3406B power

I had one and it was rebuilt to haul, just working the rack will not do much except burn fuel and if your injectors are not working properly they turn into cutting torches and burn into the pistons.

A tune up is better than a turn up on a 3406B

 

That was "the" motor for many years "Four and a quarter Cat" 425 hp. Doesn't seem like much now, but when Internationals were putting out mostly 350's and this was before Cummins N14 it was pretty hot. not to mention solid and reliable. I'm not sure about perfomance options, but if it's running well I'd leave it alone and take what it gives you.

 

You know just reading your post took me back in time for a moment to a day when a big cam 400 cummins, a four and a quarter cat, and alot of other engines just like those was the king of the roads but my generation wouldn't really know about that much today unless they grew up around the seventies and the eighties and around those kinda manual pump engines and trucks. It is true that there was alot more mechanical failures and blow ups with those kind of engines but alot of it was just from stupidity. People always trying to make them hotter than stock and f ing them up and not really knowing how to do it just playing around with everything.

It takes someone who really knows what there doing with one of those engines to make it do somthing and live. That was the good ole days and those days are really gone for ever as far as the trucking industry goes but im glad to see that a few independents out there are still keeping those dinasoaurs alive. That was the kinda trucks and engines that molded me into who I am and made me want to learn about trucks and engines as I got older. Of course now its all electronic and you got to be able to work on them now or at least know someone who can work on them if there is a problem and beleive me for the last 7 or 8 years they have had alot of problems with things especially and the most on the EPA and emmissions side. Thanks for the post because sometimes I just like to zone out forget these electronic disasters and go back in time to a better day.

 

I have no clue what your definition of heavy is, but it can be done it its done the right way... If you take care of the motor it will last as long as these newer ones or atleast close to it.

 

You can get 600 HP out of a B cat motor, no wires or computer. Just saying