Seen a set of Webber twin DCNF downdraught carbs for sale to run on a 1600 leanburn CVH, with a 35tho skim, flowed head but standard cam and exhaust manifold, will these run ok, what else would i need to complete them and how much extra power would i be looking at say about 15hp also are they ok for realiabilty. Cheers BAZ