Fitzgerald? Not sure what to do with aging truck

About 6 isn't bad out of a cat especially at that sort of miles and it's never been apart, I'd overhaul it to the same specs it's at now and have a pretty good idea what you have. If you're looking to replace it with a glider, just guessing from what you've given for information. You could get an n14 and they will get you about 7 or so tuned right. I have no idea what a Detroit really would get you for mileage, I wouldn't get one simply because you see 12.7s pushing 500 horse compared to a 14 or a little better, just seems too many potential problems to me.

 

If 500 horses out of a 12.7 is pushing it, then many guys are in deep doodoo.

 

It's probably fine, but to my hillbilly ### it seems sketchy to try getting the same horse out of a smaller motor.

 

Agree. 15.2 is 928 cubic in engine. 12.7 is 775 cu.in. Quite a difference. Not sure where the hp limit or torque limts are but they are both great engines. 5.8 to 6 mpg is my fair average for my c-15. Winter less. Have pitts power box , smooth flow exhaust manifold, and larger turbo. No waste gate. But I run it easy. Not how fast I pull the hill, its how many times. ( without breakdowns =$$).

 

You probably already know..but want to say, if you do decide to let truck go. Don't let that engine go for cheap. They are in demand. Read somewhere that the "good" engine blocks are getting hard to find.

 

Many of the 12.7L Detroits were factory 500hp. Not pushing anything there.

 

Yea and they last as long as a c15 doing it too it seems, like I said I don't know much about them.

 

That's good ol' GM engineering at work there.

 

If my memory serves right, that engine was originally designed by John Deere. Then GM acquired it and fine tuned it with the help of some of Penske's money.