Compound Turbos

"Yowen - not necessarily not spaghetti and meatballs" (yowen)
10/29/2013 at 11:30 • Filed to: None

I hope this guy paints his engine, because the rest of it looks amazing.
(1967 Ford F100 with 4BT swap, build thread !!!error: Indecipherable SUB-paragraph formatting!!! ).

DISCUSSION (20)

jlmounce > Yowen - not necessarily not spaghetti and meatballs
10/29/2013 at 11:46

Does look fairly awesome and I'm sure it's probably just in mockup stage. Pretty badass! I took a look at the build thread and there's a lot of nice fabrication going on there.

Casper > Yowen - not necessarily not spaghetti and meatballs
10/29/2013 at 11:48

Oh my god. This is the next swap I was looking at doing as my toy for pulling my cars around. I was going to go with twinscroll turbo setups, but I'm very interested to see how he did it.

Thanks for the link.

Yowen - not necessarily not spaghetti and meatballs > jlmounce
10/29/2013 at 11:51

Yes indeed there is.

Yowen - not necessarily not spaghetti and meatballs > Casper
10/29/2013 at 11:53

No problem! There is another guy in there with a Tahoe that switches to compound toward the end of his build thread:

http://www.4btswaps.com/forum/showthre…

HammerheadFistpunch > Yowen - not necessarily not spaghetti and meatballs
10/29/2013 at 12:09

Having been in a converted 4BT cruiser; No thanks. The worst motor ever. Not that it can't be powerful and reliable, but it was literally worse than being in a tractor.

Yowen - not necessarily not spaghetti and meatballs > HammerheadFistpunch
10/29/2013 at 12:17

I hear it is rough and noisy. I imagine some builds are better than others and some vehicles lend themselves to this type of motor better than others.

Due to the torque and only having 4 cylinders I hear these are hell on transmissions. I hear the 6bt runs much smoother because it fires 50% more often.

HammerheadFistpunch > Yowen - not necessarily not spaghetti and meatballs
10/29/2013 at 12:20

The 4BT is junk, its only good for industrial/commercial use. Sure it gets decent economy, and is well built but its not remotely suited for passenger car use.

Kugelblitz > Yowen - not necessarily not spaghetti and meatballs
10/29/2013 at 12:21

Compound Turbo's what?

Or do you mean plural as in Compound Turbos? I would pull some hair out but I used it all up already.

Grammar, I have it. Help me.

Yowen - not necessarily not spaghetti and meatballs > Kugelblitz
10/29/2013 at 12:23

Compound Turbocharger System... Is that satisfactory?

Kugelblitz > Yowen - not necessarily not spaghetti and meatballs
10/29/2013 at 12:33

Nice save. Yes.

LandSpeed-DSM > Casper
10/29/2013 at 13:47

You can still use a twin-scroll unit effectively as the Secondary/High-pressure stage in a compound setup. Or one twin scroll unit per bank as the HP stage feeding a very large single as the Primary/Low-pressure or atmosphere turbo, though they (HP units) won't be receiving pulses at equal intervals unless you route them cross-bank.

Casper > LandSpeed-DSM
10/29/2013 at 13:50

That's what I was planning to do. I was going to do a custom manifold to match the stagger needed for the twinscroll, then feed the output to the larger unit... or just run a single really high end turbo like a twinscroll EFR and deal with hurdles as they come up. They can achieve the boost needed with a much lower requirement to establish spool. Just not sure how their integral components work on diesel applications.

LandSpeed-DSM > Casper
10/29/2013 at 13:55

Is this an inline 6? (ex. 6BT Cummins) With a V arrangement 8 cylinder your best bet is to just use one scroll per bank if going the divided route. What displacement/rpm do you have at your disposal? Goals for whp/wtq or where in the rev range you want to make the power?

The EFR series only goes up to the 9180 at the moment, which on the turbine side is just about too small for really any diesel or gas V8 sold stateside.

Casper > LandSpeed-DSM
10/29/2013 at 13:57

It's a 4BT so inline 4.

LandSpeed-DSM > Casper
10/29/2013 at 14:00

Gotcha, yea that won't be so bad to fab up.

Casper > LandSpeed-DSM
10/29/2013 at 14:01

There should be plenty of room to play with. I would like to move the turbo forward in the bay when I'm designing it and blanket the turbo as well as wrapping pipe to keep heat under control. If I do the build, it will be a pretty hotrod build and will have heat issues, so I'll plan for them from the start.

LandSpeed-DSM > Casper
10/29/2013 at 14:11

If you can, plumbing/mounting the LP stage to face forward and receive clean air helps a lot. I pick up a 2-3psi boost from my ram intake on a 2nd-3rd gear pull on the highway vs. on the dyno with the same waste-gate springs installed.

Drive pressure ratio drops, IATs drop, airflow goes up and it makes more power per psi boost.

This effect would be magnified in a staged compressor setup.

Casper > LandSpeed-DSM
10/29/2013 at 14:17

One idea I have toyed with after building my Z was segmenting the engine bay. Building an aluminum deflector and ducting air through radiator/IC, into the front of the bay, and diverting it up and through hood vents to exit the hood 3/4 of the way to the windshield. I could then expose the turbos onto the fresh air side of the shield for extra cooling/heat isolation. All depends on the overall design and ambition.

LandSpeed-DSM > Casper
10/29/2013 at 14:24

Make sure to share when its coming together. Good luck!

Casper > LandSpeed-DSM
10/29/2013 at 14:25

Still gotta get the Z finished up. It's just about together to do more testing, then I can do more power upgrades, and then (hopefully) it will be dialed properly and I can move on to a new project.

When the Z is done I'll do a full write up post on here too.