Oil Recommendation GT 500

[Bulldog90]

I know the high zinc content anyone have any bias on brands - live in MS so does not get too cold here but warm in the summer.

[69 GT350 Vert]

If you have a roller cam, you don't need the high zinc oil. 

[vtgt500]

Oh boy......  Story time.

I purchased a new, unassembled side oiler in '78.  Was working at Ford in Livonia, so only natural Roush would blue print, balance and assemble it, and include his own oil pump. He did a tremendous job.  Ran flawlessly using Kendall 20W-50.  About 26 years ago it lost a head gasket due to detonation. The engine was torn down for a through inspection.  Wear was minimal.  Bearings and cam were near perfect.  A decision was made to upgrade the dated, Ford parts.  The Lemans rods got ARP bolts, new rod bushings and were resized.  Went .015 over for JE custom made pistons to suit the new, ported, Edlebrock heads. Valve train is a 294S grind with shell lifters.  Balance was fine tuned.  Rocker shafts and rocker arms are Dove.  The wrist pins, lifters and rocker shafts were micro polished with 1000 grit lapping film prior to Dicronite coating. After extensive research including extended conversations with oil industry chemists at the PRI trade show, Mobil 1 15W-50 was decided upon. In 25 years I have not had to adjust lash.  .000 cam wear.  Engine regularly sees 7000 RPM.  I could not be more pleased.

[csheff]

I use Amsoil, engine stays clean and have had no problems