Posted: 5/28/2006 7:27:33 AM EDT
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I saw an ad on Powerblock today and they installed one up on Two Cars Garage aparently. How the hell does it work? I mean the exhaust tip mounts right to the turbine and what not. I'm confused. If someone can enlighten me on wtf is going on, it would put my mind at ease. Here's what I'm talking about... Remote Turbo System |
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Alright, I did my homework... The stock exhaust right before the muffler mounts to the turbo. The output gets routed ALL THE WAY back to the engine compartment (lots of piping as far as I can tell). Meanwhile the turbo acts as a muffler kinda-sorta making for one hell of a turbo whine out the exhaust. Interesting.... The main downside I can see is have the air filter there. Hard rain could fuck it up hardcore style. Thoughts? |
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As I understand turbos, the longer the distance of the "loop" from the exhaust valve, thru the exhaust pipe spinning the turbo, and then the intake thru the turbo and back to the intake valve, the longer the "turbo lag" time involved. "Turbo lag" is the difference in the time you press your foot down on the accellerator pedal, to the time that you feel the turbo "kick in". This appears to be a "long lag time" type of turbo. Turbo lag time is one of the reasons that some people prefer superchargers, because superchargers don't have lag time in the design. |
On their website they claim to use turbos engineered for this loop, but yea I can see this being a very large problem. Superchargers on the downside use engine power in order to gain their boost, which robs power. This is all very intriquing. |
No problem, I'm sure they use a bypass on this design. The bypass valve will prevent water from getting into your motor if the air filter gets submerged. |
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From what I have seen online they are damned effective. I have been following this since the naysayers first started slamming STS on the remote mount turbo. Personally, its not how I would do things. That said, it introduces less heat to the engine compartment, is cheaper to install (no need for custom headers), and they do not require intercoolers in many applications because the long tube from the rear to the front of the car will help act as a heat sink. While they won't develop power to the very last drop like a conventional system, most folks would be hard pressed to notice. They DO make a lot of power, and are engineered to work in the remote location. One potential disadvantage not usually associated with conventional turbos: They can get "borrowed" with little more than a battery powered sawzall. |
| i saw this setup done on tv about a year ago and w/ out even tuning the camaro SS it added over 100 hp on 6 lbs of boost and the turbo was fully operable at 1500 rpm.....that's pretty effective w/ hardly any lag.....the only downside of this system is only one pipe coming out the back....so dual exhaust aren't existent (so on the looks side it's ugly) also if the car is lowered a lot of fabbing must be done in order to run all the pipes under the car and i've seen many where they run the pipes right thru the inside of the car.....which then you have to worry about heat....but anyways that's my two cents and yes the exhaust from the motor upon accelerating or giving it gas is what causes the turbo to spool so thats why there is hardly any lag |
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There would be a huge amount of lag over a similar system with less pipe volume. I have a WRX, and my intercooler is mounted on top of my engine in order to reduce the amount of volume in the piping (well, and to keep rocks off it in rally racing). When people switch to a more effective front mount, they noticably increase their lag. I can not imagine what the lag would be with enough pipe to reach the rear of a pickup. I am not saying the system does not work, or does not make good power, I am just saying the system would have alot more lag than a similar system |
| from a thermo point of view, moving the turbo to a cooler area does not do wonders for the efficiency. Also the purpose of the intercooler is to cool the air after it has been heated up by compressing not to reduce underhood temperature. Turbo lag has to be through the roof. Finally it looks like you'd have to replace the air filter on a weekly basis to ensure it wasn't robbing you of what little efficiency this rube goldberg system would provide. |
| One thing I don't like is the low placement of the turbo on the car. In the real world a car with this sysetm might be driver in the rain through puddles. While the turbo may run cooler in this location it still gets really hot. I would worry about the housing cracking if it was and suddenlly got water dumped on it. |
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Wow, there are a lot of misconceptions and right ideas rolled into one on this thread thus far. I will try to cover as many of them as possible, and address any remaining questions. 1. Water getting sucked into the turbo. I have read that it is a problem with this type of setup (read of this happening with F-body systems) I am sure that one could come up with a way to prevent it, althoug it would take more work than the kit makers seem to be putting into it. 2. Lag and my rant I am about fucking tired of hearing about turbo lag. Most people who use the expression have a vauge understanding of how the darn turbos work any way. Those that do don't usually understand how to avoid it. 2a. lag is defined for the purposes of this rant as the time it takes for a given turbo to reach full boost once the turbo hasz reached the boost threashold (the RPM the turbo spools up at). 2b. Properly sized IC piping will move a given vol. of air at about .3-.4x the speed of sound. I have never read of anyone who has experienced a perceptable increase in lag due to a larger IC or piping. If you have that is great but I don't want to hear your non-sense. 2c. I would agree that the remote mount systems are less efficient than their underhood counterparts. That being said, there is a lot of headway being made in ceramic coatings that is helping to deminish the heat/energy loss back to the turbine. One who is wise in the ways of turbos will realize that most of the systems offered that are designed for 342CID GMs have a turbine housing and wheel the size of the one in my 135CID Omni, and don't spool that much faster either. They loose the heat on the way back, and can't spin as large of a wheel as they could have if it was mounted under the hood. It is a fact of life that you can't have your cake and eat it too on this one. That lost heat energy could have been used to make more power. You can definatly do a lot with a turbo that is reativly far away from the head, but I doubt that most will be able to get the results that this guy does unless that they are doing it for an individual car like he is. 3. Intercooling in relation to R.T.S. I have read that the heat loss from the charge air on the way to the TB in a remote turbo system is enough that a IC is not really needed at lower boost levels. Although I would argue that at most of these boost levels I have seen, a properly sized turbo with apporpriate fuel mods would not need one either, this is neither here nor there. I would run the biggest one that would fit infront of the rad and call it a day, or use a chemical IC system such as alcohol. The IC in front of the rad is always my first choice though. I always like to point out that the same principal that is helping you on this side is raping you hard on the hot side. 4. Dual exhaust. If you really have to have dual exhaust just split the pipe after it comes off of the turbo. Any good custom exhaust place should be able to make you car look stock out back with one of these systems. If they can't your kit is set up in an assinine way or, you need to find a new custom exhaust shop. |
Sorry you can't shape an argument by making up definitions: # Within a turbocharger's operating range, lag is the dlay between the instant a car's accelerator is depressed and the time the turbocharged engine develops a large fraction of the power available at that point in the engine's power curve. www.clublexus.com/index.php/article/archive/119/36 # The time delay between injecting fuel to accelerate and delivering air to the intake manifold by the turbocharger. This phenomenon may cause black smoke emissions in some turbocharged diesel engines during acceleration. www.dieselnet.com/gl-s.html # The time that it takes a turbo to "spool up", or start working in its' most efficient range is called turbo lag. Think of it as a delay in the amount of time from when you depress the gas until the engine starts to speed up...the bigger the turbo, the longer the lag. But bigger turbos make more horsepower overall...the challenge is to use a turbo just big enough to give you that sudden rush of acceleration AND good power overall. www.thefastandfurious.info/tech/tech_index.htm # Turbo lag is the delay between when you press the throttle and the turbocharger starts producing boost pressure. Since a turbocharger is an exhaust driven compressor, the engine must be producing a sufficient quantity of exhaust gases to drive the turbocharger, which may only occur once the engine gets to a high rpm. Ways to reduce turbo lag are to lighten the turbocharger components to reduce inertia, use a smaller turbocharger, or use rally style anti-lag en.wikipedia.org/wiki/Turbo_lag |
#1 and #3 that you list agree with my definition. Moreover, I can cite the book maximum boost by Corky Bell as my reference. I do commend your google abilities though, as it must have taken some time to come up with those lack luster counterpoints. Good day. |
I have heard rumors that there is a second edition in the works. I know of a guy on another board who has talked with Corky about it, and given some opinions/advise. It has been a while since I heard about that though. So if it is coming along, it is doing so very slowly. |