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Discussion Starter · #1 ·
I bought a electric supercharger its from a Audi SQ7 4.0 tdi for those who want to know. the unit is made by valeo part number 057145601D /F

im going to run it on a bmw 320d E90 2006 but ill be keeping the original turbocharger as well this one will just be for initial boost so it will be bursts of power not constant and i believe the amps calculated out at 146a. correct me if im wrong.

anyway im in need of a battery or battery pack and it needs 48v and its a 7kw system i would like something that's compact where possible (i know that might be a problem) while i have a fair bit of space its not unlimited of course.

any idea's suggestions and comments are welcome. please understand i don't want a supercharger i dont have the room in the right place to put one but i do have a lot of space in the engine bay as well. I plan to fit the turbo above the existing one there was a very large airbox there which is now gone so there is plenty of space for the electric turbocharger, i could fit 2 of them if it wasnt for the need of the extra battery power lol. . Also the egr cooler has been removed so that means i can access the coolant lines easily should i need them not sure if i would need another radiator for coolant for the turbo but there is enough room if i do need one.


i got a space under the boot carpet the biggest area could fit 2 standard car batteries with lots of height above them and i got a small shallow area next to it and also a larger shallow area the width of the first 2 mentioned. so plenty of places to put things in the boot under the carpet and if need be i have some room above it at the sides i could use as well. in the engine bay i got maybe a foot in front of the engine which stretches out to the sides theres more space behind the right headlight (as your standing in front of it) could fit a big airbox there as an example of the space.

i should do a video really if anyone wants to see all the space ive got i will. i hope ive given all the information needed if not please ask.

Thanks in advance
 

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You want to mount the batteries as close as possible to the supercharger to minimise the weight of the wires connecting them and the losses in them.
Do you have an idea of what the duty cycle of the supercharger is going to be? The hybrid battery from something like a Fiesta would seem appropriate based on a few guesses.


HYBRID BATTERY FORD FIESTA 2020 2021 48V 8AH LX7A-10B759-AD 2495700 BOSCH | eBay

Also, how do you intend charging the battery?
 

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Discussion Starter · #3 ·
What sort of losses are we talking about here? like if it was in the boot for example.

duty cycle ive no idea what that is. I know what it means though I have that on my welders. How would i find out? Idont think its going to be easy to get data sheets

that battery looks a reasonable size any idea on dimensions? might be possible to put it in the engine bay but is 8AH going to be enough? its a 7kw system on the Audi just for the turbo itself.

charging havent got to that yet but there are plenty of options such as running a second alternator. i believe the original charges from the alternator on the car
 

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Can you not get hold of the Audi battery system? Might be the easiest option, mate it to the one the oem uses, and replicate their supply and charge setup.

Seems an interesting project, how much it will however gain you on a 320 is negligible.
 

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What sort of losses are we talking about here? like if it was in the boot for example.

duty cycle ive no idea what that is. I know what it means though I have that on my welders. How would i find out? Idont think its going to be easy to get data sheets

that battery looks a reasonable size any idea on dimensions? might be possible to put it in the engine bay but is 8AH going to be enough? its a 7kw system on the Audi just for the turbo itself.

charging havent got to that yet but there are plenty of options such as running a second alternator. i believe the original charges from the alternator on the car
You will get a couple of minutes max from an 8Ah battery so realistically, enough for a few 'boosts'.
How are you going to recharge the battery? You'd need a DC-DC converter and electronics to control it.

Also, a sudden surge in torque will probably unstick the rear tyres causing possible loss of control.

To be honest you'd get a better result from remap and new maf. You'll need to up the fuel anyway otherwise all that will happen with the extra air, is a big flat spot and serious juddering.

Don't expect a nice smooth transition from the 'boost' to the main turbo either.

What are you actually trying to achieve? Do you feel your 320d is flat at low rpm? if so, change the maf.

Honestly this is the most mad idea I have ever heard of as a diesel tuning mod.

What do you think the clutch and gearbox will think of the sudden boost in torque?
 

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I bought a electric supercharger its from a Audi SQ7 4.0 tdi for those who want to know. the unit is made by valeo part number 057145601D /F

im going to run it on a bmw 320d E90 2006 but ill be keeping the original turbocharger as well this one will just be for initial boost so it will be bursts of power not constant and i believe the amps calculated out at 146a. correct me if im wrong.
How will this work?

If you compress air into the intake of the existing turbo, it will foul up its/the engine's calibration mapping, and difficult to believe you won't run immediately into problems.

If you compress into the manifold, the existing turbo will either push air out via this 'new' turbo, or vice versa.

There is a reason why few cars have used twin turbo setups, and it's because it is a right royal PITA to design for from scratch, let alone trying to monkey an old blower onto something else.
 

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How will this work?

If you compress air into the intake of the existing turbo, it will foul up its/the engine's calibration mapping, and difficult to believe you won't run immediately into problems.

If you compress into the manifold, the existing turbo will either push air out via this 'new' turbo, or vice versa.

There is a reason why few cars have used twin turbo setups, and it's because it is a right royal PITA to design for from scratch, let alone trying to monkey an old blower onto something else.
Not an expert but i always believed Turbo's worked on exhaust gases via exhaust manifold (get exhaust gases out quicker, maker more power) , and Superchargers worked on getting air into the car engine quicker by pushing it into the intake manifold, to make more power.

I have know of several specialist cars over the years that were both Supercharged and Turbocharged at the same time.
 

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Not an expert but i always believed Turbo's worked on exhaust gases via exhaust manifold (get exhaust gases out quicker, maker more power) , and Superchargers worked on getting air into the car engine quicker by pushing it into the intake manifold, to make more power.

I have know of several specialist cars over the years that were both Supercharged and Turbocharged at the same time.
Wrong. Both work by forcing more air in. The turbo is driven by waste energy in the exhaust and the supercharger is driven by the engine.
The supercharger can work from lower rpm and doesn't tend to produce the unavoidable lag that turbo's suffer from.

Because the turbo relies on waste energy, the engine has to be producing some - it's a chicken and egg situation, before it will speed up and produce boost, hence the lag. A turbo actually impedes exhaust flow, which is another reason why doubling the pressure does not give double the bhp.

It's quite easy to envisage what happens with forced induction. Without it, the 1bar of atmospheric pressure is all there is to push air in, add 1bar of boost, then in thoery you can double the airflow and so on. Of course in practice there are losses so doubling the boost doesn't double the power, even if there was enough fuel being injected.
 

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Not an expert but i always believed Turbo's worked on exhaust gases via exhaust manifold (get exhaust gases out quicker, maker more power)
Fortunately I am an expert and can help out here. The turbo slows exhaust and absorbs power (which is mechanical power immediately transferred to the compressor side of the turbo).

The common addition of turbos also permits lesser sound absorption in the exhaust system as the exhaust flow is smoothed out better than if there was no turbo.

The other feature that the OP will struggle with is the intercooler. As the intake gases are compressed (more oxygen in than without it, thus more fuel can be burned) those intake gases get hotter, if left 'hot' then back to square one as less 'mass' can be pushed into the cylinders and also not so effective combustion. So best to cool down the intake charge of air as much as possible after compression.

Adding further supercharging, randomly, will upset the intake charge temperatures.
 

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duty cycle ive no idea what that is. I know what it means though I have that on my welders. How would i find out? Idont think its going to be easy to get data sheets
Given that this is your install you can make the numbers up. By duty cycle I mean how often is it going to operate and for how long each time. For example if it is just to get you off the line from idle until the engine reaches max boost you are probably looking at around 10 seconds at most. In that case you are unlikely to need to use it again for at least another 30 seconds and for say a maximum of 10 times in a row. Anything else would be after a suitable cool down/recharge period. If those figures are correct you are using 7kW x 10 seconds x 10 times = 700,000 Joules which is about 200Wh or 0.2kWh. So that's in the capacity of the battery suggested earlier.
What's not possible is to run the electric turbo for more than twice that - in other words for more than 200 seconds continuously. But why would you? The standard turbo is for that, not an electric powered one. Even if you are into running 0-100 times it will be over in less than 20 seconds in a standard car, and it takes time to slow down to do it again.
I'd be interested to know how you intend to control it. Have you an ECU for it or are you using simple pressure switches?
 

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Don't listen to the nay-sayers on this. I did something similar using a built up electric powered Garrett turbo for Escort Cosworths. It worked in a crude way but was much heavier and complex than anti-lag that was developed at the same time and didn't require homologation.
 
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Don't listen to the nay-sayers on this. I did something similar using a built up electric powered Garrett turbo for Escort Cosworths. It worked in a crude way but was much heavier and complex than anti-lag that was developed at the same time and didn't require homologation.
The op has no electronics knowledge if he doesn't know what duty cycle is and hasn't said how he plans to recharge the battery.
Unless he has someone lined who does have the relevant knowledge and skills he has a lot of issues to overcome.
He's also not said how he will plumb in the electric turbo and how he will control the changeover valve.
 

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Don't listen to the nay-sayers on this. I did something similar using a built up electric powered Garrett turbo for Escort Cosworths. It worked in a crude way but was much heavier and complex than anti-lag that was developed at the same time and didn't require homologation.
Let the OP answer some of the fundamentally simple questions we've asked first. This sounds to me like it is going nowhere very quickly.

How is he even going to power this turbo? It is not going to be a simple DC power supply or such. How will he even PWM his 48V battery?
 

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Discussion Starter · #15 ·
Not an expert but i always believed Turbo's worked on exhaust gases via exhaust manifold (get exhaust gases out quicker, maker more power) , and Superchargers worked on getting air into the car engine quicker by pushing it into the intake manifold, to make more power.

I have know of several specialist cars over the years that were both Supercharged and Turbocharged at the same time.
yeah thats right
 

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Discussion Starter · #16 ·
Given that this is your install you can make the numbers up. By duty cycle I mean how often is it going to operate and for how long each time. For example if it is just to get you off the line from idle until the engine reaches max boost you are probably looking at around 10 seconds at most. In that case you are unlikely to need to use it again for at least another 30 seconds and for say a maximum of 10 times in a row. Anything else would be after a suitable cool down/recharge period. If those figures are correct you are using 7kW x 10 seconds x 10 times = 700,000 Joules which is about 200Wh or 0.2kWh. So that's in the capacity of the battery suggested earlier.
What's not possible is to run the electric turbo for more than twice that - in other words for more than 200 seconds continuously. But why would you? The standard turbo is for that, not an electric powered one. Even if you are into running 0-100 times it will be over in less than 20 seconds in a standard car, and it takes time to slow down to do it again.
I'd be interested to know how you intend to control it. Have you an ECU for it or are you using simple pressure switches?

it will be from idle until either turbo starts to spool up so maybe 700 to 1500 rpm but only testing will tell because it depends how quick the electric charger can get the revs up for the other turbo to then take over. ive a feeling it may not be for as long as you would think because in theory if the electric turbocharger is pushing in a decent amount it can speed up the time to get to where its cut off.

i dont know if youve seen it but there are many electric supercharger video's on youtube titles $1500 turbo $2500 turbo $4500 turbo. all have 1 thing in common they are running from 12 volts and in tests they are only producing a max of about 5 psi which is pretty useless for as diesel as they average 20 psi on most diesels in stock form. so the ney sayers will have probably seen these video's but there is a guy on youtube runs a 6 min video and he talks about thissystem in the audi thats where i got the 7kw from its supposed to be the rating of the turbocharger.

control wise thats probably going to be my brothers department he's a tuner he's done custom builds and aftermarket ecu's etc so he knows all that stuff.
 

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Discussion Starter · #17 ·
The op has no electronics knowledge if he doesn't know what duty cycle is and hasn't said how he plans to recharge the battery.
Unless he has someone lined who does have the relevant knowledge and skills he has a lot of issues to overcome.
He's also not said how he will plumb in the electric turbo and how he will control the changeover valve.
i didnt say i didnt know what duty cycle means, i just dont know the duty cycle of this turbocharger.


plumbing in etc is not something im concerned about right now, what im concerned about right now is doing a lot of research getting some opinions from others and then deciding what the next thing to buy will be. for wiring and electronics thats my brothers department he is a tuner, engine builder and he works with aftermarket ecu's etc.
 

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i didnt say i didnt know what duty cycle means, i just dont know the duty cycle of this turbocharger.


plumbing in etc is not something im concerned about right now, what im concerned about right now is doing a lot of research getting some opinions from others and then deciding what the next thing to buy will be. for wiring and electronics thats my brothers department he is a tuner, engine builder and he works with aftermarket ecu's etc.
Fair enough. You obviously like a challenge!
 

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Discussion Starter · #19 ·
Let the OP answer some of the fundamentally simple questions we've asked first. This sounds to me like it is going nowhere very quickly.

How is he even going to power this turbo? It is not going to be a simple DC power supply or such. How will he even PWM his 48V battery?
you are exactly right its going nowhere quickliy that is true. this is still in the research stage and process of gathering parts so there is a lot of legwork to do. at the moment im looking at batteries seems i can buy the audi battery but there may be a better solution that is easier to integrate.

but i would welcome information about charging because if i do buy a battery i will want to keep it healthy until its actually going to be used.
 
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