My exhaust port divider came loose and was ratteling to the point where it was no longer enjoyable to drive the vehicle. I had used POR 15 high temp epoxy to set it in place. It held it in place for about 4,000 miles. Last week I removed it and I don't have any numbers to prove the horse power loss, if any. But I have run a tank of gas through it, about 350 miles of normal driving on the same roads I normally do, and the gas milelage is the same. Also seat of the pants tells me there is no power loss.