1975 Pontiac 350 oil and additives

[Karnawgie]

This may come across as a dumb question but I figured you guys could help me out.

My 75 grand lemans is well over due for an oil change. It's been a daily driver and I drive it pretty hard everytime I drive it. I'm big on letting the car warm up until the coolant temp rises.

I ask about this because this is my first older v8 car, beside my 1988 350 suburban.

I've heard these older engines thrive on higher zinc oil or oil with additives and I'd like to hear what you guys suggest I run in it.

Would valvoline 10w30 and a zinc additive be sufficient? Thanks.

 

[melsg5]

Yes, that's perfect plus a good filter Wix/Napa Gold.

 

[avell007]

Summit sells Hot rod oil , not only has zinc but some other additives that prevent rusting inside the block during storage. The brand it Driven. $9.99 qt

 

[Godspeed Garage]

Zinc is a BIG NO NO if you still have a catalytic convertor. It will cause a coating in the catalytic convertor internals.

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[melsg5]

Appears the earlier cats it is not that critical and it's better than worn cam lobes.

Zinc oil with Catalytic converter - CorvetteForum - Chevrolet Corvette Forum Discussion

C3 General - Zinc oil with Catalytic converter - Hi all ,I have a 75 L48 stock motor. I been hearing some people saying you should not use zinc oil with a car that has a CAT . True or false. Thanks

www.corvetteforum.com

 

[Karnawgie]

My car is straight piped and does not have any cats. That is an interesting point though.

Valvoline's grey vr1 racing oil seems like a safe choice and I can get this for 7-8$ a quart as soon as tomorrow. Sounds alright?

This is a loaded topic and seems to come down to opinion for most people. Trying not to overthink it. An oil that's pre formulated with more zinc seem like a safe bet.

The Driven oil sounds good but I presume this things gonna need another oil change before I know it so the storage protection might not be necessary, plus I'm impatient.

 

[melsg5]

My car is straight piped and does not have any cats. That is an interesting point though.

Valvoline's grey vr1 racing oil seems like a safe choice and I can get this for 7-8$ a quart as soon as tomorrow. Sounds alright?

This is a loaded topic and seems to come down to opinion for most people. Trying not to overthink it. An oil that's pre formulated with more zinc seem like a safe bet.

The Driven oil sounds good but I presume this things gonna need another oil change before I know it so the storage protection might not be necessary, plus I'm impatient.

That's what I use on my older cars VR1 10W30.