I am working on building a set of twins for my 2004 2500 QC 4x4 6spd. I have a lot of questions and would like any help possible. I have been working on this build-up for about a month with very little progress. I have run a SPS 66 and was very pleased with the upper RPM performance; however the driving RPM range was less than desirable. So, now on to twins. I want something I can tow with around 18k lbs and enjoy driving with some red-light to red-light action, just to scare the rice rockets.

Now, onto my truck it’s an early ’04 with the 305/555 motor. I have a 3850# Southbend double disk. Bullydog powerpup, TST PM3 with gauges, Edge EZ. Five inch exhaust and high flow filter set-up. 35 inch tires with 2 inches of lift. Weighs in at 8400 lbs empty.

First round of questions. What secondary should I use? I have my stock HY35 9cm exh. housing. I also have a SPS 62/14cm housing. If, I run the stock turbo what size external wastegate should I run?

Second, what primary should I run? I keep hearing about the BHT3B and would like to run one if possible. The only problem is I can find about 14 different part numbers with no specifications on any of them. I have done a lot of reading on this subject and find many different ways to look at each turbo. Inducer size should be between 2.7”-3”. The exhaust housing should be 22cm or an a/r around 1.0.

I know I could and/or maybe should just go buy a set ready to go. This way I hope will be more fun once I figure out which turbos to run. Thanks for any help. PM me if you would rather.

 

Talk to Olee at Power By Poole. He builds his own twin turbo setups and would be able to give you the information you need. His website is www.powerbypoole.com

 

I would say use your 62 and look into a s400 for the primary.

 

Thanks for the replies. More information please. I just don't want to have to rebuild this set six months from now becasue I am not happy with their performance. Keep the info. coming please. Thanks again, Doug.

 

Starting point is to get an exhaust manifold from Power by Poole with a BOV on it. Then you will need a hot pipe from Power by Poole to accept the BOV input and the output of the 62's exhaust. If you have access to good welding and machining you can do it yourself. Look at Source Automotive for all the little bits you need. There is a nice s400 in the classifieds for 6 bills....good price for a new turbo. Start accumulating stuff and do some legwork. Help will come when you are less helpless. ks

 

start by finding a good spooling large turbo, stick it on the the engine to see how it fits, bolt it on and then you are done. Much simpler, more reliable and more HP. Its just that easy.