Swap the injector with another one and see if the misfore hops to thaqt cylinder. Free way to check if its good!

 

The #8 cylinder/injector lean condition sounds like it could be your problem. Socha_62 has a good idea you may want to try before you order an injector[swapping with another cylinder]. When I installed the 24# injectors I just reset my computer, I did not have to reprogram it. I am running Vortech's T-Rex inline fuel pump rated at 43 GPH@70 psi in conjunction with the stock fuel pump in the tank although I use the Fuel Management Unit from Vortech also. I think you can run the set up like mine up to 9 or 10 psi,after that you would need a different fuel tank pump-but I'm not positive about that, I only run up to 6 psi and rarely hit that [I don't get on it much,he**,about the fastest I've even had it up to is 85]. No doubt about it, a built up bottom end is better than the stock one.The oem head gaskets can be more of a problem under boost than the bottom end from what I've seen [assuming the bottom end is in good shape],Cometic MLS or Fel Pro 1008's are better. I am running a completely stock bottom end [Fel Pro head gaskets] with a 112,000 miles on it and have encountered no problems,other than blowing out the lsd clutch packs in the rear end one day wheeling,but as I said before, I don't run that much boost and I don't or haven't ever raced it, no sense in it, 4wd and heavy. For my application, the supercharger is great for fast power in the mud,sand or climbing hills, 4lo blows people away when they ride in it 4 wheeling. If you have some bad injectors you can get the 24# FMS for around $230, flow matched for around $330 [for 8 of them].Probably cheaper than a new set of oem's. Let me know what you find.