I know I'm gunna open up a can of worms here, but what would be the best turbo to upgrade to? I was thinking a hx40 but I'm probably wrong!!

 

I couldn't really tell you what turbo to get because i haven't had much experience with different turbos, i just ordered an s300 from scheid diesel which is supposed to be a good turbo, but i wouldnt get an hx40. Their shafts are the same size as a hx35 with just bigger fins which makes them very easy to break.

 

an hx40 will get you into the 13's for sure, but its not the best turbo to upgrade to. In order to determine what turbo is best for you, we need to what the truck will be used for, and what your plans are down the road, such as twin turbo's or faster 1/4 mile times. In my opinion your gonna hit 13's in the 1/4 and want to go faster, so i would recommend this turbo
http://www.scheiddiesel.com/display_part/1979.php

 

I guess its a slippery slope....I use the truck every day to & from work so it needs to be drivable. I don't know how much horsepower I need to achieve 13s but I was shooting for around 4-450hp

 

the driveability doesn't really start to drop off until 8 maybe 900hp even then with twins the trucks can be still be driven every day to work or wherever and back just depends on how many corners are cut. but 400-450 is good goal to shoot for if you wanna run 13's.

 

Billet output shaft? If you don't have one, I would rule out boosted launches which will make it a lot harder to get into the 13's. I'd stay away from DV's for now, and get yourself a set of 370 injectors, good and cheap, and 850hp has been made with 370's and 181 dv's. The best thing to do IMO would be to start by turning up the pump more. Switch the washers around the diaphragm in the AFC, and grind the foot of the AFC as well. Also get yourself a 2095 rack plug. These mods will give you full rack travel and cost very little.
If you can time it yourself, the rack plug and injectors will set you back less than $400, and the rest is free. This should get you there, but you'll start getting really hot. I'd throw a 62mm turbo in with that combo and you should be running nice in the low 13's time frame.
Sean

 

Thanks for the advice Sean 1 question though...will the marine 370's wreck my pistons? do I really need matching pistons? TIA

 

the spray pattern is a little wide on the 370's 155* vs 145*, so if you keep stock timing, it will over spray the bowl a little bit, causing the truck to haze at idle and smoke a little more than desired. However, this will not wreck your pistons. To keep the fuel more confined to the piston bowl, advance the timing a little bit, and/or run thinner copper washers between the injector and the head. I believe stock thickness is .020" and I ran .010" on my 12v. I also know people that ran without the copper washers and never had an issue, but that seemed a little too risky for me. They are there for a reason. Its pretty common to run thinner washers so they can be picked up at most diesel performance shops.
Sean
Sean