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Originally posted by Resbum
In regards to a lot of energy, probably not. I might lose some, but I don't think so.
Bare with me for a moment here. This may seem off-topic, but it's not and I do get back around to your comment.
A little info about automotive history in the USA. Ten years before you could buy a turbocharged 2002 Subaru WRX in the US it was available, and very successful, around the rest of the world. Even then, the one we got in the States was underpowered compared to the ones around the rest of the world. Another example is the old Toyota Pickup and 4Runner. Anywhere else on Earth a person could buy one that came with a turbo diesel engine, even in Canada. Those engines never did make it to the US. These are just two examples, but ones I have personal experience with.
Why did these two cases happen? Because the US government makes our DOT and environmental laws so overly complex and expensive that it's not profitable to the automakers to jump through all the hoops to import those engines here.
Now my personal experience. I bought a 1999 Subaru Impreza RS and turbocharged it. When I was finally happy with how it ran it launched so hard it would got through first gear so fast that I'd bang the engine off the rev-limiter before I could shift to second gear. For those that don't know, Subaru uses flat-four engines like the old VW Bugs and Porsches. Because of this design it's almost impossible to have somewhat short, equal-length exhaust runners. In this case the shortest was around 1 1/2 feet and the longest was over 4 feet.
While I was building and refining this engine the one thing I did that had the biggest single affect on engine performance was change exhaust runner diameter. I bought an aftermarket header that had 1/4" bigger runners. That header introduced a very considerable lag in turbo response and I took it back off and sold it to a guy running normally aspirated. He absolutely loved it, but it sucked @$$ on a forced induction engine. Why? Because the larger diameter tubes slowed down the gas velocity. I ened up running the stock Subaru exhaust wrapped.
Here is a must read for anyone who likes to gain knowledge through reading. Corky Bell's book, "Maximum Boost". http://www.amazon.com/Maximum-Boost-.../dp/0837601606
It's an incredible resource about turbocharging.
The four things I took from it about spool up while building the Subaru is heat, velocity, compressor blade selection, and flow restriction. Match those and you're in the ballpark.
For my truck:
Heat- The hotter a gas the more volume a given amount will occupy. My extension is going to be ceramic coated and wrapped and I'll have very little heat loss through it. This is also why I had the Cummins manifold ceramic coated.
Velocity- It's the product of heat and volume. Because I won't lose much heat that won't affect velocity. The outlet of the manifold and inlet of the turbo both have two port-matched rectangles. I chose round tubes that have a very similiar cross-sectional area to those rectangles, so I shouldn't lose velocity going through larger volume tubes.
Compressor blade design- Both the BD Super B turbo and Colt cam I chose have quicker spool up over stock. Even if I have some loss through the turbo relocator the turbo and cam will probably make up the difference.
Flow restriction- My original plan had the gasses making two tight turns in opposite directions. That is more disruptive to flow than having the gasses make a longer, more gradual, 360 degree loop.
With all of that long-winded typing behind me I can say I don't really expect the turbo relocator will have much adverse affect on performance. If it does I'll just have to live with it since there's no way I can run a turbo without it.
Resbum
Bare with me for a moment here. This may seem off-topic, but it's not and I do get back around to your comment.
A little info about automotive history in the USA. Ten years before you could buy a turbocharged 2002 Subaru WRX in the US it was available, and very successful, around the rest of the world. Even then, the one we got in the States was underpowered compared to the ones around the rest of the world. Another example is the old Toyota Pickup and 4Runner. Anywhere else on Earth a person could buy one that came with a turbo diesel engine, even in Canada. Those engines never did make it to the US. These are just two examples, but ones I have personal experience with.
Why did these two cases happen? Because the US government makes our DOT and environmental laws so overly complex and expensive that it's not profitable to the automakers to jump through all the hoops to import those engines here.
Now my personal experience. I bought a 1999 Subaru Impreza RS and turbocharged it. When I was finally happy with how it ran it launched so hard it would got through first gear so fast that I'd bang the engine off the rev-limiter before I could shift to second gear. For those that don't know, Subaru uses flat-four engines like the old VW Bugs and Porsches. Because of this design it's almost impossible to have somewhat short, equal-length exhaust runners. In this case the shortest was around 1 1/2 feet and the longest was over 4 feet.
While I was building and refining this engine the one thing I did that had the biggest single affect on engine performance was change exhaust runner diameter. I bought an aftermarket header that had 1/4" bigger runners. That header introduced a very considerable lag in turbo response and I took it back off and sold it to a guy running normally aspirated. He absolutely loved it, but it sucked @$$ on a forced induction engine. Why? Because the larger diameter tubes slowed down the gas velocity. I ened up running the stock Subaru exhaust wrapped.
Here is a must read for anyone who likes to gain knowledge through reading. Corky Bell's book, "Maximum Boost". http://www.amazon.com/Maximum-Boost-.../dp/0837601606
It's an incredible resource about turbocharging.
The four things I took from it about spool up while building the Subaru is heat, velocity, compressor blade selection, and flow restriction. Match those and you're in the ballpark.
For my truck:
Heat- The hotter a gas the more volume a given amount will occupy. My extension is going to be ceramic coated and wrapped and I'll have very little heat loss through it. This is also why I had the Cummins manifold ceramic coated.
Velocity- It's the product of heat and volume. Because I won't lose much heat that won't affect velocity. The outlet of the manifold and inlet of the turbo both have two port-matched rectangles. I chose round tubes that have a very similiar cross-sectional area to those rectangles, so I shouldn't lose velocity going through larger volume tubes.
Compressor blade design- Both the BD Super B turbo and Colt cam I chose have quicker spool up over stock. Even if I have some loss through the turbo relocator the turbo and cam will probably make up the difference.
Flow restriction- My original plan had the gasses making two tight turns in opposite directions. That is more disruptive to flow than having the gasses make a longer, more gradual, 360 degree loop.
With all of that long-winded typing behind me I can say I don't really expect the turbo relocator will have much adverse affect on performance. If it does I'll just have to live with it since there's no way I can run a turbo without it.
Resbum
[FONT='MS Shell Dlg 2','sans-serif']1. I love your deisel build. What an inspiration! [/FONT]
[FONT='MS Shell Dlg 2','sans-serif'] 2. I love the brief rundown on US automotive history and turbo/ diesel engine constraining by departmental regulation. [/FONT]
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[FONT='MS Shell Dlg 2','sans-serif']Here in Aus we have been lucky. We have been able to obtain all the models you speak of and more in turbo diesel. Now the market here is at an advanced stage for TD engines. DOHC 4 Valve/ cyl heads, high pressure CRD, VGT?s and intercooling is now just par for the course?[/FONT]
[FONT='MS Shell Dlg 2','sans-serif'][FONT='MS Shell Dlg 2','sans-serif'][/FONT]
[FONT='MS Shell Dlg 2','sans-serif']My 010 D90 has all of that crammed into the remainder of its archaic design. A small displacement Ford diesel. It is truly a miraculous engine and along with the six speed box - the highlight of the car! [/FONT]
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[FONT='MS Shell Dlg 2','sans-serif'] [/FONT]
[FONT='Verdana','sans-serif']Velocity- It's the product of heat and volume[/FONT][FONT='MS Shell Dlg 2','sans-serif'] ? Not exactly. Indirectly - definitetly. With higher temps you have higher operating pressures in your system correct? Are you expecting this to increase velocity?[/FONT]
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