The ultimate spark efficiency cable for the Aston range, Formula Power, is specially designed for racing and extreme conditions, operating from A typical power drop is 1 to 2% compared to a standard 15 to 18% cable. SEE OUR POSITIVE COMMENTS WHICH ARE MAINLY FOR LEAD SETS. SEE OUR SHOP FOR FUEL CAT PRE-COMBUSTION CATALYSTS SAVES FUEL - REDUCES EMISSIONS - LEAD-FREE CONVERSION. If there is a problem with your purchase or if you are not satisfied with your purchase, please contact me immediately so that I can resolve the issue. If you do not find the set you want, please contact us.