Compound turbochargers

[EatonEggbeater]

Was looking at an industrial generator and saw that this setup had 2 turbochargers inline with each other.

Some of you guys have experience with these things, was curious what the upside to this configuration is.

Other than that, I just thought it was pretty cool.

 

[Coiled03]

Happens a lot on heavy duty industrial engines. Usually, it's a low pressure turbo feeding a high pressure turbo.

Sometimes it's done for packaging, sometimes it's for efficiency, or one of several other reasons.

 

[03cobra#694]

One of my old trucks had a twin set up like. It was a 475HP Cummins.

 

[AustinSN]

Happens a lot on heavy duty industrial engines. Usually, it's a low pressure turbo feeding a high pressure turbo.

Sometimes it's done for packaging, sometimes it's for efficiency, or one of several other reasons.

Pretty much this.

Performance diesel engines, if they have more than 1 turbo, are almost always compound setups. You can run some serious pressure through them and they spool better than a big single.

This isn't me, I found it on google. You can see the compound setup on the Scheid dragster.

 

[AustinSN]

Oh and the 6.4 Powerstrokes are compound setups, but they are a little weird. IIRC, the 6.4s have a small turbo feeding a large turbo, when traditionally it's the other way around.

 

[SID297]

Have them on my 6.4. The theory is the small one spools really fast so you don't get a lot of turbo lag. Then the big one lights off and you make big steam.

 

[SonicDTR]

Yep, 6.4 powerstroke has them. Big one is called "atmospheric" and the little one "high-pressure". Theory is just like Sid said.

Spool is crazy on mine, like 1-2psi at idle haha. I can brake boost 20+ psi at 1500rpm really easily.

 

[MTBSully]

What they said.

 

[Kiohtee]

This thread delivers. Good info fellas.

 

[PACIFICGREENSVT]

Saw this the other day, check it out.
https://www.carthrottle.com/post/vo...nology-uses-compressed-air-to-kill-turbo-lag/

 

[SonicDTR]

Saw this the other day, check it out.
https://www.carthrottle.com/post/vo...nology-uses-compressed-air-to-kill-turbo-lag/

Pretty neat, i've had that idea for years, and its been messed with in various forms by companies over the last decade.

 

[SonicDTR]

Shameless plug, you can watch my gauges on this run in my truck. Running factory style sequential compounds.

Fresh air comes in the filter, thru big turbo and into little turbo, then intercooler, intake, and heads.

Exhaust comes from manifolds, to up pipes, to little turbo, then to big turbo, and out the downpipe.

[youtube_browser]7sBI0aAsgOM[/youtube_browser]

 

[GotHemi?]

Learned something new!

 

[hockeylover86]

Super stock diesels usually run triples (2 into 1) in the pulling classes.

Do a search for Haisley's and Scheids trucks, some good pics.

 

[AustinSN]

Super stock diesels usually run triples (2 into 1) in the pulling classes.

Do a search for Haisley's and Scheids trucks, some good pics.

If you go to diesel events, every once in a while you'll come across a guy with a 24v cummins who can run a bead and had a few extra turbos laying around lol.

Same idea, but 3 turbos feeding 1 lol.

 

[Sn95Snake]

Have them on my 6.4. The theory is the small one spools really fast so you don't get a lot of turbo lag. Then the big one lights off and you make big steam.

I have heard of this but have never actually seen pictures of it until now.

 

[rotor_powerd]

Oh and the 6.4 Powerstrokes are compound setups, but they are a little weird. IIRC, the 6.4s have a small turbo feeding a large turbo, when traditionally it's the other way around.

No the larger turbo feeds the smaller one. That's the only way that compounds work. Turbos are pressure multipliers so you can cram a bunch of air into a smaller turbo and it will still compress it to whatever ratio it is set to run at.

 

[BlksvtCobra01]

Neat learned something new.