Best mods for 12 valve Cummins towing and freeway speeds
 

Hello everybody newbie here I hope this is the right place to post this thread if not please correct me and point me in the right direction!! I have a 97 12 valve Cummins everything is pretty much stock I have done the AFC mods as in getting more rack travel And what not I have not fine tuned it yet!!i bought it with no fuel plate!! I already lost the gear housing cause the kdp!! At least that's over with!! I am looking to get around 400 HP I will be towing a big text trailer with mining equipment and also I pull fifth wheels that are usually gvwr 15000!! At 60mph I'm at 2200 rpm I would like to travel at 75 in a good rpm range and get best fuel mileage also what have you done with your intirior I hate mine!!! any pics appreciated thanks for the help I really appreciate it!!!

a 62/65 turbo is ideal for towing, you could go with a 62/68 which is the latest design. your gearing seems a bit weird. you may want to get 373 as it sounds like you may have the 410's. basically tuning and a turbo will get you to 400 horse. you can do sticks, and dv's and then tune it properly. first thing is get a plate back in it for tuning purposes. 0,10,100 are all good plates. i prefer a custom 0/100 ground by hand out of a stock plate and tuned accordingly. pulling that much weight you may consider egt control mods like a exhaust manifold and intake piping, don't waste money on a cold air intake. afe bhaf works best. get the dry type with a pre filter and you will be good to go. intake horn etc. crazy carl makes a nice 3.5 inch system. 3.5 intercooler pipes and a huge 3.5 horn. made 405 on a similar truck as yours with just a 4 gsk, 64.5/71 bd special turbo, crazy carls piping and a htt exhaust manifold. and tuning. thats not an ideal tow set up but you can make same power with the smaller turbo no problem.

So if you could dumb this down a little bit for me I am very interested in the same kind of deal for my 96 3/4 ton but I dont really understand whats being said. Your talking about changing gearing? whats egt, and afe? Sorry for my ignorance. :argh:

Twins and what you said?
 

what about a ht3b turbo under a hx35???? With some dvs and 4 gsk's and 60 ibs valve springs and 4?inch down pipe And exhaust!! Plus intake horn??? and then 3.73 gears what else??

The ht3b combo works but it's pretty out dated and more work/ heat/ loss of room then really necessary when you can just buy one turbo that is newer tech and does what you want in a simple package. With the ht3b tho yes you will achieve what you want. It will spool quick easily make 400 horse And support up to around 600-650. I personally would go with a better single now to make the 400 horse and compound later if you want more power. And Ya check your gear ratio. Seems a bit high for what you want.

And kruze.96 read the beginners thread. Then if you got questions start a thread or you can pm me

So the hx35 can't go over a hx35 If im thinking clear although couldn't that lower egts and help keep load off the one cause I have two hx35 but could you tell me where I'm not thinking right!!! Also what size of "single" turbo would you recommend for the weight I will be pulling!!! also I am goin thru front end steering like crazy even moog parts what would your recommendation be on that? And I found some 354 gears for my truck would that be to low or just add more hp and call it good??

The only way to run 2 hx35's is sequentially. Which is with a very expensive custom header running 1 turbo per 3 cyl. Not worth the hassle for a hx35. If I were you. I'd buy a bd killer b which is a 62 (61.5) turbo. Come with a full install kit and includes a 4" hx40 downpipe. There are other options but bd makes a nice simple set up. And will supply plenty of air. There are many many different options and ways of doing what you want but this is the most straight forward from a single reputable vendor. As for gearing it won't add any power. What you want for towing is for your rpm to be around 1800-2100 so you will need to do a ratio calculator and find out what gearing you need to make your truck run that rpm at the speed you want to cruise towing.

I also got no idea on front end parts on a dodge. I'm a Chevy guy. Moog is a good company. There are also lots of companys out there that I know make upgraded versions of the problemed dodge desgins but you'd have to look into it.

Please clarify your question, I'm not sure what you're saying is going on.