lifter noise? help

94 is pretty high octane. better than I have here (93 is the best here). I wouldn't expect the additive to help much. If you read the print most say it raises octane 3-5 points. That's true but misleading. It's misleading because it actually only raises it to 94.3~94.5 octane. The points they refer too are just that, points. Not actual full octane numbers, such as raising it to 97 or 98 octane. Hope that makes since as it was hard to write and get to come out correct. since you know what pinging sounds like I assume you don't think it's just pinging. At the same time if a lifter would actually be ticking I'm not sure you you'd hear it over the roar of the engine since you said you only hear it when your accelerating. That's why I'm inclined to think it's something else. Even in spite of trueing up the headers it could be them. check the collector gaskets like T67 said and if you don't find a problem there check the header gaskets again. Make sure the gasket is completely covering the sealing surface. I have a good header related problem for you. Last year I installed Percy's dead soft aluminum header gaskets on my Cuda and they didn't seal very well even after re-torque'ing them 3 times so I just left em go cause I'm planning on replacing them with Doug's or TTI's. Well after about 1000 miles of driving they seem to have sealed themselves up. Strange how it took them so long to seal. BTW: They made a ticking sound upon acceleration when they leaked so headers can do it.