Author Topic: Honda's new generation of VTEC turbo engines  (Read 27249 times)

culzean

  • Approved Member
  • *
  • Posts: 8017
  • Country: england
Re: Honda's new generation of VTEC turbo engines
« Reply #15 on: February 28, 2014, 09:34:05 AM »
I would have expected that the turbo would be by-passed under low power conditions such as normal town driving otherwise fuel-saving autostop wouldn't get much opportunity to work.

according to what i have read on the clubjazz forum so far, it is the low down oommph that people want,  so disabling the turbo for urban driving is a bit of a non-starter. Turbo diesels are a different matter because on a diesel compression ratio is everything and a turbo can increase the specific cylinder pressure.

also claimed gains in mpg are not what they seem,  all smoke and mirrors to me (the smoke is what you get when turbo blows,  and the mirrors are what you use before you get out of the car on a busy road hard shoulder to see where the smoke is coming from).  Problem with a turbo has always been that while one side is running red-hot the other side is running cold - plus as you compress incoming air it gets hotter and then you need an inter-cooler to cool the intake air down before feeding it into engine.

http://www.greencarreports.com/news/1082165_do-small-turbo-engines-really-give-better-gas-mileage

main problem is that although on paper you can improve the fuel efficiency of an engine with a turbo,  in real life it leads to very disappointing results, and you still have the added complication and reliability issues of the turbo (as well as the horrendous cost to replace them when they fail). Personally I would hate to see the legendary Honda reliability affected by the fact that they followed a fashion trend and were dragged down the same road as other lesser engine makers.

here is a excerpt from an American report  on downsizing to small turbo engines............

'An Escape equipped with the 2.0-liter EcoBoost engine only returned 22 mpg in a Consumer Reports test, the same as a 3.5-liter V-6 2013 Toyota RAV4--and lower than its EPA combined rating of 25 mpg'.
« Last Edit: February 28, 2014, 10:03:32 AM by culzean »
Some people will only consider you an expert if they agree with your point of view or advice,  when you give them advice they don't like they consider you an idiot

guest3418

  • Guest
Re: Honda's new generation of VTEC turbo engines
« Reply #16 on: March 02, 2014, 01:12:30 AM »
It all depends on how you use the engine. A 160bhp 2.0 engine and a 160bhp 1.4 turbo engine will probably use the same amount of fuel when using all of the 160bhp. The trick is that they are more efficient at medium loads like highway driving.
And on the subject on failing turbochargers, they are more likely to fail when you thrash the engine when it is still cold then by turning it off directly. The whole idling practice only comes into play when you do a lot of high speed highway driving and stop at a motorway service station or something like that. If you drive normally there is no need for idling.

Verstuurd vanaf mijn GT-N7100 met Tapatalk

culzean

  • Approved Member
  • *
  • Posts: 8017
  • Country: england
Re: Honda's new generation of VTEC turbo engines
« Reply #17 on: March 02, 2014, 07:51:13 AM »
No one can argue that turbo diesel engines are less reliable than their non-turbo equivalents, are more expensive to buy and maintain, are more complicated, are more highly stressed and as a result suffer more engine (as well as turbo) failures, and modern non-turbo gasoline engines are now the most reliable engine and easily do equivalent mileages (many 100,000's) without problems, they are cheaper to buy, the engines are lighter, they warm up quicker. Just when we have got petrol engines to this peak of efficiency and superb reliability we are going down the same route that causes problems in Diesels.   As I said before a Diesel runs on volumes of air,  the more you can push in the better, and they can run lean, and Diesel fuel is about 15% more energy dense than petrol,  which accounts for some of the extra mpg from a Diesel. A petrol engine has an ideal maximum air / fuel mix of 14.7:1 and no more,  the extra heat generated in turbo petrol engines has to be got rid of, reducing thermal efficiency, also to cool combustion a richer mixture ( lower air / fuel ratio) is used - using more petrol.  When you add all the plumbing and extra electronics and sensors required it is a complication with little or no benefit, and significant downsides.  Car manufacturers like any other business are subject to fashions,  if other people are using technology that promises 120mpg and 150BHP from a 600cc engine then other feel they have to do the same, it takes a while for the truth to come out about reliability and servicing costs, and also that the efficiency gains are not always what they seem, and when manufacturers test their engines they will always do it in the most advantageous way,  after all who sits at 50mph on the motorway all day,  car engines operate over a wide band from chugging around town to blasting down the autobahn, and no one technology can offer efficiency gains across this whole spectrum. Remember the old saying 'if something seems too good to be true, it probably is'
« Last Edit: March 02, 2014, 10:07:06 AM by culzean »
Some people will only consider you an expert if they agree with your point of view or advice,  when you give them advice they don't like they consider you an idiot

guest3418

  • Guest
Re: Honda's new generation of VTEC turbo engines
« Reply #18 on: March 02, 2014, 10:46:10 AM »
I have driven multiple turbocharged cars with a wide mileage range and there was never a turbo failure with one of them. Just stick to the oil change schedule, wait for the engine to be warm before thrashing it and when it is really hot (long distance high speed driving) leave it idling between 30 seconds and 1 minute before turning it off. People are scared for no reason at all. I will take a nice turbocharged engine any day. There are so much stories out there with no truth behind them... Take the Renault 1.5dci engine for example, loads of people claim that these engines will fail at max 150000km with either injector failure or turbo failure. Well my first 1.5dci powered car had 240.000km on it when I sold it and it was still running strong with the first set of injectors and the first turbo. The second one is now at 160.000km and counting after 3 years and this engine has to work hard for me (and both were Renaults with not a single electrical failure). The only car I ever had engine problems with was a.... Honda....

Verstuurd vanaf mijn GT-N7100 met Tapatalk


guest3331

  • Guest
Re: Honda's new generation of VTEC turbo engines
« Reply #19 on: March 07, 2014, 02:38:23 PM »
Yes, Ford's 3 cylinder 1 litre ecoboost engine gives very disappoining real world mpg.  According to the www.honestjohn.co.uk RealMPG retister - it's about the same as the old 1.6 in a Focus, getting about 35 40 mpg.

The VAG 1.2 TSIs get very decent results though.  Skoda Octavias getting high 40s.  Skoda Rapids getting mid 50s.  I've driven the 1.2 tsi in a polo and it gave a very engaging drive.  Lovely engine.

And then there's Honda's NA engines...  The 1.4 Civic's getting nearly 50mpg and the 1.8 is getting over 40.  The 1.8 in the current Civic is superb and I returned well over 50mpg in 7 hours mixed driving when I had one as a hire car

I'm kind of disappointed to see Honda going down the turbo route.   I can't help but think a lot of Honda's dominance in reliability statistics comes from a lack of Turbo engines and a limited diesel line-up.  Still, I guess small DI turbo engines are going to give some very good CO2 / mpg figures on the NEDC.  If Honda can maintain the reliability we expect from them, they'll be doing very well.

culzean

  • Approved Member
  • *
  • Posts: 8017
  • Country: england
Re: Honda's new generation of VTEC turbo engines
« Reply #20 on: March 08, 2014, 09:53:26 AM »
Well said Uriel - or as I sometimes say 'bullsh*t baffles brains' -  manufacturers like Ford can get a temporary boost in sales by promising people the Earth (literally) but the truth is bound to come out and their future credibility is damaged - I too hate to see Honda going down the turbo route on their superb NA petrol engines (Diesel is another case entirely).   I drive a 1.8 i-VTEC Civic every day and the engine is a masterclass in how to design an engine,  it will happily potter around smoothly at pedestrian speeds, but when required it can produce a very satisfying amount of useable power for overtaking and the gearbox is a joy to use. I get about 48 mpg in summer,  around 44 in winter - not too shabby for a 1.8 litre - and the exhaust noise at 7K rpm is 'boootifull'

As I said, Turbo Diesels are another case entirely and the Honda 1.6 i-DTEC engine is a new benchmark in engine design  (just one of the many benchmarks set by Honda) and deserves to sell by the boatload. 
Some people will only consider you an expert if they agree with your point of view or advice,  when you give them advice they don't like they consider you an idiot

guest3418

  • Guest
Re: Honda's new generation of VTEC turbo engines
« Reply #21 on: March 08, 2014, 09:22:37 PM »
The new diesel engine from Honda is very nice indeed. To bad they don't have it coupled to a decent automatic gearbox in de Civic estate. If they would fit it with either a DCT or a conventional automatic transmission it would have been a first choice for me as a new company car. I opted for a Peugeot 308SW instead with a 2.0 diesel with 150bhp and 370Nm. The French give the most kit for the buck in the leasing market, would rather have a Japanese car but they are either to expensive or not available in a configuration that I want.

Verstuurd vanaf mijn GT-N7100 met Tapatalk


RichardA

  • Topic Starter
  • Administrator
  • Approved Member
  • *
  • Posts: 3041
  • Country: gb
    • https://clubjazz.org
  • My Honda: 2007 1.4 i-DSi Sport manual
Re: Honda's new generation of VTEC turbo engines
« Reply #22 on: March 11, 2014, 09:47:42 PM »
I see Mazda with the new Mazda3, 6 and CX-5 have avoided going down the turbo-charging route. Do they know something the others don't?

olduser1

  • Approved Member
  • *
  • Posts: 1747
  • Country: 00
  • My Honda: Jazz EX 2015 CVT Elite Pack
Re: Honda's new generation of VTEC turbo engines
« Reply #23 on: March 12, 2014, 02:27:03 PM »
Mazda are still run by engineers who enjoy technical challenges, who else would have stuck with the rotary engine for so long. Their latest skyactiv -drive technology looks a good bet

madasafish

  • Approved Member
  • *
  • Posts: 1952
  • Country: gb
  • My Honda: 1.4 ES CVT -2012
Re: Honda's new generation of VTEC turbo engines
« Reply #24 on: March 13, 2014, 09:20:29 AM »
Mazda are run by people who get things wrong for years: rotary engines and their diesels spring to mind. see http://tinyurl.com/pnqbz3z

guest3331

  • Guest
Re: Honda's new generation of VTEC turbo engines
« Reply #25 on: March 13, 2014, 10:51:59 AM »
Mazda's 2009 - 2010 2.0 litre diesel with DPF, in particular, was a disaster waiting to happen for anyone that didn't check the oil regularly (like weekly).

If engine was switched off during a DPF regen, it would dump excess fuel in the sump.  The oil level could rise fairly quickly and if left unchecked could lead to runaway engine.

The subsequent 2011 ( I think) 2.2 is much better but they still have a nasty habit of stretching their timing chains and there are still some reports of DPF related oil rise (as post above).  Sounds like most problems were sorted out for the 2.2 skyactive diesel but it might be too soon for things like timing chain problems to emerge.

Warranty Direct published statistics on engine failures by manufacturer last year.  Honda was so far out in front of everyone else, it was almost unbelievable.  About twice as reliable as Toyota, who came 2nd.  http://www.autoexpress.co.uk/car-news/consumer-news/62383/german-cars-among-worst-engine-failures

guest4621

  • Guest
Re: Honda's new generation of VTEC turbo engines
« Reply #26 on: April 24, 2014, 03:46:03 PM »
I'd be up for a small turbo-charged lump in the new Jazz especially if they are looking at a Type S / Si model. I've had a VAG turbo petrol and several TDs - as said above a lot of the issues are down to how you look after them. My first TD (Vaux Astra 1.7) I was 18 and ragged it everywhere, never let it cool down, etc.. un-suprisingly the turbo died at 80k, followed by the gearbox at 110k. My VAG petrol turbo ran happily to over 100k with only discs, pads and filters being replaced.

It just needs to be enginerred correctly and not stretched too far - e.g. Fabia Vrs 1.4TSI, which are renowned for engine issues. I'm pretty confident that with Honda's knowledge, of how to build a solid engine, there will be anything to worry about. I know several CTR owners who run over 400bhp at the wheels from K20s.

Tags: jazz news 
 

Back to top