I know this is an old thread, but I was bored so I was surfing Service and Maintenance.
I've been driving a 1st generation Cummins for 16 years now. First generation motors are not intercooled. The Bosch VE pump in my truck is mildly tuned, running 4" exhaust, and a bit more boost than stock. I can't give you many specifics, because my son specified it and put it together.
Anyway, about a month ago, I was doing some hauling in the mountains of WV, just south of Morgantown. Land of the 5-mile, 5% grades. Near the top of one of those grades, she overheated, because she had blown out all the coolant. [That's another story.] Melted a piston. #5 or #6, I can't quite tell. #5 is more susceptible, because it's not on the end of the block. Still runs OK, but has a helluva piston slap until the engine warms up. Pushing some oil out the breather. Tailgate being automatically conserved while I drive. So, motor is due for replacement,...soon (anybody have a junkyard short block to sell me?). But, still, I've put 1000 miles on it, since that incident!
Bottom line: air gets hot when you compress it, and when you pour more fuel and boost into the mix, you're creating a situation not unlike one of those old hand-cranked coal forges. The faster you spin the handle, the hotter it gets.
The smaller Kubota 3-cylinders already have a reputation for struggling to keep up with the heat the naturally aspirated motor generates! And, remember, the 1st gen Cummins was DESIGNED for turbocharging! The engineers detuned the nuts out of theses engines to control warranty claims. Bone stock, they're rated at only 160hp, but 1000hp (at the rear wheels, on a dyno) is well within reach without any work to the bottom end. Just because you can doesn't make it a Good Idea, despite the 'gee whiz' factor.
By the way, many years ago, my son did the same thing with his 900hp 1st gen, boosted to 60 lbs, on a 1 mile, 3% grade. That's when he added an intercooler and an exhaust temp gauge.
Live and learn,
-Paul
I've been driving a 1st generation Cummins for 16 years now. First generation motors are not intercooled. The Bosch VE pump in my truck is mildly tuned, running 4" exhaust, and a bit more boost than stock. I can't give you many specifics, because my son specified it and put it together.
Anyway, about a month ago, I was doing some hauling in the mountains of WV, just south of Morgantown. Land of the 5-mile, 5% grades. Near the top of one of those grades, she overheated, because she had blown out all the coolant. [That's another story.] Melted a piston. #5 or #6, I can't quite tell. #5 is more susceptible, because it's not on the end of the block. Still runs OK, but has a helluva piston slap until the engine warms up. Pushing some oil out the breather. Tailgate being automatically conserved while I drive. So, motor is due for replacement,...soon (anybody have a junkyard short block to sell me?). But, still, I've put 1000 miles on it, since that incident!
Bottom line: air gets hot when you compress it, and when you pour more fuel and boost into the mix, you're creating a situation not unlike one of those old hand-cranked coal forges. The faster you spin the handle, the hotter it gets.
The smaller Kubota 3-cylinders already have a reputation for struggling to keep up with the heat the naturally aspirated motor generates! And, remember, the 1st gen Cummins was DESIGNED for turbocharging! The engineers detuned the nuts out of theses engines to control warranty claims. Bone stock, they're rated at only 160hp, but 1000hp (at the rear wheels, on a dyno) is well within reach without any work to the bottom end. Just because you can doesn't make it a Good Idea, despite the 'gee whiz' factor.
By the way, many years ago, my son did the same thing with his 900hp 1st gen, boosted to 60 lbs, on a 1 mile, 3% grade. That's when he added an intercooler and an exhaust temp gauge.
Live and learn,
-Paul
