ZDDPlus

[Joe C.]

I have been using CJ-4 oil, such as Shell Rotella in my 1965 Corvette with L76 for a few years now, but I no longer want the higher viscosity 15W-40, because I plan on using a standard pressure relief spring in my oil pump. This engine will regularly see 7000 RPM operation.

I would like to use a multi viscosity oil with 30 as the op temp weight, which is not available in CJ-4. Prefer to use a 5W-30 with 10W-30 as a second choice (the engine never sees operation below 45 degrees F).

3.1 ounces ZDDPlus added to a 5 quart volume of SM oil will provide optimal zinc concentration of about .14.

http://www.zddplus.com/

[Larry M.]

Re: ZDDPlus

Joe:

There are other viscosities of CJ-4 rated oil available besides 15W-40, but you have to search a bit for them. If you want to do, go to the manufacturer's website and check what is available. Then find out where sold or who can/will order for you. Shell Rotella is available in 10W-30.

However, your alternative to add ZDDPlus should also work, and may be much easier.

Larry

[Joe C.]

Re: ZDDPlus

Joe:

There are other viscosities of CJ-4 rated oil available besides 15W-40, but you have to search a bit for them. If you want to do, go to the manufacturer's website and check what is available. Then find out where sold or who can/will order for you. Shell Rotella is available in 10W-30.

However, your alternative to add ZDDPlus should also work, and may be much easier.

Larry

Thank you.
Here is more information:

http://www.corvetteactioncenter.com/forums/c3-technical-performance/109893-shell-rotella-t-oil-flat-tappet-engines.html

[Jean C.]

Re: ZDDPlus

Joe,
Try Chevron Delo CJ-4 for the viscosity you want.
Best regards,

[Jean C.]

Re: ZDDPlus

Joe, sorry, I omitted the web site. Go to www.chevronlubricants.com.
Best regards,

[Duke W.]

Re: ZDDPlus

3.1 ounces ZDDPlus added to a 5 quart volume of SM oil will provide optimal zinc concentration of about .14.

A Zn concentration of 0.14% corresponds to a P concentration of about .0125%, which is the typical level in CI-4. CJ-4 has about five to ten percent less P and Zn - not enough to have any harmful effects on an OE valvetrain.

What kills lobes and lifters is high valve spring force and low engine speed such as lots of idling.

CI-4 oils are still preferable for off-road diesels (such as farm and construction equipment) that still use high sulfer fuel. Though most big city outlets now offer primarily CJ-4, CI-4 is probably common in rural areas that cater to the farm trade, and both CI-4 and CJ-4 are available in 10W-30. It's a matter of finding a retail outlet that can order it.

Walmart and Pep Boys have house brand 15W-40s that are still CI-4, first listed category.

Duke

[Lorne G.]

Re: ZDDPlus

I think it is a lot easier just to use a ZZDPLUS additive along with your regular oil. This saves a lot of running around and also lets you use a higher perforamance grade of oil if desired.
Lorne

[Duke W.]

Re: ZDDPlus

I think it is a lot easier just to use a ZZDPLUS additive along with your regular oil. This saves a lot of running around and also lets you use a higher perforamance grade of oil if desired.
Lorne

I think it's a lot easier to use CI-4 or CJ-4. You don't have to add anything to it! ...lower cost, less hassle.

Perhaps you can explain what you mean by "higher performance grade of oil".

Duke

[Joe C.]

Re: ZDDPlus

I think it is a lot easier just to use a ZZDPLUS additive along with your regular oil. This saves a lot of running around and also lets you use a higher perforamance grade of oil if desired.
Lorne

What kind of oil are you thinking about using?

Do you know that there are many "high performance" grades of oil which are blended with appropriate levels of ZDDP, including CJ-4 synthetic 5W-40, Amsoil synthetic, and various racing grades. The racing grades may have too much ZDDP added, and may not be suitable for everyday use. All of these are expensive at about $10/quart, or more.

I am pleased to know that I can special order 10W-30 in CJ-4, as most retailers don't stock it. That's the way I will go, as I have the peace of mind, knowing that the blend was concocted SPECIFICALLY for its intended use, and there will be no "conflicts" among components.

I was following Duke's thread re: WalMart's CJ-4 oil. I'll have to determine whether or not this can be had in 10W-30, as well. It does not concern me that it is reclaimed product.

[Duke W.]

Re: ZDDPlus

Walmart's SuperTech house brand is still rated CI-4, so it should have a little more (five to ten percent) ZDDP than any CJ-4s. I've never seen it in 10W-30, just 15W-40.

Clem says it is formulated from recycled oil. I don't know - maybe some of their oil products are, but not necessarily all. Someone asked if recycled oil must be disclosed on the labeling. I don't know, but I would think this should be the case.

In any event. To carry an API rating, the blend of base stocks must meet all the requirements including passing the tough anti-oxidation tests. The source of the base stocks is not relevent as long as the final product meets all the requirements.

Duke

[Duke W.]

Re: ZDDPlus

Most owners's manuals of the era say it's okay to use straight SAE 30 for cold starts down to 40F, but a multi-viscosity oil, like 10W-30 will flow better on cold starts. The "W" number represents a range of absolute viscosity at 32F and the higher number represents the viscosity range at 212F. So at 32F a 10W-30 has about the same viscosity at a SAE 10, but at 212F it has the same viscosity as a SAE 30. Most C-category oils are available in straight SAE 30, but are not usually stocked by city retailers.

I don't know what was factory fill in that era, but it might have changed with the season and was probably single viscosity. I think my SWC had SAE 20, and it burned off a quart in the first 500 miles. In the dead of winter they may have used SAE 10.

I recall that multiviscosity oils like 10W-30 became commonly available in the early sixties.

Duke

[Joe C.]

Re: ZDDPlus

everything, including my roller-lifter engines. I may be giving up some fuel economey, but I really like the way they don't 'rattle' on start-up they way they did with recommended 10/30.

As a curiosity, what was the factory-fill viscosity for a 65 Corvette?

Regards,
Dave

Hi Dave,

Attached is an image of the relevant page of the 1965 Corvette Owners Guide.

As Duke stated, I prefer to have the multi-vis for better flow at lower temps, thus I'd use 5W-30 if it was available. I like the idea of quick circulation with min. resistance during warmup.

I am ALWAYS concerned with fast coating of the cylinder walls after the engine has not been run in awhile. I am NOT going to build this engine with mirror finish cylinder wall surface by using a super-fine hone, as racers do, so I'll depend on a certain amount of oil retention on the walls before warmup. I am going to modernize this build in other ways, so as to minimize parasitic losses, such as by utilizing 1/16" - 1/16" - 3/16" rings on ultralight pistons, standard pressure relief spring for the oil pump, and other considerations. As far as piston slap is concerned, a high quality piston manufacturer in your neck-of -the-woods will forge a set of small domed pistons out of 4032 (eutectic) rather than 2618 (hypo-eutectic). The smaller expansion rate of this (comparable to FM's proprietary alloy) will allow smaller skirt clearances and minimal piston slap during warmup.

Joe

PS: Guess what? I'll be driving the red '85 across country for its (hopefully) Crossed Flags "coronation". Will I see you there? Aw, hell.........you'll probably be among those "perusing" my Corvette.

[Duke W.]

Re: ZDDPlus

The 4032 "high silicon" alloy is used for street applications and has relatively low thermal expansion characterisitics. The OE and FM OE replacement pistons are 4032 and can be fit at about .003-004" cold clearance.

The 2618 non silicon alloy is stronger and used for primarily racing pistons. It is stronger than 4032, but has a higher thermal expansion rate and needs to be fit at about double the cold clearance of 4032 pistons.

1/16" ring sets are usually "low tension" and should only be used in serious racing engines. A combination of thin low tension rings and loose clearanced 2618 pistons will cause high oil consumption in typical road use, may result in excess leakage at typical road load and revs, and are a poor choice for anything other than a dedicated racing engine.

Duke

[Larry M.]

Re: ZDDPlus

Most owners's manuals of the era say it's okay to use straight SAE 30 for cold starts down to 40F, but a multi-viscosity oil, like 10W-30 will flow better on cold starts. The "W" number represents a range of absolute viscosity at 32F and the higher number represents the viscosity range at 212F. So at 32F a 10W-30 has about the same viscosity at a SAE 10, but at 212F it has the same viscosity as a SAE 30. Most C-category oils are available in straight SAE 30, but are not usually stocked by city retailers.

I don't know what was factory fill in that era, but it might have changed with the season and was probably single viscosity. I think my SWC had SAE 20, and it burned off a quart in the first 500 miles. In the dead of winter they may have used SAE 10.

I recall that multiviscosity oils like 10W-30 became commonly available in the early sixties.

Duke

Duke and others:

The W rating for motor oils is the viscosity at 0 F and not 0 C (or 32 F). Those without the W are rated at 212 F as stated.

Agree with Duke that 20W-20 was the (generally accepted) straight weight factory fill during the early-mid 1960's. Not sure when the factories went to multi-weight.

During the 1960's when multi weight oils generally became popular, there were problems with the viscosity index additives not lasting very long. Many (self included) continued to run straight weights in their engines.....switching viscosity grades with the seasons.

Larry

[Joe C.]

Re: ZDDPlus

The 4032 "high silicon" alloy is used for street applications and has relatively low thermal expansion characterisitics. The OE and FM OE replacement pistons are 4032 and can be fit at about .003-004" cold clearance.

The 2618 non silicon alloy is stronger and used for primarily racing pistons. It is stronger than 4032, but has a higher thermal expansion rate and needs to be fit at about double the cold clearance of 4032 pistons.

1/16" ring sets are usually "low tension" and should only be used in serious racing engines. A combination of thin low tension rings and loose clearanced 2618 pistons will cause high oil consumption in typical road use, may result in excess leakage at typical road load and revs, and are a poor choice for anything other than a dedicated racing engine.

Duke

There are three basic types of aluminum alloy used for most piston applications.
Yes, 4032 (eutectic) has RELATIVELY high silicon content, as compared to 2618 (hypoeutectic), but low silicon content as compared to "hypereutectic" aluminum alloys. Eutectic alloys of aluminum, are those in which the alloy is "saturated" in its silicon content, and can tolerate no more before the crystalline lattice is no longer homogenous. "Hypereutectic" means that the alloy is "super-saturated" and the lattice is no longer homogenous. Eutectic and hypoeutectic aluminum are used in forgings; hypereutectic alloys are used in castings.

Characteristics of 2618 (hypoeutectic): Has lowest density, is more shock resistant, but not as scuff resistant. Has highest expansion rate, and can be forged. Best for race applications, especially those where nitrous or boosted intake pressures are used.

Characteristics of 4032 (eutectic): Has medium density, is less shock resistant, more scuff resistant, has moderate expansion rate. A similar alloy, known as VMS-75 is proprietary to FM, and is used by them in place of 4032. Ideal for normally aspirated high performance street, or street/strip applications where more durability is needed.

"Hypereutectic": Is state of the art for cast pistons. Has lowest expansion rate, highest density, and lowest shock (detonation) resistance. Best for street and medium performance applications.

The above explains why I will not use 2618 aluminum for my application. Production of FORGED, DOMED pistons for 327 with 5.7" rods (1.675 compression height) is extremely limited. I did not have an easy time finding a manufacturer who agreed to use the 4032 aluminum.

2618 aluminum contains silicon, but generally less than 2 percent. The eutectic point of aluminum is a concentration of about 12 percent, and typical 4032 (VMS-75) contains about 11 percent. Hypereutectic cast pistons generally contain between 16-19 percent.

1/16" thickness rings (as opposed to old fashioned 5/64" thickness) are not necessarily "low tension". They are designed to provide superior sealing but with less friction than 5/64" rings. It is important to have a perfectly round and very rigid bore when using these. Most modern engines no longer use 5/64" - 5/64" - 3/16" ring sets because they convert too much power into heat. Another reason I'm using 4032, is that I can install at minimum skirt clearance for better ring control...........preferably three thousandths. As a matter of fact, if I could get my combustion chambers small enough, I would seriously consider using flat top hypereutectics.