Regular or synthetic motor oil?

[pjbizjak]

I'm going to rebuild my 68 z/28 302 using new era parts; rings, bearings etc, and want to know if I should go with regular or synthetic oil.

[Jerry@CHP]

Synthetic is much more likely to leak.  The older engines were not designed for the newer oils.  I run it in my 67 Z Stock Eliminator car and there is always oil on the floor where the car sits in the trailer.  Leaks are the main issues.  Not performance.

Jerry

[jonboy1216]

try rotella 5w40 synthetic it works i run it in everything from my 68 rsss l35 car to my dragbike never had any leak issues with it. its made for big deisel trucks and is a real durable and stable oil and only 20 bucks a gallon.its been our secret in nascar country for years now. just use a good rear main seal and timing cover seal on your motor and dont cheap out on those parts.

[rich69rs]

I echo Jerry's comments.  Tried Mobil 1 for a little over a year in both my '66  Chevelle and my '69 Camaro.  After sitting for a few days there would be the inevitable small amount of oil that had dripped on to the gargage floor from both cars.  Went back to non synthetic 10W-30 and the problem went away.  

[click]

Ive had excellent results from using 100% syn, Amsoil in my 69 camaro, 350 LM1. It had been rebuilt with forged pistons, .30 over, balanced etc. The only area thats shows a few drops of oil is the rear main seal, which is common on so many engines. Rather than tear the engine apart for $$$  its no big thing to have a few drops of oil on the ground under my car, and still have the protection of better mileage, cooler running, less friction internally etc. Id take the engine protection, "insurance" of the syn anyday, over some very minor dribbles of oil.
Just my humble opinion

[LB68SS350]

I've had real good success with Valvoline Racing VR1. It's a conventional (regular type) motor oil with EXTRA zinc and phosphorus (ZDDP) and other friction modifiers, that these flat tappet engines need. I get mine at Advance Auto Parts, but it's available at others, like Pep Boys as well. Comes in 10W-30, 20W-50, straight 30, 40, and 50 weights too. I highly recommend it. Good Luck.   Larry

[tmodel66]

Ditto on the Valvoline Racing.  Been running it for 3 years with no hits, no runs, no errors, and best of all no leaks.

[BlackoutSteve]

Synthetic is much more likely to leak.  The older engines were not designed for the newer oils.  I run it in my 67 Z Stock Eliminator car and there is always oil on the floor where the car sits in the trailer.  Leaks are the main issues.  Not performance.

Jerry

Improve your seals Jerry I've used Mobil 1's 15W50 for years with never any leaks.
Far more consistant oil pressures and I'm sure better lubrication than mineral with the last pull-down where I put the same bearings back in.

[PANTHER-BUFF]

This is a hot topic for all with flat tappet engines. Take a look at the Corvette Forum discussions and some great info at bobistheoilguy.com.
 
http://forums.corvetteforum.com/c1-and-c2-corvettes/2485861-list-of-flat-tappet-oils.html

http://www.bobistheoilguy.com/

I've been studying for a couple of month's and decided to go with Valvoline VR-1 and a Pure1 filter(another hot topic). Both I can get from my local Advance Auto.  I also considered Mobile1 Sytnthetic 15W-50, available at the local Wally World. I have used synthetic before and I'm a firm believer. Like Jerry had mentioned, I have heard of people that have started useing and had trouble with leaking seals. Not sure of this, but I'm to lazy to take the chance.

Both oils have good zinc and phosphorus counts.....

Best of luck!    

Danny

[PANTHER-BUFF]

Anyone ever try Spectro oil? They claim a zddp of 1800!

www.spectro-oils.com

http://www.hargroveenterprise.com/