i've read lots about turning up the power on diesels, i feel like maybe i will go down that path.
i have a '93 cummins 5.9 spec'd at 190hp. after 25 years of running, 320,000 miles, im not sure if turning it would break it or help it.
according to the interweb the first gen motors arent capable of huge horsepower but they can be tweaked up. the pump limits them to a max of about 500hp.
then there is that pesky AT545, that runs out of clutch around 250hp.
i don't think that i'd change the governor, i dont want to see my motor running any higher than the 2500rpms or so its governed at. so no extra speed.
i tow frequently, and in the mountains with the bus. i'd like to give it a bit of umphf, and maintain my speed better climbing hills.
by that article or many others, i can change, or rotate the fuel pin, in the Air Fuel Control (AFC) and add about 40hp. if my truck still puts out 190, then i'd push up to 230hp, or the limit of the transmission.
i can rotate the stock pin for free, or buy a performance pin for about $100. it looks like a pretty simple modification.
the only other forum member i recall saying they turned up the screw was guy named Lapeer, he wholeheartedly encouraged it.
on the down side, i have asked 2 different diesel shops to do it for me and they both declined. saying it was illegal and shortens the motors life.
i recently added an oil cooler and that helped out the power of the truck. that kind of gave me a taste for more power.
at 320,000 miles with a strong running engine, not sure if i should let it be or try and squeeze some life out of her. the reading of diesel forums i've seen attitudes that the engine doesnt care if its 30k miles or 300k miles when you turn it up. that the power is there.