sounds and feels" but I do think its got a bit less NVH on the 5w30, and I like the way the oil pressures run much better. I no longer see peaks over 85 PSI at high RPM, but I still see 25+ psi at idle- right where I built this engine to run- its made for lighter oil than heavier. I liked the way it ran on RTS 5w40 and would have run it again except for the much higher pressures. Don't like that much loading on the oil pump drive. I'm sorely tempted to try it on a 0w20, but I want to track the iron for a while first and make sure its still trending down. Interesting how high the lead shows in the universal averages for the 440- wonder if that's a lot of samples with leftover contamination from leaded fuel?

The other thing is that this is can serve as an almost-VOA for RP 0w40. Clearly its got more ZDDP than mainstream passcar SM rated oils, but I don't know that I like the fact that it doesn't seem to compensate for the lost ZDDP with a boost in moly or magnesium the way other SM oils seem to. Could be they're using a chemistry that doesn't show up on an elemental analysis, though. A lot of people say RP oils shear badly- this doesn't indicate much shearing to me. True, its a short interval but this engine should theoretically shred inferior VII packages: gear driven oil pump, high pressure/high volume oil pump that sends a lot of oil jetting turbulently through the pressure relief valve all the time, flat tappets, no rollers anywhere in the rocker train, and chain driven cam. I'll also hold out judgment on RP until I get a much longer run in on this load of 5w30.

Anyway, this is analysis more a for-your-amusement (and for my information) than anything else. Any other insight/speculation welcome.

D81184b.jpg
 
The zinc & phosphorus levels are less than I would prefer for a 60's era big block. Hard to tell if the iron is from anything abnormal, time will tell. You took the conservative route and went to an SL rated oil, that is a step in the right direction IMO.

Personally I would not use an SM rated PCO in this type of application. Someone in my local area recently had a fresh rebuilt-to-stock 440 in a late 60's charger wipe out a camshaft in less than 500 miles. The cam was broken in with the proper oil and additive, then the oil was drained and replaced with SM rated 10w30. Perhaps they did something wrong during the break-in process, but I wouldn't take any chances.

I would recommend a heavy duty engine oil, a 10w30 HEDO would offer a lot of protection and save you some cash.

-Regarding the universal lead average, I suspect leaded fuel as well.
 
I'd have liked to have seen a UOA with the 5W-40 RTS you were running. The iron is high compared to the universal averages, and you have very low miles on this oil. But, hard driven miles, I assume.

I'm dying to know the truth about ZDDP and flat tappet, and until I find out, I'm running 5W-40 Rotella-T Synthetic in my stock flat tappet 5.0
 
I would run a HDEO 15w/40. It will protect your engine better than the M1 for the above mentioned reason. I would say the SM oil is not the best choice for the application.But then I could be wrong but I doubt it.
 
Originally Posted By: Rob_Roy
The zinc & phosphorus levels are less than I would prefer for a 60's era big block. Hard to tell if the iron is from anything abnormal, time will tell. You took the conservative route and went to an SL rated oil, that is a step in the right direction IMO.

.......


It is an SM oil, not SL.
 
My 340 engine (rebuilt a few years before I bought the car) also sees some pretty high pressures. (Typically 45psi at idle, as high as 85 when getting on it.) I too worry about the high readings. This is with 15w-40 Rotella.

I'm tempted to try a 10w-30 next change to see if the pressures are reduced.
 
Originally Posted By: badtlc
Originally Posted By: Rob_Roy
The zinc & phosphorus levels are less than I would prefer for a 60's era big block. Hard to tell if the iron is from anything abnormal, time will tell. You took the conservative route and went to an SL rated oil, that is a step in the right direction IMO.

.......


It is an SM oil, not SL.


The oil that was run for the analysis was SM, I did go back to an SL RP oil after getting this result. We'll see how it turns out, but both analyses here and the RP website indicate that their SL oils should have around 1200 PPM Zn/P. I'm not married to Royal Purple either, but its super available in my area and if nothing else it generates discussion... ;-)

I'm not convinced the elevated iron is from "bad" wear, the engine's still only got 18K miles on it so if it trends down in the future, no worries. But it sure COULD be cam wear. I don't mind doing a little experimentation with this engine since I built it myself- the original numbers-matching engine in the other will get whatever pans out best from my experiments here ;-) If the cam wipes- lesson learned and I get motivation to buy a more modern, efficient performance grind... or maybe go roller ;-)

I wish I had run an analysis on the RTS too, but that was back before I found this site. I'd have no hesitation to run RTS if they offered it in a thinner grade. Hindsight being 20/20, I would have built the engine with full-groove bearings which combined with the HV oil pump and an Xw40 would be OK. But this engine really prefers Xw30 at the heaviest. The pressure relief valve goes to full open and the pressure *still* goes above the relief point at high RPM on RTS 5w40.
 
Originally Posted By: gd9704
My 340 engine (rebuilt a few years before I bought the car) also sees some pretty high pressures. (Typically 45psi at idle, as high as 85 when getting on it.) I too worry about the high readings. This is with 15w-40 Rotella.

I'm tempted to try a 10w-30 next change to see if the pressures are reduced.


The only thing that is at risk of outright failure from high oil pressure on these vintage Mopars is the intermediate shaft that drives the oil pump- I assume you know that there are two types of intermediate shaft for flat tappet cams: stock and hardened/heavy duty (the flats taper into the round shaft on most, but not all, HD shafts whereas the regular shafts have a sharp step-down between the shaft and the flats). I'm running the hardened shaft so nothing will go "snap," but consistent high pressure can wear the cam gear and the intermediate shaft gear (which could even be the source of my iron). If you aren't positive that whoever built your 340 used a heavy-duty IM shaft, it might be worth the hassle of pulling it out and taking a look. With a magnet and cleverness you can get it up out of the distributor hole. But getting it back in so that the ignition timing is can be set right requires finesse- not for the inexperienced.
 
Interesting and impressive that fuel is below 0.5% on this engine. Which carburetor is on this engine?
 
Originally Posted By: SubLGT
Interesting and impressive that fuel is below 0.5% on this engine. Which carburetor is on this engine?


Its an Edelbrock Thunder Series (new production Carter AVS) with electric choke. I LOVE the Carter AVS carbs, and the brand-new aspect is great- no worrying about leaky throttle shaft bushings, stripped threads, etc. like with my original '69 vintage AVS on the other 440 car. I ordered a strip kit the same day I ordered the carb and then I spent a good bit of time dialing it in. Not difficult, but I'm picky. Its never been dynoed for tuning, but I would change the carb and drive it for a week to see how I liked it, then make another small change and drive a few days... etc. I finally got it so that it drives about like an EFI car most of the time- the only time I really notice its a carb is first 2 minutes in the morning. Intake is an aluminum Mopar M-1 dual plane- which is basically a stock '67-'71 440 Magnum manifold re-cast in aluminum with smoother walls.

The only reason I was surprised at the low fuel is because another mod is that the exhaust heat crossover under the carb is blocked for better hot weather performance. It didn't really hurt warm-up either... of course my cars (except the Cherokee) never see a night below 40F since they're garaged in Texas. Warm weather forgives many sins of the carburetor....
grin2.gif
 
Ok, I haven't gotten any responses to my questions.

So let me ask one last thing. What do you think caused the higher than average iron wear?
 
Originally Posted By: 440Magnum
Originally Posted By: gd9704
My 340 engine (rebuilt a few years before I bought the car) also sees some pretty high pressures. (Typically 45psi at idle, as high as 85 when getting on it.) I too worry about the high readings. This is with 15w-40 Rotella.

I'm tempted to try a 10w-30 next change to see if the pressures are reduced.


The only thing that is at risk of outright failure from high oil pressure on these vintage Mopars is the intermediate shaft that drives the oil pump- I assume you know that there are two types of intermediate shaft for flat tappet cams: stock and hardened/heavy duty (the flats taper into the round shaft on most, but not all, HD shafts whereas the regular shafts have a sharp step-down between the shaft and the flats). I'm running the hardened shaft so nothing will go "snap," but consistent high pressure can wear the cam gear and the intermediate shaft gear (which could even be the source of my iron). If you aren't positive that whoever built your 340 used a heavy-duty IM shaft, it might be worth the hassle of pulling it out and taking a look. With a magnet and cleverness you can get it up out of the distributor hole. But getting it back in so that the ignition timing is can be set right requires finesse- not for the inexperienced.


440Magnum,

I did have the motor out once to repaint the engine compartment. (Leaky master cylinder ruined the paint.) While I had the motor out, I replaced the cam with a custom grind from Straightline Performance. The intermediate shaft is the hardened variety, so I don't worry much there. Yes, the shaft is a bit tricky to get in correctly!

It's nice to see some information and research regarding oil in our vintage engines. I've had my Demon for 12 years now, and it's been the best investment I've ever made. I hope to pass it down to my son when the time comes.....
bitogdemon.jpg
 
Originally Posted By: Jaymus
Ok, I haven't gotten any responses to my questions.

So let me ask one last thing. What do you think caused the higher than average iron wear?


I'm sorry, Jaymus- I typed up a response and then someone distracted me and I closed the browser before posting.

Whether or not the iron is from cam wear is really the $64 (closer to $300 actually...) question. It could still be because this is a (relatively) new engine wearing in. It could be the cam. It could even be shedding from the distributor/oil pump drive gears from the excessive load of pushing a 40-wt oil with an HV pump. Too many uncontrolled variables.

That's exactly why I went to a 30-wt SL specialty oil with known high levels of ZN and P (whatever RP's other weaknesses may or may not be). Eliminate that variable, then watch the trend over the next year. If iron just stays high, I'll chalk it up to a big, old-fashioned, hard-driven engine. If iron is trending down, I'll then do another short run of an SM oil (probably 30-wt non- HDEO like commonly availaible M1) and see what happens. If iron spikes back up, then I'll know its ZDDP deficiency. I'm trying to sorta document the question that's on everyone's mind: is lower ZDDP really OK for these engines. But with only a one-point measurment, I don't have ANSWERS yet... but I'm getting set up to maybe get some over the course of the next 6 months to year-and-a-half, depending on how fast I rack up miles.

-Steve
 
Originally Posted By: gd9704


440Magnum,

I did have the motor out once to repaint the engine compartment. (Leaky master cylinder ruined the paint.) While I had the motor out, I replaced the cam with a custom grind from Straightline Performance. The intermediate shaft is the hardened variety, sI don't worry much there. Yes, the shaft is a bit tricky to get in correctly!

It's nice to see some information and research regarding oil in our vintage engines. I've had my Demon for 12 years now, and it's been the best investment I've ever made. I hope to pass it down to my son when the time comes.....
bitogdemon.jpg




Whoah, that is a SWEET looking Demon! B5 blue? (nice JGC in the garage, too). I know I raised my daughter right when she started pestering me to pull my high-school car (73 Satellite 4-door) out of storage and fix it up for her instead of the Cherokee ;-) And its always to hear from knowledgeable Mopar guys. Sounds like you've got your bases covered and have the same exact situation I do- we know RTS 5w40 (and other Xw40 HDEOs) offer good protection, but its just a tad on the thick side for Mopar engines with high-volume oil pumps.
 
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