SD25 turbodiesel
Posted: Sun Oct 20, 2013 8:18 pm
I met a guy threw craigslist, he bought an exhaust manifold from me for a SD series engine, he planned on cutting a hole in the side of it to make a turbo mount, we discussed the idea and I suggested that instead of doing it that way, that since he had the room, he should make a head pipe that curved up from the stock exhaust exit, and mount the turbo just above the alternator.
I have been getting updates since that day, and the other day I received a message claiming success, so I went over Saturday to take a look, and this is what I seen, this photo supplied by Larry.
All the turbo conversions have failed that I know about, but this guy did it different, this is his parts list, KO3 turbocharger by KKK,
and 34mm blow off valve(BOV) that is controlled by vacuum,
the pyro is located near the stock manifold exit,
this is the "T" that controls the BOV,
This is the choke cable that is connected to the injection pump control arm controls two things, it shuts the engine down, and it sort of leans the engine out if you pull it only part way,
and this is my photo of the engine compartment.
OK, so how Larry did it is he mounted the turbo beside the exhaust manifold sorta high, so he had to cut a hole in the hood, he did it on purpose, he wants to cool the turbocharger with air as well as water, he plans on a reversed hood scoop that pulls air threw,
the exhaust goes strait to the turbo, then goes to the rear via a 3 inch exhaust pipe without a muffler all the way to the rear bumper, and it is quiet when running, I was surprised, he then piped it from the stock air filter to the turbo inlet, all the piping was bought on Ebay, from there it goes to the BOV, then to the stock throttle body, this BOV is controlled by the vacuum created in the stock throttle body injection pump control line, you see the injection pump is controlled by vacuum on these US imported diesel engines, there is a small venturi in the throttle body that when you let off the pedal, it creates vacuum and that vacuum pulls the injection pump back to the idle position, if you give it a little pedal, it gives it a little more fuel, if you floor it, the throttle body venturi loses all vacuum, so the injection pump is floored, so he put a "T" in this vacuum line that goes to the BOV, when you let off the pedal, it creates vacuum, and the BOV lets all the pressure out of the system after the turbo, and before the throttle body, give it some pedal, and the BOV closes and starts giving it boost again, the throttle body is left stock, so when one lets off the pedal, there is enough vacuum created to overcome the boost in back of the venturi, there are two lines that are connected to the pump, one controls the injection pump, the other is vented to the air, and the last thing he did was put that cable on the injection pump control arm to control the power, pull the cable a little and it restricts the fuel(less fuel, less power), pull it all the way and it cuts the fuel off all the way.
The turbo has been messed with, he put different fins in the exhaust side to give it more boost, and I believe that he messed around with the smoke screw.
This is the most thought out approach to this I have seen/read so far, he plans on connecting the pyro to a gauge, and he plans on piping water threw the turbo also, he has not connected a boost gauge yet, and had not decided where to connect it yet when I was there, the oil for the turbo was taken from the vacuum pump oil source, and it was piped back to the block without any bends in the line via the vacuum pump return line, the water is going to come from the heater core return line as far as I know.
I heard this engine run, it revs faster than my engine, so far this looks to be the only successful SD series turbodiesel I have seen or read about, he told me of no issues, but he did not know how hot it was running, nor did he know how much boost he had, as the gauges had just came in the day before, he also is going to use an inter-cooler, but did not want to spend the money for that before he knew it was going to work, I eagerly await updates from him, as I want to do this myself, but anything I would have done to date, would have been a backyard hillbilly version, Larry seems to be very smart and resourceful, and if I actually ever do get a turbodiesel set up and running properly, he will be the reason it works properly.
I have been getting updates since that day, and the other day I received a message claiming success, so I went over Saturday to take a look, and this is what I seen, this photo supplied by Larry.
All the turbo conversions have failed that I know about, but this guy did it different, this is his parts list, KO3 turbocharger by KKK,
and 34mm blow off valve(BOV) that is controlled by vacuum,
the pyro is located near the stock manifold exit,
this is the "T" that controls the BOV,
This is the choke cable that is connected to the injection pump control arm controls two things, it shuts the engine down, and it sort of leans the engine out if you pull it only part way,
and this is my photo of the engine compartment.
OK, so how Larry did it is he mounted the turbo beside the exhaust manifold sorta high, so he had to cut a hole in the hood, he did it on purpose, he wants to cool the turbocharger with air as well as water, he plans on a reversed hood scoop that pulls air threw,
the exhaust goes strait to the turbo, then goes to the rear via a 3 inch exhaust pipe without a muffler all the way to the rear bumper, and it is quiet when running, I was surprised, he then piped it from the stock air filter to the turbo inlet, all the piping was bought on Ebay, from there it goes to the BOV, then to the stock throttle body, this BOV is controlled by the vacuum created in the stock throttle body injection pump control line, you see the injection pump is controlled by vacuum on these US imported diesel engines, there is a small venturi in the throttle body that when you let off the pedal, it creates vacuum and that vacuum pulls the injection pump back to the idle position, if you give it a little pedal, it gives it a little more fuel, if you floor it, the throttle body venturi loses all vacuum, so the injection pump is floored, so he put a "T" in this vacuum line that goes to the BOV, when you let off the pedal, it creates vacuum, and the BOV lets all the pressure out of the system after the turbo, and before the throttle body, give it some pedal, and the BOV closes and starts giving it boost again, the throttle body is left stock, so when one lets off the pedal, there is enough vacuum created to overcome the boost in back of the venturi, there are two lines that are connected to the pump, one controls the injection pump, the other is vented to the air, and the last thing he did was put that cable on the injection pump control arm to control the power, pull the cable a little and it restricts the fuel(less fuel, less power), pull it all the way and it cuts the fuel off all the way.
The turbo has been messed with, he put different fins in the exhaust side to give it more boost, and I believe that he messed around with the smoke screw.
This is the most thought out approach to this I have seen/read so far, he plans on connecting the pyro to a gauge, and he plans on piping water threw the turbo also, he has not connected a boost gauge yet, and had not decided where to connect it yet when I was there, the oil for the turbo was taken from the vacuum pump oil source, and it was piped back to the block without any bends in the line via the vacuum pump return line, the water is going to come from the heater core return line as far as I know.
I heard this engine run, it revs faster than my engine, so far this looks to be the only successful SD series turbodiesel I have seen or read about, he told me of no issues, but he did not know how hot it was running, nor did he know how much boost he had, as the gauges had just came in the day before, he also is going to use an inter-cooler, but did not want to spend the money for that before he knew it was going to work, I eagerly await updates from him, as I want to do this myself, but anything I would have done to date, would have been a backyard hillbilly version, Larry seems to be very smart and resourceful, and if I actually ever do get a turbodiesel set up and running properly, he will be the reason it works properly.