Reb. B said:
Yes. Like i said, mine is at 703 with no NOS and it has a goose neck hitch and pulls cattle trailers around daily. Its even got one on John's pumps on in now and can really pull now. BUT, and this is a big BUT, ... the ability to run a big turbo is done much easier with a common rail. I've tried putting my turbo on several 12v's and its just sits there and smokes and turbo barks all day long. And thats why i like the common rail because of the abilty to spool turbos, because whoever can run the bigger turbo on the street is going to win(racing around town). Several reason why I'm not fond of twins are: its too hard to regulate boost both top end boost and middle range boost, especially when towing, ... . its less reliable, meanning that hoses are wanting to blow, intercoolers are wanting to blow and gaskets are wanting to blow. Now, back to regulating boost when towing. Say you have a fifth wheel camper and you are going up a long hill,. . with twins its very, very hard to keep the boost under 40 psi. Okay, your EGT's may be low, but what isn't, is your boost. As boost rises so does the temperature of your charged air. At 20 psi the air going through the intercooler is 210 degrees. At 40 psi boost the air is 420 degrees. Okay, so 420 degrees going through your intercooler is being radiated in front of your radiator, becuase the intercooler sits directly in front of your radiator. So driving up a hill with 20 to 40 psi boost is like driving in the midlle of Death Valley when its 210 to 420 degrees outside. Your engine water is going to get hot. SOOO, with a set of twins, EGT's are not the problem but engine water cooling is. What i have found on the common rail is that with a large single, ... if you can keep the rail pressures high enough, and get a complete burn the egt's will be in check. With Don's 40 inj and the TST on level five and 703 HP, the eng would never seeover 1250 degeres at WOT. Now with Don's 100 inj. this is a different story. Keeping rail pressure up is a little harder now.
Moral of the story is this, I'm not putting down owners that have bought twins, but I'm informing people in the market for twins. They cost a fortune, they make the head gasket and everything air related less reliable, and when the problems start happening this really discourages the owner. And my thought is that the owner should be happy with his truck. Thats all. These are my thoughts, take it for what its worth. There are lots of ways to make power. On the common rail, i spent my money on fuel and air, and not on the long block. This is what Joe D. did and he was very succesful.