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It's been a minute, but I recall reading that the throttle plates in the itb's themselves are 50mm across. Unsure about the inner diameter of the itb if it's bigger. I know the Dinnan's are advertised as larger but can't seem to find how much larger.

Looked past the 3rd page on google and didn't see it.
 

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So you're keeping the velocity stacks in a larger pleum? That's a shame since they'd be great to see. You realize that the stock intake system already has a highly optimized plastic runners right? Again the PCM is calibrated to a certain airflow characteristic.
 

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that's what I thought and asked. Velocity stacks are ideal for naturally aspirated applications at high RPM, unclear why you would trouble with that when the intake system is pressurized. Just wondering what your logic was. 馃嵖
 

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I don鈥檛 understand why no one has yet made a turbo powered by an (electric) high RPM brushless motor... either direct mounted or dc motor + gears. I鈥檇 imagine it鈥檇 be 10x less in parts and setup required for SC or typical TT setup...
 

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an electric motor driven compressor? how much flow and boost would it be able to create? how much electrical energy would be needed?
please show some examples
 

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It would draw 100鈥漵 of amps

48v system would be required to minimize current draw and avoid further regulation issues
 

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Eaton has new SC models now and don't publish power curves anymore. But this gives you an idea of how much power is required to drive a supercharger. I randomly picked what seems to be one of their larger SCs so no idea if this properly sized to an S85 or not. That kW figure translates to little less than 100 hp.


At 12V you'd need 10500A, even at 48A you'll need 2625A. An industrial motor that size (100hp) would typically be a 500lb hog, 3-phase 575V like this:

 

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I don't get this - why not just get an F10? Slapping some turbos on a very high compression engine that already has issues with heat management seems like 2000s honda civic thing to do. You'll melt something down sooner or later, not unlike the e85 conversion guys.

Why would you need a new manifold? There's not enough space for twin intercoolers anyway.
 

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Turbocharging is specifically where you utilize the heat energy from internal combustion to perform additional work so that the engine can output even more work. The heat of the expanding waste gas does work (spins the turbine). The beauty of turbos is that it uses thermal energy that would otherwise go wasted. A properly engineered system places the turbo as close a possible to the exhaust port of the head. It really helps to understand thermal dynamics, but I am not going to go into this here because that is a full semester in the third year of a engineering degree.

An "electric turbo" really is just supercharging, it is NOT a true turbo, it (mis)uses the term. Elon Musk is a perfect example of misusing the term supercharging to talk about his EV charger, and Turbo mode which has no turbo.

Another purely aesthetic issue is that the turbos are also going to change the otherwise beautiful exhaust note.

Looking forward to see what the build looks like.
 

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I don't get this - why not just get an F10? Slapping some turbos on a very high compression engine that already has issues with heat management seems like 2000s honda civic thing to do. You'll melt something down sooner or later, not unlike the e85 conversion guys.

Why would you need a new manifold? There's not enough space for twin intercoolers anyway.
Exactly.Exactly.Exactly.There is not enough frontal area on the e60 for a properly sized intercooler to reduce the charged air temp, so that will lead to pre-ignition especially with 12:1 CR. The PCM/DME will command max spark retard, so I can see situations where there is less power with a twin turbo setup than stock. I'm really interested in the build.
 

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I will be watching closely as well. As I consider the discussion my ships come to mind. The engine is two cycle so we use blowers at idle and slow speed to pressurize the air box. Once there is enough exhaust heat to drive the turbos the air box pressure rises and the blowers cut out. Any form of blower/ electric turbo that reduces vacuum would have a benefit.

The real problem is the rod bearings. Currently the peak firing pressure is to high and the surface area to small to distribute the load over a long period of time. If you added more fuel and air the peak pressure would rise and you would reduce the bearing load by retarding the timing. On our engines we can look at the PV diagram in real time and make adjustments to balance the engine. You can always make more power you just reduce the service life of the parts.

Turbos are king now that we can tightly control fuel timing, amount and ignition timing. As an added bonus when can control valve timing. There are plenty of dino engines and drag engines, short service life. To build a real driver you always have to compromise for longevity. Like in Nascar they have a different engine build for each track.

For my part I would pull the bumper cover, headlights air boxes and headers. mount the turbos up front. The intake would stick out the front and the exhaust would go up through the hood. The header to the turbo really doesn't matter that much. You have oil and coolant lines up there as well. Most of the turbos use V-clamps to allow you to rotate the inlet and outlet. I would start small because you really don't need much boost to get a lot more kick out of the engine.

When I get into projects I try and take it one step at a time. If you get the turbos on and hooked up and the engine running that is the biggest step. You can always go back and re-plumb the piping, add coolers and what not. The oil cooler is in a perfect spot for an inter cooler. You could also consider adding an oil to water cooler or and air to water cooler. If you did water to air it would be more compact and you could use ice as well. I really dig this stuff except for the engine management, that is a real craft. As a marine engineer I am a jack of all trades and a mater of non.
 

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Discussion Starter #38
I need an intake manifold to ensure I don鈥檛 crack the frail factory plastic unit. The intake manifold will be the first item I will tackle.

I have 2 very trusted fabricators excluding myself and a very well known tuner who is chomping at the bit for the build.I鈥檓 not a name dropper but will give props as it comes together.

Heat will be a small hurdle to overcome. High temp coatings will work to keep under hood temps down and a large secondary oil cooler will handle the internal temp. Meth injection will keep the charge cooler.

Intercooling will be handled by air to air for phase 1. If IAT is too much for phase 2, air to water will be needed.

Im looking to be ready to tune for summer. Why not a F10? Because I can鈥檛 buy a $15k clean title F10. Additionally, I鈥檓 not looking to bolt on and tune a car that is already over the 900hp mark. I鈥檓 looking to break the mold. It鈥檚 more of a personal challenge at this point....
 

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I doubt there will ever be any progress on this. It just doesn't make sense on our platform. I'd love a TT setup as much as the next guy, but it's just never going to happen.
 
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