Topic: Test Drive: 2010 Volkswagen Golf 2.5L

[vdk]

It's an engine suited to the NA market. Relatively large displacement, lazy, not very powerful but torquey down low, cheap and unpretentious.

If an extra 20hp would make that engine "pretentious" I'd be willing to live with the label.

Jaeger

If they add DI like Hyundai yes they could get 20hp. The 2009 non-DI 2.4L Hyundai had made 175hp vs 198hp with DI.

There's also a ECU reflash if you want. Runs on 91, 180hp 200tq. VW could've done that, but people would've bitched cause it runs on premium. Can't have your cake and eat it too.


What you're doing here is comparing Hyundai's brand new DI mill with others that have been around for some time.

[tpl]

That 2.5 is the only NA certified engine that runs on regular gas I think.   There are undoubtedly versions of old 1.8, 1.6 and 2.0 that run on tractor fuel elsewhere in the world but not NA emission engines.

[vdk]

The current Sentra Spec V makes 200hp from 2.5l.  The mid-level Accord engine makes 190hp from 2.4l.  The basest of base model Hyundai Sonata makes 190hp from 2.4l.  All 4 cylinders.  All the same or less displacement than VW's 5 cylinder. 

It's not about market segment or market branding as "performance" or "mainstream" - it's simply an observation about volumetric efficiency.  Making more power from less displacement is not a bad thing, it's a good thing.  As I have said, 170 from 2.5l is not bad, it doesn't suck and it certainly doesn't offend.  But neither does it impress.  If Hyundai sticks that 2.4l 4-banger into a compact sedan, you think they'll detune it to 170 because that's on par with the market segment?  I don't.

Jaeger

PS - VWs are wonderfully wonderful and only surpassed by their exceptionally wonderful drivers.

You like to pick your cars don't you?

Sentra SE-R : 177hp
Base Accord: 177hp

What about those? By your standards they're low on power.

[HeliDriver]

The current Sentra Spec V makes 200hp from 2.5l.  The mid-level Accord engine makes 190hp from 2.4l.  The basest of base model Hyundai Sonata makes 190hp from 2.4l.  All 4 cylinders.  All the same or less displacement than VW's 5 cylinder. 

All of those engines use sophisticated variable valve timing systems. AFAIK, the 2.5L in the VW doesn't.

And, I would guess those other engines make their peak power higher in the rev range than does the VW 2.5L. Probably higher than your average 2.5L Golf buyer would ever rev the car anyway.

[Jaeger]

What about those? By your standards they're low on power.

Yes, in response to examples of 2.5l motors making roughly the same as the VW mill, I was "picking" examples of others which make more with less.  I guess you like to "pick your cars" too. 

And no, I'm not saying that those making 170ish hp are "low on power" (again with you VW reactionaries putting words in my mouth) - just not particularly impressive - as I have said of the VW.  Out of 2.5 liters, I'd like to see 190-200 horsepower in a contemporary engine.  Put another way, 170 is a pretty "dated" output for 2.5l.  The bar has been raised.

Jaeger

PS - Your VW is wonderful and you are wonderful for driving one.

[Jaeger]

What about the extra cylinder?  My SE-R gets 177hp from a 2.5L four...

I understand that everyone in the segment is around that 170 mark with big fours, and VW is right in the mix...  2.5L is 2.5L, right, but the VW has an extra cylinder and around the same, if not a little less, hp...

I think displacement has a lot more to do with power output than number of cylinders does.
And for what it's worth, Volvo's naturally-aspirated 2.4L inline-five puts out power similar to VW's.  Just a tad less than the VW, I think.

I mostly agree - displacement is more important, but cylinder count is not irrelevant, particularly when it comes to expectations.  Case in point - the new "baby" G25 uses a 2.5 liter V6 and is reported to make 210hp.  Nobody jumps up and down about that being so very much power even though the displacement is "only" 2.5l.  Why?  Because it's a V6 and we expect at least that kind of power.  If they managed 40 hp less - like the 5 cylinder VW of the same displacement - they'd be a laughing stock.

Jaeger

[Mitlov]

I mostly agree - displacement is more important, but cylinder count is not irrelevant, particularly when it comes to expectations.  Case in point - the new "baby" G25 uses a 2.5 liter V6 and is reported to make 210hp.  Nobody jumps up and down about that being so very much power even though the displacement is "only" 2.5l.  Why?  Because it's a V6 and we expect at least that kind of power.  If they managed 40 hp less - like the 5 cylinder VW of the same displacement - they'd be a laughing stock.

Jaeger

I expect more from a US$31,000 sport sedan than I do from a US$17,500 mass-market hatchback, don't you?  The 2.5L is a cheap base engine in a cheap car.  Most of the engines you're using as counter-evidence (the Spec V's engine, the Accord EX's engine, and most of all the Infiniti 2.5L V6) are far more expensive applications.

The Sonata engine is the only engine you've offered up for comparison that is comparable in terms of price point as well as displacement to the VW 2.5L, and as vdk mentioned, it's a brand-new engine using DI, something essentially none of its competitors offer yet.  Without DI, it was right where the VW is performance-wise.

[Thinking Out Loud]

What about those? By your standards they're low on power.

Not "low" - just not particularly impressive - as I have said of the VW.  Out of 2.5 liters, I'd like to see 190-200 horsepower.

Jaeger

Well, the SE-R Spec V puts out 200hp from the same 2.5 motor the SE-R has, and makes do with only 177hp - I suppose it is detuned on purpose for differentiation from the Spec V 'cause the CVT should be able to handle it...too bad it only comes with the 6 speed manual cause the wife can't drive stick....

[Jaeger]

I mostly agree - displacement is more important, but cylinder count is not irrelevant, particularly when it comes to expectations.  Case in point - the new "baby" G25 uses a 2.5 liter V6 and is reported to make 210hp.  Nobody jumps up and down about that being so very much power even though the displacement is "only" 2.5l.  Why?  Because it's a V6 and we expect at least that kind of power.  If they managed 40 hp less - like the 5 cylinder VW of the same displacement - they'd be a laughing stock.

Jaeger

I expect more from a US$31,000 sport sedan than I do from a US$17,500 mass-market hatchback, don't you?  The 2.5L is a cheap base engine in a cheap car.  Most of the engines you're using as counter-evidence (the Spec V's engine, the Accord EX's engine, and most of all the Infiniti 2.5L V6) are far more expensive applications.

Well, obviously.  But when you hear 2.5 V6, are your expectations the same as when you hear 2.5 4 pot?  Right or wrong, mine aren't.  

Jaeger

[Mitlov]

Well, obviously.  But when you hear 2.5 V6, are your expectations the same as when you hear 2.5 4 pot?  Right or wrong, mine aren't.  

Jaeger

Perhaps I've been conditioned to not look first to cylinder count because of motorcycles, but no, that's not really where I go.  I worry about its displacement and how it's been tuned, paying only minimal attention to cylinder count.  The tuning of the VW 2.5L (due to price concerns and the intended user) is analogous to the Altima 2.5L, not either the Spec V or the G25. 

As for the rest of the market, maybe a lot of people go there, but we should not celebrate or encourage reasoning about engineering issues that has little or no basis in actual engineering fact.

The rest of the market also thinks RWD is *gasp* dangerous, but that doesn't make it so.

[Jaeger]

Well, obviously.  But when you hear 2.5 V6, are your expectations the same as when you hear 2.5 4 pot?  Right or wrong, mine aren't.  

Jaeger

Perhaps I've been conditioned to not look first to cylinder count because of motorcycles, but no, that's not really where I go.  As for the rest of the market, maybe a lot of people go there, but we should not celebrate or encourage reasoning about engineering issues that has little or no basis in actual engineering fact.

The rest of the market also thinks RWD is *gasp* dangerous, but that doesn't make it so.

Well, I'm not an engineer, so while it seems to make sense to me that displacement is MORE important than cylinder count in a normally aspirated engine,  I'm not in a position to say that cylinder count is irrelevant to power output.  Are you?  If anyone does know, I'd be interested in hearing the answer because I really don't know.

I remember when I had my '91 4-pot  240SX, a couple buddies each had the competitor Ford and Mazda offerings, which used  a compact V6 of almost the same displacement.  Theirs made more power.

Jaeger

[footlong58]

Just for giggles a 2.4L v8 f1 engine puts out about 800hp...

[Arctic_White]

The Honda 2.0L makes 197 horsepower, but you have to rev it to nearly 9000 rpm to get that because it doesn't have any frakking torque!  139 ft-lbs at 6100 rpm, to be exact.  It'd be a TERRIBLE mass-market engine.  There's a reason it's restricted to the Civic Si and not used in other cars. 

I've never felt that Si has low torque, as the car takes good advantage of its amazing gear ratios. 

Besides, torque is only needed to get you off the line.  Once the car is moving, the Si is actually very quick!

Yes, you won't be winning any drag races with the Si, but that's not its purpose.  ;-)


Getting back to the Golf, it's an amazing looking car.  I love its exterior! 

[vdk]

Yes, in response to examples of 2.5l motors making roughly the same as the VW mill, I was "picking" examples of others which make more with less.  I guess you like to "pick your cars" too. 

Thank you!

Out of 2.5 liters, I'd like to see 190-200 horsepower in a contemporary engine.  Put another way, 170 is a pretty "dated" output for 2.5l.  The bar has been raised.

But this 'dated' output of 170hp per 2.5L is so common today. Nissan, VW, Honda, Mazda, Volvo, Suzuki, GM, Ford all have similar sized engines with HP outputs of 170-180hp. Only the Hyundai makes almost 200, and the 2.4L VTEC in the TSX/Accord. It is hardly non-competitive in the market. You can and complain about VW, but this ain't it. 

PS - Your VW is wonderful and you are wonderful for driving one.

Call me

[Jaeger]

Just for giggles a 2.4L v8 f1 engine puts out about 800hp...

 

[Mitlov]

Well, obviously.  But when you hear 2.5 V6, are your expectations the same as when you hear 2.5 4 pot?  Right or wrong, mine aren't.  

Jaeger

Perhaps I've been conditioned to not look first to cylinder count because of motorcycles, but no, that's not really where I go.  As for the rest of the market, maybe a lot of people go there, but we should not celebrate or encourage reasoning about engineering issues that has little or no basis in actual engineering fact.

The rest of the market also thinks RWD is *gasp* dangerous, but that doesn't make it so.

Well, I'm not an engineer, so while it seems to make sense to me that displacement is MORE important than cylinder count in a normally aspirated engine,  I'm not in a position to say that cylinder count is irrelevant to power output.  Are you?  If anyone does know, I'd be interested in hearing the answer because I really don't know.

I remember when I had my '91 4-pot  240SX, a couple buddies each had the competitor Ford and Mazda offerings, which used  a compact V6 of almost the same displacement.  Theirs made more power.

Jaeger

Good timing.  I just got my latest issue of Cycle World which had a liter-bike shootout.  Nine sportbikes, all 1000ccs.  Two V-twins (Ducati 1198S Corse and KTM RC8R), one V-four (Aprilia RSV4 Factory), and six inline-fours (BMW S1000RR, Honda CBR1000RR, Kawasaki ZX-6R, MV Agusta F4, Suzuki GSX-R1000, and Yamaha YZF-R1). 

There was not a significant difference in absolute power output.  The fours ranged from 160.3 hp (Suzuki) to 191.0 hp (BMW), with most coming in in the low 170s.  The V-twins came in at 165.3 (Ducati) and 164.7 (KTM).  So on average, 1000cc four-cylinders made about 5% more peak horsepower than the 1000cc twins.

There WAS a significant difference in where they make the power.  The Ducati and the KTM both made their peak torque at 8,000 rpm; the fours all made their peak torque around 10,000 rpm.

Four cylinders can rev a bit higher than twins of the same displacement because the smaller cylinders result in lower piston speeds.  So you get higher redlines on four-cylinders, allowing you to get a bit more power out of the top end, but still, not a huge difference between two engines with similar tuning but different cylinder numbers.  I don't know why fewer cylinders gives you better torque, though.

None of these maximum-piston-speed considerations really factor in when we're comparing base engines in the Golf and Altima, though.  They're just not in a high enough state of tune where it matters.  I'm not sure why exactly VW went with a five-cylinder instead of a four-cylinder...maybe just to "be different" or something.

[HeliDriver]

... I'm not sure why exactly VW went with a five-cylinder instead of a four-cylinder...maybe just to "be different" or something.

Didn't they cut the Gallardo V-10 in half to make the Golf 2.5L? Or maybe they stuck two of the Golf fives together to make the Gallardo V-10?

Okay, I'm joking... but only kind of.

I think I read somewhere that the two engines are (however slightly) related. Maybe it was big-picture corporate efficiencies that led to VAG's decision to go with a 2.5L five in the Golf. 

[vdk]

... I'm not sure why exactly VW went with a five-cylinder instead of a four-cylinder...maybe just to "be different" or something.

Didn't they cut the Gallardo V-10 in half to make the Golf 2.5L? Or maybe they stuck two of the Golf fives together to make the Gallardo V-10?

Okay, I'm joking... but only kind of.

I think I read somewhere that the two engines are (however slightly) related. Maybe it was big-picture corporate efficiencies that led to VAG's decision to go with a 2.5L five in the Golf. 

They share something. I forgot what exactly, but I think it was the heads.

VWs used straight 5s before, even today in Europe they have a VR5 which is essentially an I5 of similar displacement to the one we get in NA.

[JSCC]

... I'm not sure why exactly VW went with a five-cylinder instead of a four-cylinder...maybe just to "be different" or something.

Didn't they cut the Gallardo V-10 in half to make the Golf 2.5L? Or maybe they stuck two of the Golf fives together to make the Gallardo V-10?

Okay, I'm joking... but only kind of.

I think I read somewhere that the two engines are (however slightly) related. Maybe it was big-picture corporate efficiencies that led to VAG's decision to go with a 2.5L five in the Golf. 

They share something. I forgot what exactly, but I think it was the heads.

VWs used straight 5s before, even today in Europe they have a VR5 which is essentially an I5 of similar displacement to the one we get in NA.

It is the cylinder head.
http://www.caranddriver.com/reviews/car/05q2/volkswagen_jetta-road_test/tech_highlights_page_3

The Jetta V was launched back in 2005, didn't even notice it's already been 5 years. 

[Jaeger]

Good timing.  I just got my latest issue of Cycle World which had a liter-bike shootout.  Nine sportbikes, all 1000ccs.   Two V-twins (Ducati 1198S Corse and KTM RC8R), one V-four (Aprilia RSV4 Factory), and six inline-fours (BMW S1000RR, Honda CBR1000RR, Kawasaki ZX-6R, MV Agusta F4, Suzuki GSX-R1000, and Yamaha YZF-R1). 

Interesting.

I know squat about bikes, but maybe the fact that these are all "sportbikes" and (I assume) all tuned to get the very most out of their available displacement, then the differences (if any) resulting from number of cylinders in minimized?  Or put another way - in a less maxed-out state out tune (such as one would expect in volume-selling motor vehicle), is it perhaps easier to get more power from an engine with more cylinders but the same displacement?  Again, I don't claim to know. 

It's just my perception that, over time,  2.5l V6s seem to make more power on average than 2.5l 4-pots - but there are lots of variables at play.  Only 0.2l separate a 3.8l V6 from a 4.0l V8 - but I expect the output of the latter to be higher.  That may be an unfounded expectation on my part, but there you go.

Jaeger