Contrary to some bogus information printed in one of the monthly magazines, I do not sell and do not recommend the use of 1.2 or 1.25 ratio rockers on any camshaft except factory stock. If you are in question, please be clear that if a high performance cam grinder designs a new grind it will be made with the maximum safe rate of valve acceleration for the ratio rocker arms it is designed to be used on. He wants his cam to be as good or better than his competition's cam. That is likely the reason, at this writing, I do not know of any VW high performance camshafts designed to be used with these ratios. One exception to this (of course) would be (see below about stock cam) cams made for 1.5:1 ratio rocker arms and using a lesser ratio would be like making it back into a stock camshaft or at least reducing its effectiveness. If the rocker arm ratio is increased beyond the ratio the manufacturer designed the cam to run with, it will over accelerate the valve and make it impossible for the complete valve train to track, especially on the closing side. The valve train simply cannot keep up with this faster lift and fall. It is commonly known that the engine will run for some time under these conditions, however, what concerns me is that damage to the valve train will start to occur from the moment it is started. I am constantly called by people running the wrong ratio rockers asking for a cure of pulled retainers, bent pushrods, broken rockers, broken shafts, followers, guides, or seats coming out or loose, broken springs, even keeper grooves in the valve stems worn completely out, and on and on. Interestingly they do not think they have a rocker arm problem as they never seem to want to look at the cause, only the affect. All of these failures and many more are directly related to over acceleration and return rates which are uncontrollable by springs available to be used on any VW engine. There is one known exception, which is OK for the use of these rockers and that is the stock VW camshaft. Because VW wanted maximum reliability and was not interested in the HP output as much as longevity, they built in a very, very mild ramp angle so even our, GB 411-1.40 high ratio rocker set can safely be used. The only concern with our rockers would be the interference from the retainer to the guide on a stock head and the lack of spring pressure. |