Adding a turbo to my Xf
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From: Mid-Michigan
Re: Adding a turbo to my Xf
Originally Posted by msheredy
I wonder though if they really understand that we share the same powertrain?
http://www.jetchip.com/products.asp?...&model=854#854
http://www.jetchip.com/purchase.asp?...478&part=65003
Contact Info:
http://www.jetchip.com/contact.asp
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Joined: Dec 2006
Posts: 953
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From: San Diego, CA
Re: Adding a turbo to my Xf
Originally Posted by RPM
I don't know. The tech I talked to seemed to know that they were basically the same car. You can give it a try if you would like. Maybe if they get enough calls, they'll do it:
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Joined: Jan 2007
Posts: 3,062
Likes: 1
From: Mid-Michigan
Re: Adding a turbo to my Xf
Originally Posted by msheredy
I just shot them an e-mail. Since I live in San Diego I said that I can drive up there to see what they can do. The power gains advertised (although not our model) look very promising indeed at a reasonable cost to boot! Thanks for the links!
Jet makes good stuff. Their performance chips are very popular. I had one on my old 2001 Silverado 5.3 V8 and it was NICE.
Keep me posted.
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Joined: Dec 2006
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From: San Diego, CA
Re: Adding a turbo to my Xf
Originally Posted by AMGLover
...I have been thinking of the paddle shifters with the speedshift upgraded ECU shift patterns...1,400 euros.
Originally Posted by AMGLover
btw a turbo wouldn't do much in this case...why do you think they picked a supercharger for this engine? (hint count the valves)
Here is the article from a fellow named Bill Watson of Garratt/Honeywell that sealed the deal (for me) to make the decision on the turbocharger. It's a long read but extremely informative. Here is the link as well.
http://www.hotrod.com/techarticles/t...er_comparison/
Originally Posted by HotRod.com
Online Editor’s note: The November ’01 issue of Hot Rod featured an extraordinary twin-turbo ’66 Mustang owned by Bill Watson, a jet engineer with Garrett/Honeywell. He generously supplied us with way more detail on his project car that we could fit in that issue, so we decided to include this question-and-answer interview that explains why he considers turbocharging superior to either supercharging or stroking an engine for more power. You may not agree with all of his points, but he knows his stuff. (After all, his Fastback runs in the 11s on—get this—SlimFast 215-section tires!) Blower buffs are invited to email us their alternative views on the best way to obtain boost.
Q: Other than the fact that the company you work for makes turbos, why go the turbo route? Why not use a supercharger or build a stroker? Are turbos simply the most efficient way to go?
A:There are four main reasons why I think turbos are superior to a blower, but of course I can’t argue that the supercharger isn’t easier. It is. I can appreciate why supercharger kits are more popular for the bolt-on crowd. But here are the reasons that I prefer turbos:
1) Turbos always will outperform supercharged cars when it comes to power production. It’s simple—you don’t have to spend (for instance) 70 crankshaft horsepower to drive compressors by taking engine horsepower right back off the crank. True, you back-pressure the engine on a turbo car, but much of the compressor horsepower comes from heat—and that is "free." The bottom line is that you don’t sap as much power out of the engine to get your pressurized air.
2) Easily adjustable boost! It’s a breeze to set up a **** inside the passenger compartment to adjust the wastegate setting up or down. When I drive in the mountains, I can raise boost to get back the power lost at higher altitudes. On the other hand, if I buy cheap gas I can turn it down, or change boost to compensate for summer or winter air temperatures (or for that matter, morning or evening temps too!). With a blower car you have to change pulleys—not that hard, mind you, but very few people are going to change pulleys as they’re climbing mountains, or at a gas station after buying a tank of cheap gas.
3) Midrange torque!! Boost vs. rpm is far superior on a turbo car. With a belt-driven centrifugal blower, you have to choose a pulley size so you won’t overboost at redline. But that means that at every rpm below that, you aren’t running as much boost as you can. The nature of centrifugal blowers is parabolic, meaning at half the redline rpm, you make less than half of the boost. So on a typical 5.0L, you might only make 3 psi of boost at 3,000 rpm, where a turbo car can easily be on the wastegate for 11 psi. That’s why I make 550 lb-ft at 3,000 rpm. Hey, if you cut my boost to 3 psi at 3,000, my torque would be down to 340—that’s 200 lb-ft less! To me, the best way to optimize a belt-driven centrifugal blower car would be to loosen the torque converter. Then you can hit the gas, immediately be at 4,000 rpm for example, make boost in an instant, and have a bolt-on car that just hauls. The only downside there is the economy will take a hit unless you can design in a lockup converter when you want to just cruise down the freeway. The turbo doesn’t have any of these compromises.
4) Finally, turbos run proportional to demand. What I’m getting at is that compressor speed is dependent on airflow, which comes from two main variables: engine rpm and throttle position, if you will. Now, a belt-driven blower car’s compressor speed is dependent on only one variable: rpm. So why care? Because when you’re just maintaining speed on flat and level ground, trying to make some mileage, a turbo car’s compressors are going very slowly and hence don’t increase pressure before the throttle body. But a belt-driven blower car has no idea what the throttle position is; the compressor is simply geared to the crankshaft, so it’s spinning much faster and making, say 2 psi in our example here. (And if it’s a Roots-type blower, it’s making 6, 8, or even 10 psi!)
So what do you do? You have to back out of the throttle even more. That means throttling losses are up (bad for mileage), and you’re pumping hot compressed air through your intercooler all day if you have one, and you’re using crankshaft horsepower to compress the air—then throttling it back anyway! At least put the throttle body before a blower; you can see why positive displacement (Roots or screw compressors) blowers have the throttle plate before them to avoid this problem. Then it’s much more of a non-issue.
You’ve also asked why I didn’t go to more cubic inches. Of course that works, but as you note the mileage wouldn’t be as good, plus I’d still have to build a 7,000 rpm motor to make this kind of power on something under 400 cubes. Then that requires all the money for rpm-related hardware to accommodate moving the operating range up, which I have spent zero dollars on. The turbo approach was different, in the sense that you spend the same money but on different hardware. I’ve done the cam/carb/intake/heads/headers/loose converter thing before. It was fun, but this time I wanted something that was a real sleeper until you lean on it.
Q: Surely you could have in theory used a stock intake, or not? Why not? What was the practical reasoning behind the intake design? Longer tubes equals greater torque?
A: Yes, I could have used a stock intake, but there were two big reasons I didn’t. One, the upper intake is extremely visible and typically is where most people’s eyes go when a hood is raised. This is where it’s easy to set the car apart from the others and do something different.
Two, when a stock intake is used on early Mustangs, the throttle body and the chassis bracing (the "export brace") can’t co-exist without cutting things up. I valued the export brace’s contribution to chassis stiffness enough to leave it intact. (I still need to work in the other option, a "Monte Carlo bar" that is common on early Mustangs which goes straight across from shock tower to shock tower. I used to run one but the latest mods required me to yank it for a while.
In addition, I was trying to maximize tube length for good bottom end torque, hence the runner shape going all the way to the valve covers. By most hot rod standards, 302 cubic inches isn’t a ton of displacement, so I wanted to maximize torque down where it would be driven. Plus, as you’ll note below, it allows you to run larger turbine nozzles so you can make more top end, too.
Q: Any idea how long intake runners are currently versus stock intake?
A: They’re about the same length, maybe an inch longer. Even a stock car with stock cam has a torque peak around 3,250 rpm, so I figured the headwork and larger diameter intake tubes would allow torque to hold on longer before starting to drop off, and I expected it to have peak torque around 3,600 to 3,800 or so. Hey, torque at 3,000 is 265 lb-ft normally aspirated (550 with 11 psi) and it was a pleasant surprise to find the torque just kept climbing between 3,000 and 4,100, for normally aspirated and blown peaks of 314 and 620 lb-ft, respectively. What great mid-range! I’m not Edelbrock, so I only had one attempt on this intake. I got lucky—it works better than I expected.
Q: How much boost are you running?
A: 11 psi. It was only the second night out at the track. This winter I’m sure we’ll go back with just a little more—it’s addictive.
Q: Does each turbo run 11 psi or is that total? Does that work out to 5 or 6 lbs per side, or does the pressure add or square itself?
A: Pressure doesn’t add. Each turbo runs 11 psi. Essentially I’ve got two 2.5L, four-cylinder engines here with a common crankshaft. The two turbo systems do interface together in the common intercooler and throttle body, but it is still important for me to set up both wastegates to open at the same pressure so one side of the engine isn’t back pressured more than the other by doing more than 50 percent of the compressor work.
Q: Why one throttle body, versus twin 57s as on the Ford Lightning or Mustang Bullitt, where each could feed its own half of the engine?
Q: Other than the fact that the company you work for makes turbos, why go the turbo route? Why not use a supercharger or build a stroker? Are turbos simply the most efficient way to go?
A:There are four main reasons why I think turbos are superior to a blower, but of course I can’t argue that the supercharger isn’t easier. It is. I can appreciate why supercharger kits are more popular for the bolt-on crowd. But here are the reasons that I prefer turbos:
1) Turbos always will outperform supercharged cars when it comes to power production. It’s simple—you don’t have to spend (for instance) 70 crankshaft horsepower to drive compressors by taking engine horsepower right back off the crank. True, you back-pressure the engine on a turbo car, but much of the compressor horsepower comes from heat—and that is "free." The bottom line is that you don’t sap as much power out of the engine to get your pressurized air.
2) Easily adjustable boost! It’s a breeze to set up a **** inside the passenger compartment to adjust the wastegate setting up or down. When I drive in the mountains, I can raise boost to get back the power lost at higher altitudes. On the other hand, if I buy cheap gas I can turn it down, or change boost to compensate for summer or winter air temperatures (or for that matter, morning or evening temps too!). With a blower car you have to change pulleys—not that hard, mind you, but very few people are going to change pulleys as they’re climbing mountains, or at a gas station after buying a tank of cheap gas.
3) Midrange torque!! Boost vs. rpm is far superior on a turbo car. With a belt-driven centrifugal blower, you have to choose a pulley size so you won’t overboost at redline. But that means that at every rpm below that, you aren’t running as much boost as you can. The nature of centrifugal blowers is parabolic, meaning at half the redline rpm, you make less than half of the boost. So on a typical 5.0L, you might only make 3 psi of boost at 3,000 rpm, where a turbo car can easily be on the wastegate for 11 psi. That’s why I make 550 lb-ft at 3,000 rpm. Hey, if you cut my boost to 3 psi at 3,000, my torque would be down to 340—that’s 200 lb-ft less! To me, the best way to optimize a belt-driven centrifugal blower car would be to loosen the torque converter. Then you can hit the gas, immediately be at 4,000 rpm for example, make boost in an instant, and have a bolt-on car that just hauls. The only downside there is the economy will take a hit unless you can design in a lockup converter when you want to just cruise down the freeway. The turbo doesn’t have any of these compromises.
4) Finally, turbos run proportional to demand. What I’m getting at is that compressor speed is dependent on airflow, which comes from two main variables: engine rpm and throttle position, if you will. Now, a belt-driven blower car’s compressor speed is dependent on only one variable: rpm. So why care? Because when you’re just maintaining speed on flat and level ground, trying to make some mileage, a turbo car’s compressors are going very slowly and hence don’t increase pressure before the throttle body. But a belt-driven blower car has no idea what the throttle position is; the compressor is simply geared to the crankshaft, so it’s spinning much faster and making, say 2 psi in our example here. (And if it’s a Roots-type blower, it’s making 6, 8, or even 10 psi!)
So what do you do? You have to back out of the throttle even more. That means throttling losses are up (bad for mileage), and you’re pumping hot compressed air through your intercooler all day if you have one, and you’re using crankshaft horsepower to compress the air—then throttling it back anyway! At least put the throttle body before a blower; you can see why positive displacement (Roots or screw compressors) blowers have the throttle plate before them to avoid this problem. Then it’s much more of a non-issue.
You’ve also asked why I didn’t go to more cubic inches. Of course that works, but as you note the mileage wouldn’t be as good, plus I’d still have to build a 7,000 rpm motor to make this kind of power on something under 400 cubes. Then that requires all the money for rpm-related hardware to accommodate moving the operating range up, which I have spent zero dollars on. The turbo approach was different, in the sense that you spend the same money but on different hardware. I’ve done the cam/carb/intake/heads/headers/loose converter thing before. It was fun, but this time I wanted something that was a real sleeper until you lean on it.
Q: Surely you could have in theory used a stock intake, or not? Why not? What was the practical reasoning behind the intake design? Longer tubes equals greater torque?
A: Yes, I could have used a stock intake, but there were two big reasons I didn’t. One, the upper intake is extremely visible and typically is where most people’s eyes go when a hood is raised. This is where it’s easy to set the car apart from the others and do something different.
Two, when a stock intake is used on early Mustangs, the throttle body and the chassis bracing (the "export brace") can’t co-exist without cutting things up. I valued the export brace’s contribution to chassis stiffness enough to leave it intact. (I still need to work in the other option, a "Monte Carlo bar" that is common on early Mustangs which goes straight across from shock tower to shock tower. I used to run one but the latest mods required me to yank it for a while.
In addition, I was trying to maximize tube length for good bottom end torque, hence the runner shape going all the way to the valve covers. By most hot rod standards, 302 cubic inches isn’t a ton of displacement, so I wanted to maximize torque down where it would be driven. Plus, as you’ll note below, it allows you to run larger turbine nozzles so you can make more top end, too.
Q: Any idea how long intake runners are currently versus stock intake?
A: They’re about the same length, maybe an inch longer. Even a stock car with stock cam has a torque peak around 3,250 rpm, so I figured the headwork and larger diameter intake tubes would allow torque to hold on longer before starting to drop off, and I expected it to have peak torque around 3,600 to 3,800 or so. Hey, torque at 3,000 is 265 lb-ft normally aspirated (550 with 11 psi) and it was a pleasant surprise to find the torque just kept climbing between 3,000 and 4,100, for normally aspirated and blown peaks of 314 and 620 lb-ft, respectively. What great mid-range! I’m not Edelbrock, so I only had one attempt on this intake. I got lucky—it works better than I expected.
Q: How much boost are you running?
A: 11 psi. It was only the second night out at the track. This winter I’m sure we’ll go back with just a little more—it’s addictive.
Q: Does each turbo run 11 psi or is that total? Does that work out to 5 or 6 lbs per side, or does the pressure add or square itself?
A: Pressure doesn’t add. Each turbo runs 11 psi. Essentially I’ve got two 2.5L, four-cylinder engines here with a common crankshaft. The two turbo systems do interface together in the common intercooler and throttle body, but it is still important for me to set up both wastegates to open at the same pressure so one side of the engine isn’t back pressured more than the other by doing more than 50 percent of the compressor work.
Q: Why one throttle body, versus twin 57s as on the Ford Lightning or Mustang Bullitt, where each could feed its own half of the engine?
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Posts: 953
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From: San Diego, CA
Re: Adding a turbo to my Xf
Continued from previous article.
Originally Posted by HotRod.com
A: For the reasons above, I didn’t want two totally divorced turbo systems. Besides, when I started this project four years ago, the aftermarket was clearly more oriented to the single TB.
Q: As we photographed the car, you mentioned choosing (among other things) gear ratio, intercooler size, and the backpressure-to-boost-ratio work to select turbine nozzles. How did you decide on these? Are any of them slightly overkill with some extra built in, or are they just right for the job and will need to be changed if something else changes?
A: Intercooler size is somewhat like fuel-line size or air conditioning condenser size—you almost can’t make them too big. The entire goal for an intercooler is maximum cooling and minimum pressure drop. As you make them bigger the cooling always gets better, but just making an air-to-air intercooler taller eventually starts increasing pressure drop, which of course is bad. There’s some juggling there where it actually gets worse. The water intercooler I selected is the biggest one I could squeeze under the fender without mods, and the beauty is that it’s exactly twice the size of many 5.0L and 5.7 Chevy aftermarket water-air intercoolers, but they are just dying for more available room. At twice that size, it calculated out pretty well. Once you decide to intercool, it’s a bad place to cut corners to try and save a buck.
Gear ratio is, on the other hand, just like you said; you size it for the job and it might need to be changed if something else changes. I make plots of this all the time. If you are a drag racer the trap speed is very much tied to the power production in the last quarter of the track. If you’ve just shifted into the next gear at the 900 foot point and are groaning the car at 4000 rpm (not peak power in this example!!) your trap speed will clearly suffer. Optimum gear for this car today is 3.60 if drag racing were my only criteria. As soon as I add 50 horsepower, this figure drops (like maybe to 3.40) because you still want to cross the traps at the power peak, and obviously the increase in power will manifest itself as more trap speed—hence the gear-change requirement.
Also, in a turbo car, boost vs. rpm is a transient event, so with a 5-speed, you really have five different torque curves to design for. By gearing the car steeper (4.11, 4.56, etc), engine rpm grows faster than boost can keep up if you will, so in a rpm-sense, this is slowing down boost response. Add on top of this the fact that the effective mass of the rotating group of the engine goes up with gear ratio squared. So there are two downsides to more gear, while the obvious up-side is the increase in torque multiplication (which is why people do it in the first place). This is definitely a juggling act, and turbo cars for this reason tend to do better than expected with slightly taller gears because they have two downsides fighting the up-side, not just one vs. one when you’re normally aspirated.
Turbine nozzles are also a compromise. Much like selecting a camshaft, you’re essentially trading top-end for bottom-end power. This one is very hard to do analytically before you build your turbo system, so you shoot from the hip as best you can, then test the system once it’s together. I use the back-pressure/boost ratio as one of the evaluation tools.
Here’s a little background to appreciate the exchange of bottom end for top end: If you run little nozzles the boost response is early and you’ll make more power at 2,000 rpm than you would have with a bigger nozzle because of the increased boost. However, the downside is that your back pressure will be higher with the small nozzles on the top end because the wastegates are open and less and less of your exhaust has to do "all the compressor work." What do I mean? If memory serves me correctly, it takes around 60 to 70 compressor horsepower to supply my engine with 11 psi compressed air at 6,000 rpm from the turbo’s compressors. Where does this energy come from? Exhaust heat (which is "free") and exhaust back pressure (not free). With really big turbine nozzles, (no wastegates), 100 percent of my exhaust generates this work and back pressures the motor minimally, less than 11 psi, in fact. With really small turbine nozzles, the majority of exhaust is going through the wastegate (not through the turbine) to keep the compressor from overspeeding. Thus, if you will, "40 percent" of my exhaust has to do all the compressor work. If there’s less flow through the turbine but you need the same power, it must be accompanied by a higher pressure—you guessed it—back pressure.
Anyway, the point is that I do measure the back pressure and compare it to boost because turbo cars are notorious for having exhaust go up the intake during overlap. Lots of cars have back pressure that is two, even three times boost pressure. This is why turbo cars have the reputation of loving cams with tons of lobe separation, which minimizes the time when both valves are open and this problem occurs. If you’re Joe Bonneville, you’ll run huge nozzles, have low back pressure to boost, and traditionally run closer lobe centers just like anyone in the normally aspirated racing world, since your back pressure to boost ratio is much like theirs. Back pressure testing is important on n/a cars, but even more important on turbo cars as it helps you size the turbine nozzles.
Q: As we photographed the car, you mentioned choosing (among other things) gear ratio, intercooler size, and the backpressure-to-boost-ratio work to select turbine nozzles. How did you decide on these? Are any of them slightly overkill with some extra built in, or are they just right for the job and will need to be changed if something else changes?
A: Intercooler size is somewhat like fuel-line size or air conditioning condenser size—you almost can’t make them too big. The entire goal for an intercooler is maximum cooling and minimum pressure drop. As you make them bigger the cooling always gets better, but just making an air-to-air intercooler taller eventually starts increasing pressure drop, which of course is bad. There’s some juggling there where it actually gets worse. The water intercooler I selected is the biggest one I could squeeze under the fender without mods, and the beauty is that it’s exactly twice the size of many 5.0L and 5.7 Chevy aftermarket water-air intercoolers, but they are just dying for more available room. At twice that size, it calculated out pretty well. Once you decide to intercool, it’s a bad place to cut corners to try and save a buck.
Gear ratio is, on the other hand, just like you said; you size it for the job and it might need to be changed if something else changes. I make plots of this all the time. If you are a drag racer the trap speed is very much tied to the power production in the last quarter of the track. If you’ve just shifted into the next gear at the 900 foot point and are groaning the car at 4000 rpm (not peak power in this example!!) your trap speed will clearly suffer. Optimum gear for this car today is 3.60 if drag racing were my only criteria. As soon as I add 50 horsepower, this figure drops (like maybe to 3.40) because you still want to cross the traps at the power peak, and obviously the increase in power will manifest itself as more trap speed—hence the gear-change requirement.
Also, in a turbo car, boost vs. rpm is a transient event, so with a 5-speed, you really have five different torque curves to design for. By gearing the car steeper (4.11, 4.56, etc), engine rpm grows faster than boost can keep up if you will, so in a rpm-sense, this is slowing down boost response. Add on top of this the fact that the effective mass of the rotating group of the engine goes up with gear ratio squared. So there are two downsides to more gear, while the obvious up-side is the increase in torque multiplication (which is why people do it in the first place). This is definitely a juggling act, and turbo cars for this reason tend to do better than expected with slightly taller gears because they have two downsides fighting the up-side, not just one vs. one when you’re normally aspirated.
Turbine nozzles are also a compromise. Much like selecting a camshaft, you’re essentially trading top-end for bottom-end power. This one is very hard to do analytically before you build your turbo system, so you shoot from the hip as best you can, then test the system once it’s together. I use the back-pressure/boost ratio as one of the evaluation tools.
Here’s a little background to appreciate the exchange of bottom end for top end: If you run little nozzles the boost response is early and you’ll make more power at 2,000 rpm than you would have with a bigger nozzle because of the increased boost. However, the downside is that your back pressure will be higher with the small nozzles on the top end because the wastegates are open and less and less of your exhaust has to do "all the compressor work." What do I mean? If memory serves me correctly, it takes around 60 to 70 compressor horsepower to supply my engine with 11 psi compressed air at 6,000 rpm from the turbo’s compressors. Where does this energy come from? Exhaust heat (which is "free") and exhaust back pressure (not free). With really big turbine nozzles, (no wastegates), 100 percent of my exhaust generates this work and back pressures the motor minimally, less than 11 psi, in fact. With really small turbine nozzles, the majority of exhaust is going through the wastegate (not through the turbine) to keep the compressor from overspeeding. Thus, if you will, "40 percent" of my exhaust has to do all the compressor work. If there’s less flow through the turbine but you need the same power, it must be accompanied by a higher pressure—you guessed it—back pressure.
Anyway, the point is that I do measure the back pressure and compare it to boost because turbo cars are notorious for having exhaust go up the intake during overlap. Lots of cars have back pressure that is two, even three times boost pressure. This is why turbo cars have the reputation of loving cams with tons of lobe separation, which minimizes the time when both valves are open and this problem occurs. If you’re Joe Bonneville, you’ll run huge nozzles, have low back pressure to boost, and traditionally run closer lobe centers just like anyone in the normally aspirated racing world, since your back pressure to boost ratio is much like theirs. Back pressure testing is important on n/a cars, but even more important on turbo cars as it helps you size the turbine nozzles.
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Joined: Dec 2006
Posts: 953
Likes: 1
From: San Diego, CA
Re: Adding a turbo to my Xf
Originally Posted by AMGLover
Well I would be skeptical since it is the same ECU upgrade for all slk's and the SLK32 and SLK 55 are night and day power platforms.
- ej
- ej
Actually it must be a model year break. All the cars prior to the CL500 have a different part number.
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Joined: Dec 2006
Posts: 953
Likes: 1
From: San Diego, CA
Re: Adding a turbo to my Xf
Originally Posted by AMGLover
Good read but a couple of things.
1) Garret is one of the worlds biggest turbocharger maker - so the guy is a bit biased.
1) Garret is one of the worlds biggest turbocharger maker - so the guy is a bit biased.
Originally Posted by AMGLover
2) The AMG engine is unique in that it uses a helical NOT a centrifugal blower.
Originally Posted by AMGLover
4) Torque curve! P.S. only one exhaust valve per cylinder on the M112.
Originally Posted by AMGLover
So what do you want a shade tree turbo, or the worlds best supercharger...
http://autospeed.drive.com.au/cms/A_1447/article.html
After reading the article you will see that the supercharger is actually turned off at higher RPMs and the turbos take over. Over all boost only increased by 3ibs but look at the horsepower... 500 of them! I know that he could have made everything simpler by removing the supercharger completely and still have the high horsepower figures.
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Joined: Dec 2006
Posts: 2,881
Likes: 3
Re: Adding a turbo to my Xf
My vote goes to the helical blower over a turbo set up on a street car.
Turbos take time to spool up, even with all the new whiz-bang innovations in turbo technology. It still doesn't have the same response time as the blower. And who cares about the upper end of the powerband! I never run my engine over 4,000 rpm with the 6 speed because it has so much usable torque down low, I could care less about making full Hp at 5,600 rpm. Its just hard on an engine and kills reliability.
Turbo kit will require a lot of plumbing and intercooler, oil press line return lines, coolant inlet lines and return line, fabbed up exhaust manifolds to mount the turbo(s), and on and on, space is limited under the hood... just too much work to build a working unit, when all the engineering has be done for you with the SLK32. Why reinvent the wheel guys?
Turbos take time to spool up, even with all the new whiz-bang innovations in turbo technology. It still doesn't have the same response time as the blower. And who cares about the upper end of the powerband! I never run my engine over 4,000 rpm with the 6 speed because it has so much usable torque down low, I could care less about making full Hp at 5,600 rpm. Its just hard on an engine and kills reliability.
Turbo kit will require a lot of plumbing and intercooler, oil press line return lines, coolant inlet lines and return line, fabbed up exhaust manifolds to mount the turbo(s), and on and on, space is limited under the hood... just too much work to build a working unit, when all the engineering has be done for you with the SLK32. Why reinvent the wheel guys?
Last edited by Maxwell; Apr 26, 2007 at 05:56 PM.
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Joined: Dec 2006
Posts: 953
Likes: 1
From: San Diego, CA
Re: Adding a turbo to my Xf
Originally Posted by Maxwell
Turbos take time to spool up, even with all the new whiz-bang innovations in turbo technology.
Originally Posted by Maxwell
It still doesn't have the same response time as the blower.
Originally Posted by Maxwell
And who cares about the upper end of the powerband!
Originally Posted by Maxwell
Turbo kit will require a lot of plumbing and intercooler, oil press line return lines, coolant inlet lines and return line, fabbed up exhaust manifolds to mount the turbo(s), and on and on, space is limited under the hood... just too much work to build a working unit, when all the engineering has be done for you with the SLK32. Why reinvent the wheel guys?
Anyway, an STS turbo mounts in a remote location usually replacing the muffler. All that needs to be run is the air feed (to the throttle body) oil line & electrical (for the oil scavenger pump). I intend on using the factory intercooler on this setup. Why are you talking about coolant lines? You do realize that not all turbos are water cooled nor do they need to be.
Just do me a favor and try to see it this way. It's not re-inventing the wheel, it's like putting a piece of rubber on it... Got it?
Oh here's another one, if you aren't interested in this topic then why are you even posting here? Isn't the purpose of this forum to help one another, not shoot them down? It's comments and attitudes such as these that might keep this car from becoming what it truly deserves to be.
Last edited by msheredy; Apr 27, 2007 at 01:03 PM.
Senior Member
Joined: Jul 2005
Posts: 1,825
Likes: 19
Re: Adding a turbo to my Xf
I think one of the hardest parts of this project will be tuning the ECM.
I would start looking for a competent tuner who feels confident and work out the potential brick walls first.
Best of luck and keep us posted.
I would start looking for a competent tuner who feels confident and work out the potential brick walls first.
Best of luck and keep us posted.
Forum Regular
Joined: Dec 2006
Posts: 953
Likes: 1
From: San Diego, CA
Re: Adding a turbo to my Xf
Originally Posted by stryfox
I think one of the hardest parts of this project will be tuning the ECM.
Last edited by msheredy; Apr 27, 2007 at 01:17 PM.
Forum Regular
Joined: Dec 2006
Posts: 953
Likes: 1
From: San Diego, CA
Re: Adding a turbo to my Xf
Originally Posted by AMGLover
Ahh those crazy Aussie’s -STS turbos- whoo hoo! just don’t crack your turbo on a speed bump at the drive thru! Love that shot of the air filter on the LS1… plan to drive in the rain?
Originally Posted by STSturbo.com
Doesn't water get into your engine with the filter mounted down low? No, every kit includes either a snorkel kit which locates the air filter high in the rear quarter panel or an air filter shield. We also include an Outerwears Dry Charger which is a "sock" that protects the filter under very dusty or wet conditions. The only thing you don't want to do is completely submerge the filter. This would draw water through the filter and into the intake tubing. For most vehicles that would mean you would have water coming in your doors before you'd have a problem with the turbo's air filter.
Originally Posted by AMGLover
your ECU will be useless - fitment issues
Originally Posted by AMGLover
...why don’t we see it on Porches, Lambo’s, Ferrari’s etc...
http://www.egmcartech.com/2007/02/23...15-horsepower/
Horsepower TV has done an install and had nothing but good to say about it. (Read-no lag)
Originally Posted by AMGLover
Good luck with the conversion, and in the end any SRT-6 with equivalent mods to the S/C will spank yours on the track and in reliability.
I just keep asking myself, why do these people care what I do???
Forum Regular
Joined: Dec 2006
Posts: 953
Likes: 1
From: San Diego, CA
Re: Adding a turbo to my Xf
Originally Posted by bollox
I very much enjoyed this thread... First for a long time that has not been completely dominated by "senior members" (not being negative).
Forum Regular
Joined: Dec 2006
Posts: 953
Likes: 1
From: San Diego, CA
Re: Adding a turbo to my Xf
Originally Posted by AMGLover
Your not a mechanical engineer
Originally Posted by AMGLover
Have you even looked under the car?
Originally Posted by AMGLover
I’m not even going to talk about the SRT variant Bosch ME 2.8.1 and how it will torpedo your project, you obviously haven’t even done any research on the CANN.
Originally Posted by AMGLover
Well you just might need those lotto numbers with all the dollars your going to be pouring into this project.
Last edited by msheredy; Apr 27, 2007 at 05:07 PM.