Topic: Turbocharging: theory versus reality

[huota]

Another angle to the topic; Volvo used to make five specifications of the same I5 base engine with slightly varying bores and with or without turbo. Below are the euro specs from the least to most powerful.

2435cm2 125hp/220Nm: city/highway 12.2/6.8 l/100km
2435cm2 170hp/225Nm: 12.3/6.8
2521cm2 210hp/320Nm: 12.9/6.9
2401cm2 260hp/350Nm: 12.7/7.3
2521cm2 300hp/400Nm: 14.5/8.2

Note that the last one is an AWD.

Seems like the turbo's get more oomph for little penalty in mileage...

[vdk]

It would be interesting to see how the 2.0FSI and the 2.0TFSI compare... I'm struggling to find some #s...

[huota]

It would be interesting to see how the 2.0FSI and the 2.0TFSI compare... I'm struggling to find some #s...

From volkswagen.de, the below figures are for the Golf:

FSI 2.0: 150hp, 200Nm, 8.8s, city/highway 11.0/6.3
TFSI 2.0 (aka GTI): 200hp, 280Nm, 7.2s, 11.0/6.2
TSI 1.4: 140hp, 220Nm, 8.8s, 9.5/5.7
TSI 1.4: 170hp, 240Nm, 7.9s, 9.9/5.8

The 2.0 FSI is pretty much redundant nowadays. Apparently, the Mk VI Golf will come with the 122hp and 160hp 1.4 TSI's as well as 1.4 and 1.6 NA engines.

[vdk]

Ich sprache deutsche somewhat... Danke fur die nummern !

It seems that manufacturers use turbos to improve performance rather than fuel economy...
Looks like all VW gas engines are turbo nowadays in Europe...

[99 Silver]

Here are my belated thoughts on this discussion.

I think the best potential in using turbos to reduce fuel consumption is that you can move the same car with a smaller displacement engine with similar performance to the larger engine.  There would be weight savings which would help improve city mileage and on the highway you would use less fuel if you stay off boost.

I was surprised at how much complexity a turbo added when I started to really get into understanding and improving the power in my Miata.  There is a lot of additional plumbing, an intercooler, additional oil cooling capacity, bigger radiator, blowoff valve, catch can and boost controller. Most of this stuff is fairly light, but it must be costly to manufacture.

A turbo could be maximized for fuel efficiency by reducing the amount of time you are under boost.  I drove a CX7 and it seemed to be under boost constantly even under light acceleration.  Perhaps that explains it's higher than expected fuel consumption. My 04 Miata gets slightly better mileage than my 99 did because boost isn't a factor until just under 3k rpm.  I have changed the intake, exhaust, boost controller, and blowoff valve to gain an extra 50 whp, but the fuel economy is down because boost comes on much earlier (2k rpm +/-) and it is on boost quite a bit more even under light throttle.

It will be interesting how Ford handles turbos.

[Wolfe]

The engine tuning is the key.

We're so used to thinking of turbocharging just to increase the power output of an engine that turbos are rarely though of in any other way.

It will be interesting how Ford handles turbos.

I've posted this link before but it's right on topic again so: http://autospeed.com/cms/A_109931/article.html

[ktm525]

The engine tuning is the key.

We're so used to thinking of turbocharging just to increase the power output of an engine that turbos are rarely though of in any other way.

It will be interesting how Ford handles turbos.

I've posted this link before but it's right on topic again so: http://autospeed.com/cms/A_109931/article.html

Good link. I would think Ford would just download everything Volvo has learned from turbos. Perhaps that is why Ford decided to keep them around, to suck their knowledge dry!

[huota]

I've posted this link before but it's right on topic again so: http://autospeed.com/cms/A_109931/article.html

Thanks for the link, it's a very good summary of what I think will be the future application of turbocharging. Except that the future is already here.

[The Mighty Duck]

Here are my belated thoughts on this discussion.

I think the best potential in using turbos to reduce fuel consumption is that you can move the same car with a smaller displacement engine with similar performance to the larger engine.  There would be weight savings which would help improve city mileage and on the highway you would use less fuel if you stay off boost.

Exactly.  It's like Chrysler Multiple Cylinder Displacement idea...  when you don't need lots of power (say at highway speeds) the engine spins slower and stays off boost.  But when you hammer the throttle, the boost comes on and you get the power you need.  Much better than running a V6 or V8 where all the cylinders are always firing...  instead you get I4-like economy with V6 or even V8-like power when it's needed...

[mmret]

From the perspective of "extra oomph when you need, more efficiency when you don't" perspective, if you're talking about VCM or MDS or whatever they want to call it you still have to drive the extra weight and friction of those idle cylinders. Not so with a turbo...

Also, why exactly do American manufacturers shy away from turbos so much relative to their euro counterparts? Crappier gasoline and public aversion to buying anything other than good ol' 87?

[Mitlov]

From the perspective of "extra oomph when you need, more efficiency when you don't" perspective, if you're talking about VCM or MDS or whatever they want to call it you still have to drive the extra weight and friction of those idle cylinders. Not so with a turbo...

Also, why exactly do American manufacturers shy away from turbos so much relative to their euro counterparts? Crappier gasoline and public aversion to buying anything other than good ol' 87?

I think it has more to do with the fact that (1) the idea of turbos for economy instead of for performance is relatively new (to all regions), and (2) when it comes to performance cars, American consumers prefer V8s, naturally-aspirated or supercharged.  As for why that is?  A combination of history and the straighter roads we have here.  A Challenger may be the wrong tool for the Isle of Mann, but a Cooper S is equally unsuited anything you'll find in Nebraska or Texas. 

[safristi]

 which German car has the Turbo vanes "expandable" maybe re_routed thru a short spin cycle! and a long-er spin cycle...via controlled valve flaps.... BMW!!?...to achieve different power outputs.........

[ktm525]

which German car has the Turbo vanes "expandable" maybe re_routed thru a short spin cycle! and a long-er spin cycle...via controlled valve flaps.... BMW!!?...to achieve different power outputs.........

Variable vane turbos are veeeeery expensive, even for the Krauts. Cheaper to have two turbos with different missions in life (low RPM and high RPM)

[safristi]

OK suck the life outta ME if ya MUST..............   ME HAVE SUPERCHARGER..........me slower off tha MARK.........   Me so so VANE!!!! i wear Carley Simons KNICKERS...........

[The Mighty Duck]

From the perspective of "extra oomph when you need, more efficiency when you don't" perspective, if you're talking about VCM or MDS or whatever they want to call it you still have to drive the extra weight and friction of those idle cylinders. Not so with a turbo...

Also, why exactly do American manufacturers shy away from turbos so much relative to their euro counterparts? Crappier gasoline and public aversion to buying anything other than good ol' 87?

I agree - I would rather have a turbo than a V8 with MDS.  But they acheive similar results. 

As for Americans...  "there's no replacement for displacement" is a very popular mentality, no? 

[ktm525]

From the perspective of "extra oomph when you need, more efficiency when you don't" perspective, if you're talking about VCM or MDS or whatever they want to call it you still have to drive the extra weight and friction of those idle cylinders. Not so with a turbo...

Also, why exactly do American manufacturers shy away from turbos so much relative to their euro counterparts? Crappier gasoline and public aversion to buying anything other than good ol' 87?

I agree - I would rather have a turbo than a V8 with MDS.  But they acheive similar results. 

As for Americans...  "there's no replacement for displacement" is a very popular mentality, no? 

Seems to work for the Z06...

[Loudpedal]

From the perspective of "extra oomph when you need, more efficiency when you don't" perspective, if you're talking about VCM or MDS or whatever they want to call it you still have to drive the extra weight and friction of those idle cylinders. Not so with a turbo...

Also, why exactly do American manufacturers shy away from turbos so much relative to their euro counterparts? Crappier gasoline and public aversion to buying anything other than good ol' 87?

I agree - I would rather have a turbo than a V8 with MDS.  But they acheive similar results. 

As for Americans...  "there's no replacement for displacement" is a very popular mentality, no? 

I once read, "...there's no replacement for displacement...but volumetric efficiency comes close...".

The funniest engine T-shirt I ever read was "injection is nice, but I'd rather be blown..." 

Wolfe: great engine link 

[safristi]

how much does the Turbo cost for the extra oomph..in terms not just of  UP_FRONT parts ,but in USE......how much does the extra oomph take outta the engines life. 1 ..2 ..3 years?....(2)are SUPERCHARGERS dead as a way to achieve more poke from smaller displacement...My Millenia(2.3L engine) is starting to puff out a lil blue smoke on morning startup..i believe it's seal related (Supercharger seals or elswhere..i ain't sure) any ideas!!!?.....I don't believe in the "FREE LUNCH THEORY" U pay fer POWER..............one way or 'tother

  Maybe these lil quick BOOST electric "thingies" will be the new SUPER_TURBO_WAY to GO.....Fashter and FASHTER....