Correct viscosity/additive package for solid roller cam+valve spring longevity?

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Sep 17, 2003
Carbureted 451 CI V8 application, .631" lift solid roller cam/lifters, 200psi seat pressure and 500psi open spring pressure. Car is driven on the street with an occaisional day at the track. Approx 80% street. Total oil fill is 8 quarts with filter. Bypass spring in the pump provides about 75psi hot. It produced 492HP at the rear wheels on a chassis dyno, so the motor is putting out somewhere around 600HP, give or take. If it matters any, the HP peak is around 6200 rpm or so. In an application like this where you have a good amount of spring pressure and fairly radical cam profile, will a thicker oil (say sae 50) do a better job of cooling the valve springs than a thinner (say sae 30) oil? Which would theoretically work better? In the same application, would a thicker or a thinner oil stand a better chance of reaching the roller bearings in the lifter? It seems to me that thicker oil might cling to the VS better and possibly carry more heat away from them because of that. Maybe [Confused] On the other hand, it seems a thinner oil might stand a better chance of lubricating the wheel/trunion/bearings in the lifter, just because it's more likely to penetrate that area w/splash. That would be a good thing, since that is a pretty highly stressed area, and there is no pressurized oiling available to it. maybe [Confused] But....... that's just how it seems when I imagine what's happening in there, and I don't really know [Confused] I'm using the 30& 50 numbers as theoretical thin/thick baseline numbers. If it makes it any easier, imagine the thin oil as 10x30 and the thick oil as 20w50. What is the correct viscosity for this motor? What brand has a good additive package for this motor? I have tried Kendall 40, Kendall 50, and Castrol GTX 20w50 so far, with no discernable difference in performance.... TIA, Rich
Is this a Mopar? What is the operating temp of the engine at idle, and at cruise? What is the cruise RPM? You have a big buck engine, and if it were mine, I would run a big buck oil. Probably redline 10w40 or 20w50. Most of the big blocks I have seen, don't care for 30 weights. Do you have any consumptions issues? Have you thought about working with Terry Dyson on your oil choice?
For $4.79qt. try Mobil 1 15w-50. Factory filled in Mustang Corbra R and used in Dodge Viper racing teams.
Thanks for the responses, it looks as if you guys are thinking a fairly thick synthetic is the way to fly? In the past I always leaned towards a conventional oil for this kind of car, mostly because of the rich idle that seem to come with the territory--the oil gets contaminated with fuel pretty quickly under certain conditions (a day at the track will do it, and also excessive 40mph and under use will do it) and it has to be changed fairly often because of that, and synthetic gets pretty expensive. Granted the fuel contamination might not be a problem, but when I can pull the dipstick and smell it...and it smells pretty strong.....I know it's in there. Some of the contamination does seem to burn off during a long highway drive though, so maybe I have been worrying/changing the oil excessively for nothing. Just trying to be safe rather than sorry. Gearhead: Is this a Mopar? Yes. .030 over 400 with a 440 crank. 4.375x3.75. What is the operating temp of the engine at idle, and at cruise? Oil temp? Unknown. No gauge! Guess I should get one? Coolant temp ranges from 160 to 210 if that matters any. What is the cruise RPM? With the current gearing, 3000 to 3500 on the freeway. That might change in the future though. You have a big buck engine, and if it were mine, I would run a big buck oil. Yes but I have a small wallet, because I spent all my bucks on the engine itself LOL. Just kidding there, but I would like to stay with something that is easily available at parts stores, and at least try to keep the maintainance costs down. Do you have any consumptions issues? No, none at all with either the Kendall or Castrol. Std tension rings/functional valve stem seals also. No smoke or other noticeable oil consumption. Have you thought about working with Terry Dyson on your oil choice? I don't know who Terry is. [Patriot]
Terry Dyson of Dyson analysis is one of our site supporters and active members. He has probably forgotten more about oil, than most of us will ever know. [Big Grin] You may want to do some UOA's of your oil and have terry help you with oil selection. I would probably go with a 40 weight. Sticking with a conventional complicates things. You may want to try a HDD oil such as rotella t or delo 400, etc. The schaeffer's blend would also be excellent, but I think it is about 2.80 a quart. I used to use valvoline racing, when I used conventionals at the track, although, from what I have seen here, I don't know if that was a good idea. I don't have any experience with Mopars but it sounds like you have a problem, if you are getting that much fuel contamination that quickly. Are you running rich thoughout the entire RPM range?
Thanks for the link. I like the idea of oil analysis. That might be something to look into for sure. For an engine like this, when should it be anylized? I change it whenever I think it needs it. There really is no set interval. Wait until I think it needs it, maybe? It's rich at idle and very slow speeds. Which, when I think about it, is where it spends most of it's time even at the track. It's a few minute drive to and from the pits for each run, + some warmup time before each run and all at low speeds. From 3800 to 6800, the dyno showed the AF ratio is only slightly on the rich side, at 12.5:1 with the exhaust on, to 13.5:1 with open headers. So it is pretty close to on the money at speed but rich enough to play it safe....but at lower speeds the cam and carb work together to make it rather stinky. Not enough to foul plugs or anything, just noticeably smelly in both the air and the oil. [email protected] is probably causing most of the low speed richness...
Originally posted by ZIPPY: In the past I always leaned towards a conventional oil for this kind of car, mostly because of the rich idle that seem to come with the territory--the oil gets contaminated with fuel pretty quickly under certain conditions (a day at the track will do it, and also excessive 40mph and under use will do it) and it has to be changed fairly often because of that, and synthetic gets pretty expensive.
Quite simply, without going to synthetics, the HDEO (Heavy Duty Engine Oil) 15w-40's will by far give you the best protection/performance: Chevron Delo 400 Mobil Delvac 1300 Pennzoil Long-Life ...At $6/gallon, they won't hurt your wallet as bad either when changed on a frequent basis. [ September 18, 2003, 09:16 PM: Message edited by: Jelly ]
Zippy; Notice how well the exhaust side works on the BB Mopars? Is that 266*@.050" on both? By the looks of your af ratio, you may have more exhaust duration than intake and the cam is ground on 106-108 sep. Rich exhaust/lean cylinder is common on BB mopar. I doubt on the dno you are making much HP over abut 6200-6400 RPM.
"Notice how well the exhaust side works on the BB Mopars?" There was only about 8 peak HP difference between open headers and w/the exhaust hooked up. So yes it must work pretty well! I goofed typing in the cam specs, it's a dual pattern, 262/266 ground on 110. Supposed to be an 'exhaust system friendly' cam, and from what I have seen it is. With the open headers it made 492 peak at about 6200, I ran it to 6800 on the dyno and it fell off to 430 HP at that point. It hangs on with the rpm reasonably well for an Edelbrock head motor, I imaginge a bigger port motor would like the rpm a little more than this one. No sense in shifting it any higher than 6400-6500 or so though. Only been to the track with this motor once, and had no end of chassis problems but hope to get it fixed up in the coming weeks.
Hey ya, Zip-Man, figured you'd be over here sooner or later! I've run my old 383 on Mobil One 15W-50 for 7-8 years now, consumption definitely declined from the 20W-50 and 10W-40 it had lived on for it's first twenty-plus years. A failed water pump -- and an ensuing 12-mile drive past that point -- sold me on it (though I have used synthetics pretty much exclusively since about 1982). Call that a default choice. DEFINITELY get yourself a supply of BALDWIN B2-HPG filters. They are rated for extended service, yet present very low resistance to flow; very important. I highly recommend to you the use of FUEL POWER if you're running non-race gas. It evens out, and improves the combustion characteristics of todays cat **** gasoline like nothing else I've tried. I also HIGHLY recommend the services of Terry Dyson. He has been a racer and is fluent in a number of the particular issues. He helped me get our 2001 Cherokee to post the lowest wear numbers I've yet come across. I'll post some links here you'll enjoy, and send you an e-mail with a little more. Just holler, and I'll be glad to share my experience. Some very knowledgeable folks here, and some time spent searching will give you a good overall picture. At this point, I haven't seen a lot pertaining to big old motors, but I'll bet that more will be forthcoming as this site becomes better known.;f=1;t=000443;f=24;t=000002#000003;f=8;t=000089#000011;f=1;t=003223;f=1;t=002298#000000;f=6;t=000048#000010;f=16;t=000264;f=16;t=000306;f=5;t=000580;f=8;t=000596;f=6;t=000256#000001 Also, do a search on here for "Pontiac 400" (The e-mail links honors the this sites rules.)
Here is what I was thinkin'; 262/266 110 .050" I 21/61 E 63/23 Most people can't leave well enough alone and advance their cams 4* crank. 262/266 110+4= I 25/57 67/19 I cl 106, E cl 114 Now by looking at the dyno sheet, you can see that BB Mopars do not need their cams advanced to make low end torque, in fact advancing cams generally hurts the overall performance of a race engine. The big Mopar is like a restricted engine. Too good of an exhaust port, but a small intake port especially for 450 CID. Reverse the above pattern and open up the lobe seperation to 112. Here is what you end up with: I 266 E 262 112 sep, no advance I 21/65 E 63/19 You likely have 1.5 rockers on a .420" lobe. By putting a 1.6 rocker on the intake side, you make the cam 6 degrees bigger at .200" With your cam, 262/266 110, a 1.6 intake rocker will make the engine think the cam is a 268/266. Overlap at .050" will hardly be affected by the rocker ratio change. Don't get your lash on the exhaust side too tight. Run the lash loose. With the advance out and 1.6 intake rocker, the engine will act like a 268/266, but operate like a 262/266. Your peak HP should move up to 6400-6500 rpm. One quick way of eye-balling peak HP rpm on Mopars is to look at the .050" intake valve closing point then add a couple of zeros. [ September 20, 2003, 01:50 AM: Message edited by: userfriendly ]
Hi Ross, I knew you were here too [Smile] Interesting input on the cam selection and rocker ratios and I do appreciate the thoughts. I don't really feel as if I have given it much of a chance though, one dyno day and one day at the track isn't much. Street manners are excellent as is, which is where it spends most of it's time, and for the time being I'm running the lash tight to try and avoid beating up the valvetrain. Plus it already has more HP than either I or the chassis know what to do I have to get used to it/take care of the problems before diving into the motor again. I am perfectly happy keeping the shift points low for now while the rest of the car and my comfort zone as a driver changes. I haven't put enough time into it yet to pass any kind of judgement, other than to know the car isn't ready and I am not ready. I just want to keep it alive as long as possible so the rest of the stuff can get taken care of. For more mopar-related tech, I highly recommend: To repeat the original questions: -Is there an oil that will have a positive affect on valvespring longevity in this motor? -Is there an oil that would give a longer life to the "splash fed only" roller trunions? -Are the two tasks at odds to one another, in terms of oil requirements? I read the article on sump temperature vs coolant temp where it says the oil basically does nothing to cool the valvetrain, however in practical experience on friend's cars they've noticed a difference in valvetrain life with street rollers. One friend claims a heavy, clinging oil will keep valve springs alive longer? True or false? On the other hand, I believe the roller trunions will be better lubricated with more splash, which to me means a relatively thin oil. True or False?
Sure you could fiddle with light engine oils for the valvetrain's sake and lose the rod and main bearings as a result. First of all, you don't put a .420" lobe on a roller cam add 500 LB valve springs, then start worrying about longevity. A street lobe of around .370"-.400" would have been sufficient. Then adjust lift and .200" duration numbers with rocker ratio changes. I'll assume you have an 8 3/4 rear end with leaf springs. That set-up is not going to handle 600 lbs of torque abd a 4000+ stall converter. After the 1-2 shift, your tires will spin again from the massive torque a tight lobe sep small roller cam in a BB mopar produces. Your A/F ratios gave away the tight lash theory. When you took off the mufflers on the dyno, did you bolt on 18-24" collectors? To win at drag racing, the car has to be predictable, repeatable, and reliable. I see you had lots of help from the experts on the Mopar forum getting you to where you are. Now putting all that torque to the ground is you next big challange.
...The only oil "trait" that would allow your valvesprings to last longer would be an oil that has a high amount of extreme pressure and boundary lubrication additives, which usually means phosphorus and zinc. Heavy-duty mixed fleet oils, such as Delo, Delvac, Rotella, and Pennzoil Long-Life have a higher phosphorus/zinc content level than "regular" oil. I also believe you need to run around at least a 40-weight oil, but only analysis will back me up on that one... That's all I have to say (for the second time [Big Grin] !) [ September 20, 2003, 05:27 PM: Message edited by: Jelly ]
Well, at least oil spray bars inside the valve covers since the engine would have oil restrictors with the roller set-up. Unless the rocker system has them built in. Think of it this way: If you bend a wire back and fourth it gets hot very fast. A valve spring has to open and close X amount of times per second at X rpm. That is the bending part that causes a spring to heat up. A roller spring may be a triple, or double with a dampner. To control harmonics and wind-up, each spring is wound in the opposite direction of the one next to it. The friction of these springs rubbing against each other X number of times per second also causes a lot of heat. One method of cooling the springs is to install oil spray bars that are attached to the rocker covers, another method is to build the rocker arms with oil holes directed at the valve springs. I'm sure all of the specific information for high performance Chrysler engines is available on the Mopar Q+A site posted above.
Originally posted by buster: For $4.79qt. try Mobil 1 15w-50. Factory filled in Mustang Corbra R and used in Dodge Viper racing teams.
Less if you buy at Cotsco, Sam's Club or go to Wally mart and get the 5 qt jug. Rick
Keep your reports coming Chunky .....I plan on running all 15W-50 on my Z28 soon. At this moment, I'm running 1qt of 15W-50, 350ml of #132 and the rest of sump capacity is 6qts.....I'm hoping for a very thick 30W to a low 40W with the above mix.
Z, when do you plan on having a UOA on this? I"m interested in seeing how the mix does. I might try it myself to bump up the 10w-30 more to a high 30/40wt.
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