69 corvette not sure what grade to run...

[Cuda70383]

hello group. i'm new to posting on here, but been following since this site basically started, and now i decided to jump in for some feedback. i need this groups opinion. recently i purchased a 69 corvette, 350 thats been rebuilt about 1100 miles before my purchase. previous owner says that engine builder was from ga. this is what i know so far. the block is original, .30 over, brodix track 1 aluminum heads, victor jr 1" high rise, 750 no choke 4150, about 11:1 compression, no info on the cam though, and in cab timing adjustment. im just giving the rough specs on the motor, there's more specs if needed. apparently they put 4.56 gears in the back. so on the highway if i do go, 60mph is about 3200rpms. i definitely need to change that out

i did do the oil once, it takes about 8 or 9 quarts. [i supposed i could do a uoa on this run] i got to check the filter number, but its the 3 or 4 inch filter they were using, so i adopted that size. the last fill, i used castrol 5w50. with that oil, i seen the oil psi gauge peg 70+ and not even about 150 miles its pretty dark. i'm guessing they are using a high psi pump. i was wondering if to stick with that oil, or use a 15w40 for this motor? not sure whats the current high zinc otc oil recommended now. im still catching up on this site. i'm open to suggestions, i also can try to answer any questions about the car if needed to help narrow selections down. it doesnt matter if its dino, blend, syn, or hdeo.

thanks!

 

[panthermike]

I use a 15w40 HDEO in my mildly built 429. That's what I would use. I'm a believer in the extra ZDDP that the oil has over an SM/SN oil. I use whatever I can find the best deal on, currently Delo.

I could be wrong on this but I believe many 5w50's will shear out of grade anyways down to a 40weight. Not saying they're bad oils, but 15w40's are way cheaper, especially at 8-9qt capacity!

btw, sounds like an awesome car.

 

[Turk]

No recommendations without seeing the car...

j/k, kinda.

Yes, a 15w-40 like Rotella would be great.

 

[electrolover]

Rotella T5 10/30 or T6 5/40

 

[jdawg89]

And dump a jar of never seize in there for the xtra zinc...LOL j/k I had to

 

[Colt]

I had a show car '69 small block Vette for many years that I sold 4-5 years ago.Looked stock but I had the the engine rebuilt.I kept the old parts and added a high performance heads,roller rockers,cam,MSD etc.
I used Amsoil 10w40 and changed it once a year.
Probably would use Amsoil 10w30 or 20w50 Z-Rod high Zinc oil today.

 

[The_Jake]

I would use Brad Penn HP 10w30

http://www.penngrade1.com/Products/High-Performance/SAE-10W30.aspx

 

[mrsilv04]

Economical choice that will still provide good protection: Any of the Rotellas.... 15w-40 or 10w-30 in the white jug, or 10w-30 syn-blend in the silver jug. It's a good, stout oil for around $13-$16 a gallon.

Otherwise - browse the Amsoil catalog, I'd lean towards Amsoil AMO high zinc oil.

 

[another Todd]

QS Defy is a semi synthetic oil with high levels of Zinc. I would use that in a 5 or 10w-30 or 10w-40 weight. Available at Walmart for a reasonable price.

 

[oldhp]

QS Defy 10W30=1000 ZDDP
Qs Defy 10W40=1200 ZDDP

Another great Hot Rod oil is from Joe Gibbs Racing. Check'em out at www.joegibbsracingoil.com. They have many choices and great tech suport.

 

[aquariuscsm]

What about something like Pennzoil GT or Valvoline VR1?

 

[SS1970chrysler]

Delo or Rotella 15w-40 or even 10w-30 should do just fine.

 

[another Todd]

Here is a very good read on a corvette forum which shows zinc and other levels of about 50 popular oils and includes film strength tests. The tests somewhat surprized me. Lucky for me I happen to be using the highest film strength rated oil. Some conventionals beat out synthetics by a good margin.

http://forums.corvetteforum.com/c3-tech-...-test-data.html

 

[Clevy]

Originally Posted By: another Todd
Here is a very good read on a corvette forum which shows zinc and other levels of about 50 popular oils and includes film strength tests. The tests somewhat surprized me. Lucky for me I happen to be using the highest film strength rated oil. Some conventionals beat out synthetics by a good margin.

http://forums.corvetteforum.com/c3-tech-...-test-data.html


What was the testing criteria. At best the tester totally wasted his time. The 1 armed bandit tests a bearing race spinning against another. At best it's a pressure test and is not remotely close to being indicative of what really happens in an engine.
That test and the results are pointless. The oil is cold so it doesn't even activate the anti-wear agents,nor is there an anti-wear layer on the parts they are grinding against each other.
Put no stock in that testing nor its results. It is in no way representative of an engine.

 

[Cuda70383]

thanks for the replies...went to wally world and saw the t5 [thats the blend right??] for 16.00, delo was 11.97 and delvac was 12.97 [cant remember if the prices are backwards though]. if i do a uoa on the 5w50, theres going to be a lot of carb cleaner probably found in there. other than seeing the sheer, ill see if the motor is fully broken in. any reasons not to do the uoa on a 200 mile drop??

 

[Doug Hillary]

Hi,
Cuda70383 - An HDEO works well in these engines and Delvac 1 5W-40 would do the job well!