novadude,
Valvoline has dropped the huge amount of Zinc they used in the past and now use newer ashless AW's and FM's along with a different anti-foam additive in their formulations. The oil has a good detergent/dispersent package that will run on the street well. All their VR-1 oils have a TBN of 12. I ran it in my Tow Truck for about 200k and all was well when sold.
Every State has some kinda VW/Porche guru
To try to understand how one of these motors can run a high VI oil FIRST they need to understand why both engine cases utilize a dual bypass in the oil system of a VW or Porsche Aircooled Motor and how they work. I would not use a 20/50 in these motors,actually I would use a straight 30,40 or 50 wt depending on the climate. A stocker typically holds 7 lbs of pressure with straight 30wt at hot idle with the oil light blinking
It has been too long since the last 450 +HP Autocraft based Turbo Drag motor I built but I believe they only used one bypass and it is adjustable via a threaded bolt,alot like the aftermarket offerings for both the dual bypass case and the pre 1600 VW dual bypass case.You can dial in the low and high pressure bypass .The Autocraft case was or is not a streetable piece though.
Gene Berg early on did write the book on modding the VW motors,problem is Gene is not around anylonger to keep up with new Technologies and of course others have built some motors to beat Berg stuff of the 60/s 70/s and 80's. A race motor builder is not King of the Hill long these days,,someone with more money will always come along and beat ya
And thats what it's all about,going fast costs,how fast do you want to go???
Are there still reasons to use a 20/50 in the USA in other engines? You bet! Depends though on engine design and how the motor is used though and too many variables to post..now ya'll can fire away!
[ February 08, 2003, 09:31 AM: Message edited by: dragboat ]