Join DateFeb 2019LocationMichiganPosts5Thanks0Thanked 0 Times in 0 Posts
I did start a new thread under the Mechanical Upgrades Forum. Replying to Luckes_Duce, I htink my plan is going to be to run a fixed pressure off a regulated line that gets me a good spool with acceptable top end back pressure. If dumping the air and closing the VGT won't hurt the motor I'' going to put a air dump in to act as a Brake. I'm not a very experienced Diesel Turbo guy, other than crappy efficiency and over speeding the turbo can closing this thing down to ac as a brake hurt the motor (in any application)? This will take some experimenting but I think it will be cool
Join DateFeb 2019LocationMichiganPosts5Thanks0Thanked 0 Times in 0 Posts
I did start a new thread under the Mechanical Upgrades Forum. Replying to Luckes_Duce, I htink my plan is going to be to run a fixed pressure off a regulated line that gets me a good spool with acceptable top end back pressure. If dumping the air and closing the VGT won't hurt the motor I'' going to put a air dump in to act as a Brake. I'm not a very experienced Diesel Turbo guy, other than crappy efficiency and over speeding the turbo can closing this thing down to ac as a brake hurt the motor (in any application)? This will take some experimenting but I think it will be cool
I would check to see what the valve springs, mainly the exhaust springs are rated for. The 250 was never speced to have an exhaust brake. There is a lot of back pressure caused by closing the vanes, which creates the back pressure to slow down the motor. On the 5.9 cummins, you need to add heavier valve springs to handle that extra force. Also is the VGT actuator air or electric? the HE351 is electric, I dont remember seeing anything about air in the manual for the 551.
Just an FYI, if you leave a VGT is a fixed position, it should be all the way open. If its partially closed to help spool, you need to dynamically control it to help spool and create boost. That isnt something you can do with a hand valve. Plus if its half closed, you could run the risk of restricting the air supply enough to choke the motor and shut it off, especially in a high load situation when you get off the throttle quickly.
I would do more research on a VGT and how complex the controller is. Its not just a valve that opens and closes the vanes. Its a separate computer that controls all the functions....