Hi, new to the group, happy to be here. When going up a long grade at 65-70 mph, my 87 gradually starts to slow down. If I give it more gas it slows even more but is OK if I let up and then accelerate at the crest. From a standing start going uphill or trying to get out fast in the flow of traffic, it does the same until top or until about 45 on the level. "Passing gear" is worse. Haven't noticed any smoke while dodging trucks. Have a bad cat, cracked exhaust mainifold, and the PO cut the fuel filter out of the gas line, if those mean anything. Sorry to be so long but locals can't help and I need my ride. Thanks for ideas.