which oil for Ray Barton engine

I have a Barton 535 c.i. wedge. I run Lucas 20W-50 full synthetic "racing only oil". I have the oil analyized when I drain it and it has 3,000 ppm zinc in it! Wow! After 2 full seasons of drag racing the bearings etc. still look good. The same flat tappet cam has been used for 5 years, with no signs of wear. I do have a pre oiler system on the car. This must help a lot. In the 2 years, oil and filter changes are the only maintence done to the engine. The car runs 9.70's in the 1/4. As a matter of fact I'm going down to Rays shop this morning. (8 hr. drive) We're going to freshen up the motor and put a roller cam, gear drive and T&D rocker system on it. Ray has always talked with me on the phone, no problem. Nice HEMI engine you have there.