Effects of undivided ext. gate spacer on divided manifold & turbine housing

PASSENGER said:
I've bolted on tubular manifolds and without tuning seen a drop of 200* and have lost zero response or spool up.
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I sited an example showing exactly the opposite. And just to make it clear no one needs a data logger to be able to observe boost response from 0 to 10 psi I assure you i'm not making the results I noticed up. Now, that being said what would be your explanation for the difference? Also, the exhaust manifold had less volume than the header.
 
How bout this. Passenger donates a header to me and I run down to the local dyno and compare it and my ported stocker. Sound good? LOL
 
Joesixpack said:
I just want to see that water cooled manifold.

And why not cool the gas. Heat isn't important right?
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Same reason you don't put a torch on your manifold to increase the temperature of the gas. No reasonable performance gain.

I'll keep looking for the watercooled manifolds. They were a couple 4bts on a tri cabin troller (marine app).

NickTF said:
I sited an example showing exactly the opposite. And just to make it clear no one needs a data logger to be able to observe boost response from 0 to 10 psi I assure you i'm not making the results I noticed up. Now, that being said what would be your explanation for the difference? Also, the exhaust manifold had less volume than the header.
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I'd have to see the header, but if it is at all like most headers out there the design is likely a lot less than optimal.

BgBlDodge said:
How bout this. Passenger donates a header to me and I run down to the local dyno and compare it and my ported stocker. Sound good? LOL
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Lol. I am working on the 6.7 intake horn right now, check out the fab forum for updates on that. After that I am looking to pursue charge air coolers, than back to exhaust manifolds.
 
Joesixpack said:
I just want to see that water cooled manifold.

And why not cool the gas. Heat isn't important right?
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I was just thinking about your comments a bit more. I think maybe you aren't grasping what I am saying, which is, heat, in itself, does not, drive the turbine. It is merely a by product.
I have a little 2L honda engine I put together and built a turbo system for sitting here. The turbo is a hx52 hotside with an hx55 cold side. At a mere 4000rpm and only 1150* egt I am making 15psi on the cold side.

Think about it, its 1/3 the displacement of one of these cummins, and the egts are anything but hot. So whats driving it? Gas velocity, thanks to good ports and a good tubular manifold.
 
what increases velocity? pressure... what increases pressure? HEAT

water cooled manifolds and turbine housings are used for marine applications to reduce engine room/bay temps to prevent fires... marine applications are constant load and higher RPM, they're not concerned with low RPM spool up
 
I like this style manifold:
36c20580.jpg

A header Style:
HPIM0580.JPG


Oh, I applaud all types of these. I only wish I hd, the know how, the skills, and the tools to creat something of this type, including the header Passenger makes.
 
Forrest Nearing said:
what increases velocity? pressure... what increases pressure? HEAT

water cooled manifolds and turbine housings are used for marine applications to reduce engine room/bay temps to prevent fires... marine applications are constant load and higher RPM, they're not concerned with low RPM spool up
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Yes, heat can increase pressure. However this is not what happens in an exhaust manifold. Pressure is increased in an exhaust manifold and turbine because they are of a fixed volume, that fixed volume is being filled with an unfixed amount of exhaust gas, as engine speed increases, along with air and fuel, the pressure rises, as the exhaust gas is not leaving the turbine as quickly as it is entering it.

The whole watercooled manifold thing was really just a joke to the poster "turbo performance". Having built them I am well aware of the purpose of a watercooled manifold.
 
guys guys guys, are we going to have to pull out the thermodynamics book and reference the example problems of energy differential across a turbine?


bottom line, we are all out to get the maximum change in energy across the turbine section! who else has been drinking?
 
Forrest Nearing said:
what increases velocity? pressure... what increases pressure? HEAT

water cooled manifolds and turbine housings are used for marine applications to reduce engine room/bay temps to prevent fires... marine applications are constant load and higher RPM, they're not concerned with low RPM spool up
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Almost my thoughts exactly. Although earlier Passenger and I seemed to be debating the benefits/drawbacks of two completely different types of heat. One type caused by ****ty manifold design/flow and the other being heat from cylinder burn.

If you're making the heat, you might as well control it and use it, even if it's useless in some people's eyes. :rolleyes:
 
the heat is in the engine's exhaust gas... that wasn't a serious question, right? :confused:

the argument is letting it radiate through the header primaries vs. being focused on the turbine
 
Forrest Nearing said:
the heat is in the engine's exhaust gas... that wasn't a serious question, right? :confused:

the argument is letting it radiate through the header primaries vs. being focused on the turbine
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Yes obviously the exhaust gas is hot, I was asking you why or what is causing it to be hot, and how its useful for making more power.
I'm only asking because you said the pressure was created by heat.

Properly made header primaries radiate a minimal amount, on 22" long, 1.5"sch40 primaries I see under 50* from port to turbine.
 
burning fuel and air causes it to be hot :confused:

sounds like there isn't a lot of heat loss from radiating... Have you tried coating/wrapping to see what it does?

I liked my equal length header... very low egt's :D
 
Forrest Nearing said:
burning fuel and air causes it to be hot :confused:

sounds like there isn't a lot of heat loss from radiating... Have you tried coating/wrapping to see what it does?

I liked my equal length header... very low egt's :D
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At a minimum I internally coat all my headers, some get wrapped but I have never done any before and after testing of the wrap.
 
I know on the thinwall stuff, the headers would disintegrate from the heat, but we weren't coating the inside.

you probably wouldn't be able to quantify anything with your thick wall stuff, but it would be interesting to try and put all this to bed :D
 
Forrest Nearing said:
I know on the thinwall stuff, the headers would disintegrate from the heat, but we weren't coating the inside.

you probably wouldn't be able to quantify anything with your thick wall stuff, but it would be interesting to try and put all this to bed :D
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I've seen lots of sch40 headers, uncoated, glowing bright. With the coating on the ID and OD with some wrap I can put my hand on a primary when we do pull, however it is hot, but at least possible.
 
exhaust gas pushes the turbine.... HEAT expands the gas giving you more "push" to work with...

i don't see how any can argue this.

the "heat" part of the equation causes expansion.... more = more

you COULD blow cold air through a turbine and still make boost yes, but no as effieciently as hot, expanded gas....

am i wrong ?

cuz you 2 were going back and forth on this for awhile, and really to me.... how can you argue this ?
 
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