[cleatus12r]

Originally Posted by 907dave

For me the truck gets extremely loud during cold startup and easy driving even after extended idle time. I realize that the EOT is not up to temp yet which is why it is like this, but it really does not sound healthy at all. It has really concerned me. Keep in mind that I am running Hybrid injectors and know that it will never be as quiet as it was with the split's in there. I think you've realized the biggest issue. Yes, single shot injectors will inherently cause more combustion noise than split shots due to one big bang rather than the softened blow of two smaller injection events that makes a split shot what it is.So if I understand correctly if the truck is properly tuned when cold the idle and cruising noise levels should be similar to when the truck is warmed up? Not totally true, but the truck shouldn't sound like a 6.5L Chevy. If you've ever heard one of those, then that's what you don't want.And its possible that I can be doing more harm to the engine with this (advanced SOI) than I could be with it less advanced? Most of the time, this is the case. Later SOI will almost always be easier on the reciprocating assembly than earlier SOI to a point. Too late to the point of causing white smoke will wash down the cylinder walls with raw fuel and get rid of the oil barrier on the piston rings. It will also cause a severe lack of power, higer EGT (if a complete burn is accomplished), and just a waste of fuel.The white/blue smoke does not bother me much as I no longer have the intake air heater, fuel heater, or EBPV anymore and those all aid in reducing that. EPA probably wont like me much but I dont mind.

Ok, so how about doing the same thing (lessening SOI) on a warm engine to reduce engine noise. What adverse effects would that have. I would assume higher EGT's and poor economy, anything else? Would be nice to have a tune for city driving where economy and EGT's are nut much of a concern anyways.

Sorry, I am green at this and trying to get a handle on things.

I'm not sure what you have as far as tuning goes (Minotaur, FU2, etc.) but it's not that big of a deal to slightly retard SOI in certain parts of the maps but a trained ear is ALWAYS going to be better than a stab in the dark. Live tuning is a great tool in this area because you can change stuff while you're driving instead of making 6 different programs at a time and driving each one until you get a feel for them and then making tuning changes, erasing the chip, rewriting it, and then driving again.