Cummins NTC 290 inframe build

You must remember that going to a larger turbo will make it have great top end power but getting the truck up to speed will be sad because the turbo will lag in getting spinning and making power till you get moving in top gears?

 

Depending on the turbo it could get worse.
I thank it was the HT3B turbo and pulse manifold that replaced the VT50 and log manifold. They did a good job on the SC's we up dated.

 

SmokinCAT probably forgot more about these than most people know. He just usually sits back, wise man. There are a couple other folks but they have not joined in.
The things that most people have suggested are right off what Cummins made from the factory. Who would know more about these engines than them?
About all we ever did with small cams was build them to the highest HP cpl without buying a cam. These trucks were normally gear bound because they were made when the national speed limit was 55. We usually used a bit lower number fuel button and set the no load RPM up at about 2500 RPM. Then they should pull out under load around 2350. That is to the best I remember. One built to a 400 and set up this way would surely get to 425 HP with no magic pixie dust.
I have learned that is not the best way but it worked OK for us. Folks drilling holes in dimes and such can cost you a lot of money.
If your turbo is good maybe just run it. The upgrade would be what came on a BCIII.
The 0160 was most common so why not go with that? Get a cooler set up from your salvage buddy.
We found transmissions to be a less expensive way to change gearing than diffs tires and wheels.

 

Yes, a HT3 is a holset, as far as the pulse manifold you have to watch which version you go after.

There are large and small port versions, you want to get the one that matches your heads, if you have the larger port heads that early pulse is hard to find and might be best to stick with the stock style log manifold.

 

You will never hurt a 12513 with the engine you have, I would not worry about the transmission.