OP, these guys have got you pretty well taken care of. "Safe" is a relative term and with the weak factory internals anything over factory power levels increses the risk of catastrophic engine failure, that's the unfortunate dilema we face. I'm a little more conservative than some guys so I recommend going with a 6# (9.0") lower pulley and retaining the factory (3.16") SC pulley. This will wake the truck up nicely. Porting the SC will net a few extra HP but more importantly, port the SC will make for a broader, more useable power curve. At the end of the day the power curve (how the power is made) is more important than "peak" power.
Of course you will need all supporting mods to include a cooler spark plug and tune. A MAF or MAF extender is a good investment if for no reason other than to avoid having to pay to retune if you decide to add one later.
Preventative maintenance is critical... replace the fuel filter every other oil change, clean the IC, and install an oil separator.
Gauges are also highly recommended, a wideband AFR gauge and fuel pressure gauge are the most critical.
Originally Posted by
Merlin
Most folks on here go with the 1999 - 2004 JLP Forced Air Induction Kit... is a true *Forced Air* Kit which draws Cold outside air...
Outside Cold air makes more power than HOT! Engine heat!
Why would you want an open air filter that draws hot engine air?
Regardless of the air temperature an engine needs air to breath and that is the benefit of an open air filter compared to the factory air box... reduced restriction and more readily available air supply.
The CAI debate has been going on for years. The advantages of cooler air charge is irrefutable but in the last decade I have yet to find anyone in the L/HD community that has been able to provide empirical before-and-after data that use of the scoop and tubing provided with any of the various "forced air" CAI provide any actual performance gains or drop in IAT 1 temperatures.
Additonal theories worth consideration that have debated regarding "forced air" CAI over the years:
1) in wet conditions there is the possibility for water to hydro-lock the engine - highly unlikely, yes. But this point has been debated
2) that the pavement (particularly asphault) retains heat, in many instances air temps at ground level where the CAI scoop is getting its air supply may be significantly higher than air temps inches/feet above
My personal experience and observations using a "forced air" CAI is that the one thing it did really well was cover my air filter and engine bay with road debris, grit and grime. I fully endorse aftermarket air box solutions (CAI, open-air filters) because they improve air supply and reduce restriction but IMHO the miunte gains of "forced air" aren't justified.