Oil recommendations to use in a 427?

[Shawn W.]

Have been doing some research about the best oil for flat tappet cams and quickly found myself reading over 1,000's of opinions but little data. Some suggested using a 20W-50 off road oil because of the zinc level. Another recommend using a synthetic and adding ZDDP, and another recommended just going with a synthetic. Rather than dig through more opinions I figured I would seek the expertise of NCRS members. What say ye?

While I am at it, does anyone have any suggestions/recommendations about using an oil additive like Z-max in an older motor?

[Michael W.]

Re: Oil recommendations to use in a 427?

Duke, be gentle. He's new here.

Shawn-

read this starting on page three for some real facts:

http://stlouisncrs.org/news_files/St_Louis_NCRS_Chapter_July_2011.pdf

Zmax at best is of no benefit and uneeded and at worst the ultimate example of snake oil.

[Michael J.]

Re: Oil recommendations to use in a 427?

Duke, be gentle. He's new here.

Shawn-

read this starting on page three for some real facts:

http://stlouisncrs.org/news_files/St_Louis_NCRS_Chapter_July_2011.pdf

Zmax at best is of no benefit and uneeded and at worst the ultimate example of snake oil.

+1, only at break in of a new motor would you need more ZDDP than in the recommended oil.

[Duke W.]

Re: Oil recommendations to use in a 427?

Duke, be gentle. He's new here.

Hey, I'm letting you guys respond to these oil inquiries, now, and your response is spot on. Thanks!

Duke

[Shawn W.]

Re: Oil recommendations to use in a 427?

I appreciate the quick response and education.

[Michael J.]

Re: Oil recommendations to use in a 427?

It's really pretty simple, except I am always amazed at the people who don't know. I had one of my old cars at my friend's shop (an NCRS member and as old as I and has owned and worked on many C1-C3 Corvettes and an experienced mechanic for old cars), and told him to change the oil and filter. He looked at my Shell Rotella 15-40W CJ-4 oil and said, "you don't need to use the fancy synthetic stuff, any 10-30W will work fine". I had to explain to him too.

[Paul H.]

Re: Oil recommendations to use in a 427?

Z Max is Snake Oil. Save your money.

Shell Rotella 15W 40 will work fine. Walmart sells it cheap.

[Duke W.]

Re: Oil recommendations to use in a 427?

Walmart's house brand 15W-40 CJ-4 is less expensive than the national brands, and I will buy it if it's in stock at my local Walmart, but often it's not on the shelf.

Duke

[Ronald F.]

Re: Oil recommendations to use in a 427?

So would Delo 400LE 15W-40 be a good choice for the '67 L71 engine? And would use of these CJ-4 oils still require changing the oil every 2 months or could we go longer?

[Duke W.]

Re: Oil recommendations to use in a 427?

Yes, That's a CJ-4 oil... says so right on the bottle. right?

You change your oil every two months? My God, where does this stuff come from?

Duke

[Michael J.]

Re: Oil recommendations to use in a 427?

Wow! Every 2 months? Mine is changed every year, whether I need to or not.....

[Pat M.]

Re: Oil recommendations to use in a 427?

We need a "Here's what oil to use in your vintage Corvette" permanent sticky.

[Ronald F.]

Re: Oil recommendations to use in a 427?

Duke, it says so right in the original owners manual: Every 60 days or 6k miles. It's confirmed in the Service Manual. I know...I had to check it 3x before I finally believed my eyes. Apparently, the L71 is prone to producing acidic oil during cold starts. It also calls for 10W-30 oil which is why I'm wondering if the 15W-40 viscosity oil would be OK.

I have been using non CJ-4 oil, Castrol 10W-30, for the past year. I drive it weekly if weather permits. I could use some expert, experienced advice, particularly from other vintage solid-lifter engine owners.

Ron

[John M.]

Re: Oil recommendations to use in a 427?

I had my 67 BB at Hendrix Performance shop, while there they did a oil change and used the Mobil 20W-50. I think I'll stick with that recommendation next time I change the oil.

[Robert M.]

Re: Oil recommendations to use in a 427?

Have been doing some research about the best oil for flat tappet cams and quickly found myself reading over 1,000's of opinions but little data. Some suggested using a 20W-50 off road oil because of the zinc level. Another recommend using a synthetic and adding ZDDP, and another recommended just going with a synthetic. Rather than dig through more opinions I figured I would seek the expertise of NCRS members. What say ye?

While I am at it, does anyone have any suggestions/recommendations about using an oil additive like Z-max in an older motor?

Shawn

Read Duke's many posts on this subject. Follow his advice and save your money.
Rob