IDEA : Asymmetric Turbocharging

[jagunx51]

I dont know whether this topic ever been discussed before... I've been search in the forum for 'asymmetric turbocharging', and find nothing

At first I want to write it on GPU thread & Alternative PU thread, but I think it is better to stand alone thread because it's not just about PU, but I more concerned about the noise



I thought it was my idea, but then I found this site

http://www.pistonheads.com/gassing/topi ... 6&t=287344

A bit different than Saab 9-5 3.0t asymmetric turbocharging system, my idea is using the opposite cylinders right in front of the gearbox to fed the turbocharger

The point is using some cylinders to fed the Turbo and the others are to produce noise. Off course it need to increase the rpm limiter, perhaps 18K (?)
So, there will be 5 exhaust pipes on the back, 2 are for wastegates

Is it possible to apply this on 2019 F1 car? I think it wont need a lot of development. Perhaps only some considerations about mechanical and thermal balances

Im not an engine guru, so I might be mistaken

*EDIT: some quote from pistonheads.com

" In an 'asymmetric' turbo installation, all cylinders are force fed through a single intake/plenum - but the 'hot' side of the turbo is driven by the exhaust gases of only one cylinder bank. This was used in the Saab 9-5 3.0t to provide a modest, but useful performance boost in the low/midrange rpm band with as simple a configuration as possible. Not only you can simply hang the turbo on the end of one exhaust manifold as per an in-line engine (in fact, in the Saab's case the exhaust turbine housing was integrated into the manifold) but as you're only using the exhaust gases of three cylinders to pump more air into six, the resulting boost pressure was low enough to remain unregulated - there's no wastegate on this one. "

Some links :

https://forums.anandtech.com/threads/wh ... v6.788612/

http://www.cardomain.com/ride/2962382/2001-saab-9-5/

http://raquettelaker2.blogspot.co.id/20 ... mages.html

[Shooty81]

To use whatever to create noise.

Seems people still belief noise is the only thing that is important in motorracing.

Then why not put a proper sound system into the car or in front of the spectators? We have DRS, we have mandatory pitstops. Why not add some artifical sound?

I always thought noise is an unavoidable but unwanted side effect of going fast.

I was at the racetrack. And I like the sound of the V6 engines in real life. Much more than the old V8s or V10s. Those were so loud, it was hurting.
Plus the new cars sound like cars. And not like a too loud sewing machine.


Maybe the problem of F1 is that fans are getting old. They live in the past.

[Shooty81]

Sorry for the OT post before. Now back to the technical aspect:

You boost one cylinder bank with the compressor without using the exhaust gases after combustion. That means a lot of losses. But also a lot of noise (which might be a good thing in some peoples POV).

For the efficiency (and therefore performance in a fuel-flow limited formula) you rather try to have the pressure evenly distributed and use as much of the energy as possible.


You can improve the situation by using different valve timing (eg. atkinson cycle on one bank) for example.

[jagunx51]

Sorry for the OT post before. Now back to the technical aspect:

You boost one cylinder bank with the compressor without using the exhaust gases after combustion. That means a lot of losses. But also a lot of noise (which might be a good thing in some peoples POV).

For the efficiency (and therefore performance in a fuel-flow limited formula) you rather try to have the pressure evenly distributed and use as much of the energy as possible.


You can improve the situation by using different valve timing (eg. atkinson cycle on one bank) for example.

refer to the 2nd pic (F1 concept), two (or perhaps four) cylinders are feeding the turbo unit, but the cmpressor supplying air for all cyclinders .....similar to what SAAB did, but different execution

[DiogoBrand]

That's an interesting idea.
Trouble is: since they are running a lot lower rpm than with the V8's, even if you make the engines louder, they're still not gonna sound as good. And as has been mentioned, you're gonna take cylinders with forced induction and throw the exhaust gases at the bin, which not only wastes a lot of energy, but I think would sound a lot like a supercharged engine, so as I said, even though it would be louder, the sound wouldn't necessarily be pleasant like it was before.
To me this subject is just a losing battle. Motorsport is moving towards efficiency, and loud engines are very unefficient.
And no matter what you do, F1 fans live in the past. Last year they complained because of disposable tyres, now they complain that the more durable tyres are boring. They asked for powerful turbo engines back, now they want loud NA engines. I can guarantee that once they ban DRS, people will complain that DRS was exciting. So there's no point trying to please people that can't be pleased.

[jagunx51]

That's an interesting idea.
Trouble is: since they are running a lot lower rpm than with the V8's, even if you make the engines louder, they're still not gonna sound as good. And as has been mentioned, you're gonna take cylinders with forced induction and throw the exhaust gases at the bin, which not only wastes a lot of energy, but I think would sound a lot like a supercharged engine, so as I said, even though it would be louder, the sound wouldn't necessarily be pleasant like it was before.
To me this subject is just a losing battle. Motorsport is moving towards efficiency, and loud engines are very unefficient.
And no matter what you do, F1 fans live in the past. Last year they complained because of disposable tyres, now they complain that the more durable tyres are boring. They asked for powerful turbo engines back, now they want loud NA engines. I can guarantee that once they ban DRS, people will complain that DRS was exciting. So there's no point trying to please people that can't be pleased.

Like I said before, the limiter might be set up to 18K

So, 2 cylinders working for the turbo, while four others is 'normally aspirated' ....there will be 5 exhaust pipes, 2 from the 'NA cyclinders', 2 from wastegates, and single pipe from turbocharger .... then we will have two kind of sounds

Me myself cannot imagine what it will sound like ....perhaps like listening music on Ipod in the soccer stadium, with only earplug on the left ear

If they could change the regulation, we could have a blown diffuser from the 'normally-aspirated' cyclinders

[godlameroso]

To use whatever to create noise.

Seems people still belief noise is the only thing that is important in motorracing.

Then why not put a proper sound system into the car or in front of the spectators? We have DRS, we have mandatory pitstops. Why not add some artifical sound?

I always thought noise is an unavoidable but unwanted side effect of going fast.

I was at the racetrack. And I like the sound of the V6 engines in real life. Much more than the old V8s or V10s. Those were so loud, it was hurting.
Plus the new cars sound like cars. And not like a too loud sewing machine.


Maybe the problem of F1 is that fans are getting old. They live in the past.

If your engine is good, it should make good sounds, much like a musical instrument.

[bill shoe]

In the heyday of CART, the Toyota and/or Honda engines were set up like this for oval qualifying. They sent one bank of the v8 exhaust straight out the back, and the other bank went thru the turbo and/or wastegate. Apparently there was a small gain in peak power, but at the expense of more turbo lag.

Current F1 power units have the MGU-H which can spool up the turbo, so this is an effective way to address the turbo lag. I don't understand exactly where the power gain came from, meaning I couldn't sketch a PV diagram that showed the advantage. Interesting subject to consider.

[Pierce89]

Maybe the problem of F1 is that fans are getting old. They live in the past.

Of course this is the problem. My generation was the last to truly get into f1 and I'm now in my mid 30s. God that last bit was painful to write.

[Bence]

In the heyday of CART, the Toyota and/or Honda engines were set up like this for oval qualifying. They sent one bank of the v8 exhaust straight out the back, and the other bank went thru the turbo and/or wastegate. Apparently there was a small gain in peak power, but at the expense of more turbo lag.

Yup, the old Toyota Indy V8 SST (Single Side Turbo)...

It was used exclusively on ovals where the lag was negligible and it was loud as hell. That time the Honda was the quietest, smoothest engine; it was like there were no moving parts in it, just some kind of performance generating rich liquid. On the straights they were stealthy as electric skateboards. The Ford had a bit more texture and sound, but the SST beasts sounded like your entire lungs wanted to rip out of your ribcage...

If you were standing on the pitlane at the side of an idling Toyota, you were not able to hear the Honda-powered cars on the straight @WOT/Vmax.

[dans79]

Current F1 power units have the MGU-H which can spool up the turbo, so this is an effective way to address the turbo lag. I don't understand exactly where the power gain came from, meaning I couldn't sketch a PV diagram that showed the advantage.

I'd assume it was because half the cylinders had minimal back pressure, so less energy was spent on getting the exhaust out of those cylinders.

[Pierce89]

Because of the all caps I keep reading this thread as: IKEA: Asymmetric turbocharging. I also keep picturing a mechanic putting the whole PU together with a single hex head .

[3jawchuck]

Because of the all caps I keep reading this thread as: IKEA: Asymmetric turbocharging. I also keep picturing a mechanic putting the whole PU together with a single hex head .

That would at least make the McLaren mechanics' jobs easier.

[Moose]

If your engine is good, it should make good sounds, much like a musical instrument.

Quite the reverse actually. A perfect engine will be completely silent, and run at the ambient air temperature.

Energy put into making sound or heat is wasted energy.

That's why modern F1 engines are so quiet - they're better, more efficient engines that waste less energy on these things.

[Shooty81]

If your engine is good, it should make good sounds, much like a musical instrument.

Quite the reverse actually. A perfect engine will be completely silent, and run at the ambient air temperature.

Energy put into making sound or heat is wasted energy.

That's why modern F1 engines are so quiet - they're better, more efficient engines that waste less energy on these things.

Small misunderstanding again: if it is good, it will make good (not so loud) sound haha