No one speaks about Lucas oils anymore, does anyone Have experience of The marine 20w50 or 20w50 racing? Rhode Have crazy ammount of zinc compared to others, over 3000ppm.

+50hp

Joking…..

Sure it’s all good.

Seriously…What ever makes you sleep st night. :thumbs

• Additive “over-treat” — too much ZDDP can cause film flaking and spalling, actually increasing wear.
  
• Can increase deposit formation on pistons and rings.
  
• Raises ash content, which can lead to fouled plugs and pre-ignition in high-RPM engines.
• 
  1,200–1,600 ppm is the sweet spot for most high-performance flat tappet and marine big blocks.
• 2,000+ ppm only makes sense for short-life racing oil (where engines are torn down frequently).
  
• 3,000 ppm is overkill unless it’s a specialized drag/nitro engine oil designed for very short runs.

Seems like a better choice :
Lucas Synthetic SAE 20W-50 motor oil (non-“Racing” / standard synthetic) has around 1,265 ppm zinc.

Night Be so thick that IT robs 50hp. 🧐

I am toi affraid of those high zing levels. Now i Have to decide between kendal gt1 20w50 vs valvoline vr1 20w50. I Would really want to try Mobil 15w50 synthetic, But we dont Have that here in Finland.

Dan, well said.

The largest issue for ZDDP (zinc) is the high levels of calcium (detergent) 3000ppm or higher. It washes away the zinc that is in the oil, trying to do its job. As Dan mentionend. 1200-1600 ppm zinc is optimal, and way better with a lowered calcium level to around 1000ppm.

800-900ppm zinc is a maintenace level zinc for already broken in FT cams. But it's also not enough for high pressure contact areas. Perf Marine BBC, almost every contact point is high pressure.

SP rated oils often have the reduced calcium, for direct injection engines. But you need an analysis info source to be confident your oil is doing what what you need.

Too much zinc...think thick paint...it will crack and chip off. Too brittle to flex. Same with concrete and metals.

Proper zinc levels will create more friction as it protects. Part of the process.

Many dyno tests for different oil viscosities. Once oil is at temp (210f-220f) there is minimal hp difference from 'thin to thick' oils. If anything, thinner oils will reduce HP.

Perf Marine engines are a different animal. Often sitting at 85% max for very long periods of time.

Not all engines are the same for windage and oil management. A properly setup BBC will have minimal oil entrainment in the crank.

https://bobistheoilguy.com/forums/th...7-1-5k.383225/

VR-1 20w50 1500mile oil analysis for a 2020 Harley.

Mentioned that the VR-1 conventional 20w50 was quiet on the top end, vs the synthetic was noisy...just like the Mobil 1.

Generally, using what you have available is the best COA...provided it meets your needs.

Kendall doesn't mention their curret SAE rating on their website. most info I've found for it is 10yrs or older. So no recent SAE package ratings...but have a look anyway.

JaniH,

AmsOil?

Thanks. Brad.

That looks interesting! I like synthetic oil heat resistance If there IS Any difference compared to quality mineral oil.