EGR
 

is there any downside to having an egr blocker plate or delete?

Not really. It's technically illegal, but your motor will love you for doing it along with a PCV reroute.

the plate is so easy to do, and its cheap

EGR blocker is the first mod you should do to an LLY IMO. It will throw a code but you can either tune it out, or throw a finger stick in there to take care of that annoying light on your dash!

Sinister Diesel makes a very flashy and inexpensive EGR blocker/delete. I think its in the ball park of $130. But like mentioned above, it is very benificial for your truck. I wouldn't say its the FIRST mod you should do, but it should be a high priority. definatly in the top 5 or 10.

(NOT IN ANY PARTICULAR ORDER) these are the top things i would change to ensure your truck lasts as long as possible........

Turbo MP(I like Kodiak but i depends on what you want),
PCV Re-route,
EGR Blocker with Finger Stick,
Stepper Motors in your gages (if they are going out, MINE ARE),
HD Tie Rods,
Intake w/Scoop,
Exhaust (i am just cutting the cat and muffler out until i get the cash for a full exhaust),
Tuner (i'm not looking for anything insane so i'm going with Bully Dog but most people say EFI LIVE, or BANKS 6 GUN with Monitor, Or PPE,
MP Resinator delete (if you are planing on having a MP with a res),
BD Exhaust Manifold (less restrictive than stock),
Deeper Oil, Trans, and Differencial pans,
gopurepower.com: reusible Oil, Fuel, and Trans Filters.

Well there are a few things you can look into. i would say about 7 of those things are under $200 (if you count the exhaust doing it my way {$160 at local muffler shop} and the EGR/Finger Stick seperatly) 3 are under $400 (counting the filters and pans individually it makes it 10) and the tuner can run you anywhere from $300 to $1500 (round about #) and depending on who you purchase from on the intake/scoop it could cost any where from $600 to $800

The way I understand it, an air intake only does so much. Yes cooler air going into the turbo helps, but you have to realize that the air that finally goes into the motor is cooled by air that has to go through the radiator before it has a chance to cool the intercooler. You can get similar if not the same results as an aftermarket intake by cutting the sides off of the lower part of your stock intake box and taking out the passenger side headlight.
3" intercooler pipes help with temps too. But by blocking your EGR you're keeping the hot exhaust gasses out of your intake track. Cooler, denser air= more power and efficiency.
I have the BD exhaust manifold too. Personally, I like it.
As far as tuners go, I'd say PPE or EFI Live. PPE makes good power and it can turn off the EGR codes, but I like my EFI Live for the ability to have switchable tuning on the fly with 5 tunes at once.
If you're going to do any kid of racing or run bigger tires, tie rods or sleeves are definitely cheap insurance too.

tuning, trans, intake, exhaust and sleeves. makes one fast truck :)

i say intake with scoop only because, yes you can cut your stock box(guilty, i've done it) but removing a head light for normal everyday driving is very impractical. and yes the air coming from your intake does have to go thru ur inter cooler before it gets to ur eng, but the colder the air is entering the intercool, the less the inter cooler has to cool it, and even may help lower the temp entering the eng. thats my 2 cents on that.

colder IAT make a big difference