Twins, Twins, Twins, Twins, Twins............
The nicest looking Cummins twins are likely the MPI twins out of Idaho.
Traditional layout with all the piping down low & no air filter heat shield. They are not the cheapest though..


Here is an interesting thread on MPI twins & some guys' turbo history & their continual turbo upgrades...
https://www.dieseltruckresource.com/...2-t186665.html
Traditional layout with all the piping down low & no air filter heat shield. They are not the cheapest though..


Here is an interesting thread on MPI twins & some guys' turbo history & their continual turbo upgrades...
https://www.dieseltruckresource.com/...2-t186665.html
Don't forget about the external gate, its make the difference. Everything before an external gate is old school. Today you can have your cake and icing, with some ice cream. The GT3582R will out spool any similar sized turbo. I was really impressed with the performance of the GT4202 and it spools decently for a big turbo. That GT4202 wastegate 1.01 T-6, I had one, but the one I'm using today is a T-4, 1.28. The T-4 GT4202 seems performs better on a mild truck. We must have tried three to four different housings on that turbo.
Talking to Steed today, I'm the only guy that has ever ordered a steed manifold with a T-3 flange and 50mm external gate flange.
Talking to Steed today, I'm the only guy that has ever ordered a steed manifold with a T-3 flange and 50mm external gate flange.
Don't forget about the external gate, its make the difference. Everything before an external gate is old school. Today you can have your cake and icing, with some ice cream. The GT3582R will out spool any similar sized turbo. I was really impressed with the performance of the GT4202 and it spools decently for a big turbo. That GT4202 wastegate 1.01 T-6, I had one, but the one I'm using today is a T-4, 1.01. The T-4 GT4202 seems performs better on a mild truck. We must have tried three to four different housings on that turbo.
Talking to Steed today, I'm the only guy that has ever ordered a steed manifold with a T-3 flange and 50mm external gate flange.
Talking to Steed today, I'm the only guy that has ever ordered a steed manifold with a T-3 flange and 50mm external gate flange.

Don't forget about the external gate, its make the difference. Everything before an external gate is old school. Today you can have your cake and icing, with some ice cream. The GT3582R will out spool any similar sized turbo. I was really impressed with the performance of the GT4202 and it spools decently for a big turbo. That GT4202 wastegate 1.01 T-6, I had one, but the one I'm using today is a T-4, 1.01. The T-4 GT4202 seems performs better on a mild truck. We must have tried three to four different housings on that turbo.
Talking to Steed today, I'm the only guy that has ever ordered a steed manifold with a T-3 flange and 50mm external gate flange.
Talking to Steed today, I'm the only guy that has ever ordered a steed manifold with a T-3 flange and 50mm external gate flange.

I stumbled upon this DTR thread while searching "external wastegate". It has certainly been informative reading!
Here is an interesting thread on MPI twins & some guys' turbo history & their continual turbo upgrades...
https://www.dieseltruckresource.com/...2-t186665.html
Hey that thread looks familiar!
Here's an update to it:
http://www.competitiondiesel.com/for...d.php?t=109883
I need more supply fuel. Then I'll re-dyno.
Based on those results I'll decide if I want to go BB secondary with external wastegate.
Here is an interesting thread on MPI twins & some guys' turbo history & their continual turbo upgrades...
https://www.dieseltruckresource.com/...2-t186665.html
Here's an update to it:
http://www.competitiondiesel.com/for...d.php?t=109883
I need more supply fuel. Then I'll re-dyno.
Based on those results I'll decide if I want to go BB secondary with external wastegate.
That thread primary is litely loaded, at only 29psi, the primary is just starting to work. That the big benieft to the external gate. You just adjust the in-cab controller, you can reduce the amount of work the top turbo is doing and get the primary to work harder. Hard to have the flexiblity with an internal gate.
That GTX turbine wheel looks difference than mine. Mine has more of scoop to the blade. There is no question, if you can afford it, go with the garrett BB.
We also have a set of twins going together with a lot bigger impellers. 66mm for the secondary and 104mm for the primary.
That GTX turbine wheel looks difference than mine. Mine has more of scoop to the blade. There is no question, if you can afford it, go with the garrett BB.
We also have a set of twins going together with a lot bigger impellers. 66mm for the secondary and 104mm for the primary.
The nicest looking Cummins twins are likely the MPI twins out of Idaho.
Traditional layout with all the piping down low & no air filter heat shield. They are not the cheapest though..

Attachment 36062
Here is an interesting thread on MPI twins & some guys' turbo history & their continual turbo upgrades...
https://www.dieseltruckresource.com/...2-t186665.html
Traditional layout with all the piping down low & no air filter heat shield. They are not the cheapest though..

Attachment 36062
Here is an interesting thread on MPI twins & some guys' turbo history & their continual turbo upgrades...
https://www.dieseltruckresource.com/...2-t186665.html
This is the color of powdercoat I would like to go with Mike. Pretty excited to get it all on bro!!!
Thats a grey/black speckled or white/black speckled. I'll check and see if I can get that color for ya. You want the compressor housing the same color? Or just go with the stock finish? Should turnout to be a pretty awesome performing set-up with abit of underhood bling.
Thats a grey/black speckled or white/black speckled. I'll check and see if I can get that color for ya. You want the compressor housing the same color? Or just go with the stock finish? Should turnout to be a pretty awesome performing set-up with abit of underhood bling.
Sounds like your twins upgrade project is coming together Jamie, good to hear!
As for powder coating/ceramic coating, while it will slow down the entire install, it is well worth it.
Mock everything up, temporarily bolt everything up, fix any issues or whatever.. Take it all apart, even dismantle the turbos to get them coated & send it all over the coater.
Then the impatient waiting starts.. I had to wait 2.5 weeks just to get my exhaust elbow & downpipe ceramic coated here in Calgary.. The wait drove me nuts but it was worth it.
As for powder coating/ceramic coating, while it will slow down the entire install, it is well worth it.
Mock everything up, temporarily bolt everything up, fix any issues or whatever.. Take it all apart, even dismantle the turbos to get them coated & send it all over the coater.
Then the impatient waiting starts.. I had to wait 2.5 weeks just to get my exhaust elbow & downpipe ceramic coated here in Calgary.. The wait drove me nuts but it was worth it.
Have everything figured out. Just waiting on the steed stuff to show up. You probably went to top gun for coating. Found quicker turn around time elsewhere. Been short of driving to Kelowna, driving me crazy. My spec is different than the typical for a steed manifold. I'll call tomorrow and raise some stinky.



