Recent ( 1st) oil change on the roadrunner. Should I add a zinc additive?

It all depends on what you used already. If it was just typical conventual oil then yes. This is what my engine builder recommended and what I use.

I used that on intial oil when engine was built. I just did oil change .( aprox 500 miles) Penzoil synthetic 10W30

I use the Lucas 10W-30, has enough zinc for FT cams.
There are a few different but similar performance/FT oils - Driven, etc - if you prefer.
With regular oils, I've been using the old GM EOS additive, but I'm down to my last bottle.

I use Valvoline VR1 10x30wt. it has high zinc, no additives needed

Same here, VR1, 10/30, for 10 years on our FT
Last look at the lifter and lobes, excellent...

Joe

x3

I used a full bottle of GM EOS to break-in an engine years ago, and also add about a 1/4 cup or so of EOS in with the normal oil change since then. This was during the time frame where oil manufactures were removing the good stuff from oil so I figured some additive just in case was better than none at all.

It's a daily driver engine with a real mild camshaft fwiw. If was something stouter for a weekend fun car I would look at a more performance oriented oil without having to use an additive most likely. Old car driving season here is only so long and one oil change per year will do just fine even if the oil and filter was more money for the good stuff.

I use VR1 also but if your build is roller cam setup why worry about zinc?

I think the problem is oil advertised today as "high zinc" simply means that oil is at or near the legal limit, which I think is around 800ppm. Back in the days before all cars had roller cams I think the amount of zinc in oils was at least double the 800 ppm number. How much zinc does a flat tappet motor need after proper break-in? I wish I knew.

A lot of my buddies use Lucas Hot Rod & Classic Car Oil
https://lucasoil.com/products/hot-rods-classic-cars/hot-rod-classic-car-10w-30-motor-oil

Castrol GTX Classic has high zinc, 1400 ppm, and phosphorus and is available at Walmart for reasonable cost. It's only available in 20w50 though.

That said, I just run modern 10w30 oil in my 51 Plymouth, but it has wet noodles for vale springs and giant mushroom lifters.

https://bobistheoilguy.com/forums/t...ssics-castrol-gtx-classic-20w-50.339113/

Yes, I'd pour in some zinc additive to that oil. Next time use Valvoline VR1 or the Lucas hot rod oil so you won't need an additive.

Flat tappet cam or roller ?

I use Bradd Penn . I don't care for additives as I don't know enough about how the additive does mix and interact. I know people on here use it with great reviews. I also use the valvoline high zinc on flat tappet cars that I sell as it is at a better price than Bradd penn. Rumors out there that after Bradd changed hands that the oil is not the same . I researched and found out it's the same formula,different bottle.

If a roller cam...any oil you want.

I was told that if you add zinc to any of the standard motor oil that you can buy at the auto parts store it will not do any good. The reason for this is that the detergent in the oil is so many times higher than it was that it will just basically wash off the surfaces including the added zinc. If you have a flat tappet cam just run one of the oils that has the zinc in it like Gibbs hot rod oil, Penn or others.

Another option is the Mobil 1 high mileage 15W50- it's cheap at Wal Mart, usually $26 for 5 quarts, and has enough zinc for flat tappet cams. I've been using it for a few years now. The other Mobil 1 oils don't have enough zinc, but the 15W50 does.

https://lucasoil.com/pdf/TDS_Break-In-Additive.pdf


"TEST ASTM TYPICAL
ENGINE BREAK-IN OIL ADDITIVE
TB ZINC PLUS
Addition of 16 oz. to 4.5 quarts motor oil will achieve approximately 5,000 ppm of Zinc."

A friend of mine who is a big time drag racer recommends the Driven Hot Rod oil. I still use the old formula of Delo 400LE 15w-40 with a bottle of Comp Cams Oil Additive.

I run Valvoline VR-1 10w30 conventional in my car. What would happen if I switched to Mobil 1? Mobil 1 is synthetic.