Is this your favorite?

 

That is the oil that I use. Some like Shell Rotella for diesel engines, some like Brad Penn, some like Driven. I'm not really sure brand matters as much as it does to make sure it has enough Zinc, phosphorous and Moly if you are using a flat tappet camshaft. A lot of folks on here use mineral base versus synthetic.

 

I do very few flat tappet builds, but the FT engines I do get the Lucas Break-in Oil for the run stand and I recommend it for at least the next oil change. There are other good oils out there like Driven or Gibbs, but they are also much more expensive. On this date, the Lucas is $31 for the 5 quart bottle at Summit which is about $6.20 a quart. A lot of the circle track racers in my area that have to use flat tappet cams never run anything else. Notice that Summit says "Race Only" which probably indicates it has too much ZDDP in it to be EPA legal - and that is a good thing. I also don't use additives with this oil since that would be a problem (and an unnecessary expense). Anyone know the difference between the Lucas break-in oil and their Hot Rod Oil?

Now if you don't have a flat tappet and have a roller cam this oil is still very good, but after break-in I usually swap over to a synthetic.

 

Race only could indicate that it doesn't have long term additives needed for a street driven car.

 

True, but then it would have the same problem as Valvoline VR1 which a lot of people run. At least the zinc and phosphorous levels are listed higher in the Lucas than in the current VR1.

Decades ago I ran VR1 on the street in an engine for over 30,000 miles. On a refresh there was a light coating everywhere inside similar to an ultra fine layer of soot. More like a slight discoloration of the surface that could barely be disturbed by running your finger across it. The shop owner attributed it to the micro particles settling out of suspension. No sludge and nothing more than that even in the bottom of the pan. Didn't find any additional wear so more of a visual annoyance.

 

That coating could have been corrosion. Race oils do not have corrosion inhibitors in them.

 

I've been using VR1, mostly the 10W30 and mixing it with the 20W50 version for the summer months.

 

Ive tried everything and it SUCKS!

My builder wants to use 10w40, but that weight isnt made in most of the high performance oils. Amsoil Zrod has it, but you can only get that oil through the mail, so if I need to add a quart Im screwed. Sure, I can order more of it, but it's nearly $16 a quart, and my setup already takes 8 quarts.

I finally found Valvoline Full Synthetic Motorcycle oil, made for sustained RPM's (over 10,000), corrosion, wear, etc

 

So you're looking for 4 stroke oil or car oil? Those could be very different. I'm thinking the add pack in a motorcycle oil would satisfy different needs than a car engine oil.

 

Summit has a 10w40 for flat tappet engines. I don't know where or who makes it for them. If it's Asia, it's probably soy sauce with a wave over of zddp.

 

Army, VR1 also comes in a full synthetic. Speaking for myself I have a concern about synthetic oils leaking. Maybe unfounded of course. I put that lightweight synthetic in my differential and thought I'd have 2 quarts on the floor. Didn't happen.

 

This is an old wife's tail that's loosely based on fact. If you put synthetic in an old sludged up engine, you may develop leaks. The synthetic oil was not the route cause exactly. The leaks were always there just blocked up with sludge. Synthetic oil has a tendency of solubilizing the sludge and removing from the areas where it was shoring up leaks. If you have a sludge free older engine and switch it to synthetic, nothing bad will happen. How light weight did you go in the rear diff? 75W 90 is very close to the old 90wt and you can get thicker if you want.

 

Only the best for me...

 

I've run all kinds of different oils in 8 years and can't tell if any one was better than another except for the pressure. Started with 20w50 because that's what Butler used in it originally then read that's to heavy then went to 10w30 but the valve train seemed a little noisy then to Rotella 15w40 for the zinc that everyone talked about even though I have a roller cam then people said it's for diesels not high rpms then to Driven 15w50 because my bearing clearances are larger than most then the pressure was to high (close to a 100psi cold) so now I settled on Driven GP1 10w40 synthetic blend.....because I have a roller. I still wanted some zinc of the dino and the properties of a synthetic so I think I have the best of both worlds now but idk, I'm just pretending to know what I'm doing but I'm good at throw shtuff at the wall

 

Baaad65, I'd follow Butler instructions. I tease about heavier viscosity oils but my car is basic. The 10W30 I use has a sound difference in 500 miles. Usually it has 5,6 or 7 passes on it so I'm always on the side of caution and drain it.