Has the DMax been dethroned ?

JoshH

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Feb 14, 2007
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Several times I've seen those things referred to as "compound" turbos. A couple other places including what looks like a Ford release "sequential", so that's what they must be. And a couple other places including an article, referred to them as "compound sequential." All the stupid bickering and so what?......who gives a damn what they're called. They're twin turbos.
They're also stock turbos. Saying you can't compare a stock turbo Duramax to a stock turbo 6.4 PowerStroke is ridiculous, and comparing a stock turbo 6.4 to an MPI equipped twin turbo Duramax is even more ridiculous.
 

Utahski

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Oct 20, 2008
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They're also stock turbos. Saying you can't compare a stock turbo Duramax to a stock turbo 6.4 PowerStroke is ridiculous, and comparing a stock turbo 6.4 to an MPI equipped twin turbo Duramax is even more ridiculous.


Fine. It's all stupid and none of it means crap. Think whatever you want and it's ok.
 

maine04max

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I read on another site last night a guy said he was getting 35psi boost from his stock . I know i cant get 35psi out of my ihi .so obviously they have an advantage there . more boost = more power how ever you look at it
 

malibu795

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Apr 28, 2007
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I read on another site last night a guy said he was getting 35psi boost from his stock . I know i cant get 35psi out of my ihi .so obviously they have an advantage there . more boost = more power how ever you look at it

your wrong my friend increase Boost does not equal increase HP.

increase air flow = increase hp

IMO cant judge a trucks HP by what boost it makes;)
 

whitetrash21

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Apr 29, 2008
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more boost means more restriction somewhere in the plumbing. Like Adam said, all comes down to how lbs of air/minute you can move.....
 

durallymax

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your wrong my friend increase Boost does not equal increase HP.

increase air flow = increase hp

IMO cant judge a trucks HP by what boost it makes;)

exactly. Our 470hp 60 series Detroit makes maybe 20-30psi under load. Heck it makes 15psi when engine braking.

At the same time ive watched the Kenworth at work with a 550 C15 Twin turbo CAT and a pittsburgh power box make 62psi with a light load.
 

durallymax

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more boost means more restriction somewhere in the plumbing. Like Adam said, all comes down to how lbs of air/minute you can move.....

And if theres more restriction theres probably more heat. The more heat there is in the intake charge the less dense it will be which means less ir can be packed into the cylinders therefore less fuel can be burned and less power is made.

Or im completely wrong.

What i dont get is that if Fords new turbo setup truely is sequential then why is it that way? IIRC it was Porsche that originally tried it many years ago and said it was very ineffiecient, expensive, bulky and an overall waste of engineering. But I guess thats what they do at Ford, that and forget to put two extra head bolts per cylinder.
 
Jun 28, 2007
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And if theres more restriction theres probably more heat. The more heat there is in the intake charge the less dense it will be which means less ir can be packed into the cylinders therefore less fuel can be burned and less power is made.

Or im completely wrong.

What i dont get is that if Fords new turbo setup truely is sequential then why is it that way? IIRC it was Porsche that originally tried it many years ago and said it was very ineffiecient, expensive, bulky and an overall waste of engineering. But I guess thats what they do at Ford, that and forget to put two extra head bolts per cylinder.

Is the ford sequential or compound? I thought it was compound:confused: Toyota Supras came through with sequential turbos.
 

malibu795

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Apr 28, 2007
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Haven't looked at Cat so I can't call them stupid but ford are a bunch of tards....the turbos are clearly compounded

cats acert twins look like 5.9 tiwns on steroids. with a JWAC (jacket water aftercooler) W-T-A intercooler befoer hte ATA intercooler... why because acordign to them discharge air temp from the primare is 500-600*:eek:

me thinks they are overspeeding the small charger :rolleyes: see if i can get pictures
this is cats C15 ACERT with sqeuntial twin turbos
DSCF0002.jpg
 
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TheBac

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And if theres more restriction theres probably more heat. The more heat there is in the intake charge the less dense it will be which means less ir can be packed into the cylinders therefore less fuel can be burned and less power is made.

Or im completely wrong.

What i dont get is that if Fords new turbo setup truely is sequential then why is it that way? IIRC it was Porsche that originally tried it many years ago and said it was very ineffiecient, expensive, bulky and an overall waste of engineering. But I guess thats what they do at Ford, that and forget to put two extra head bolts per cylinder.

Agreed on the "more heat, less power" thinking. Drag race on an 80* day, then race on a 60* day.....

I remember reading about VVT's on the old Chrysler 2.2/2.5 engines, and how they didnt work worth a hoot. Funny how with modern computer controls, an old idea can get new life....