Soldato
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And?
Get in a B18C and you will see what the deal with VTEC is over other valve timing technologies.
Turbo vs NA
- Thread starter khevolution
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And?
Get in a B18C and you will see what the deal with VTEC is over other valve timing technologies.
Soldato
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there are a few scenarios to play with here……
i would take a nice D turbo auto for lazy, effortless motorway cruising and round town comfort and as I have low expectations, a volvo s60 d5 would do but I would favour a 530/535d. if I could live with the fuel bill a large capacity petrol gt type cruiser every time.
for achieving a great real world driving experience, you don’t need highly tuned turbo engines or huge capacity, just the right chassis, so a civic type r or renaultsport clio of any era will do.
most of the time, you run out of road before performance in the uk. a small capacity turbo engine like the corsa vxr may be ok but I wouldn’t choose one over the fore-mentioned n/a hot hatches.
an average hatch with a turbo petrol / diesel will feel quicker than its n/a equivalent, even if it isn’t on paper since, the small/medium capacity turbo engines do benefit from a better mid-range and in gear acceleration. this can be very noticeable in every day driving. on a track this becomes less of an advantage when to put it politely, you can rag the nuts of the n/a engine and keep it in the power band.
mitsi evos prove you can make low capacity high power turbo petrols extremely fast…..if you want that type of car and driving experience.
perfect car for me would have to be a C2S or C4S…
i would take a nice D turbo auto for lazy, effortless motorway cruising and round town comfort and as I have low expectations, a volvo s60 d5 would do but I would favour a 530/535d. if I could live with the fuel bill a large capacity petrol gt type cruiser every time.
for achieving a great real world driving experience, you don’t need highly tuned turbo engines or huge capacity, just the right chassis, so a civic type r or renaultsport clio of any era will do.
most of the time, you run out of road before performance in the uk. a small capacity turbo engine like the corsa vxr may be ok but I wouldn’t choose one over the fore-mentioned n/a hot hatches.
an average hatch with a turbo petrol / diesel will feel quicker than its n/a equivalent, even if it isn’t on paper since, the small/medium capacity turbo engines do benefit from a better mid-range and in gear acceleration. this can be very noticeable in every day driving. on a track this becomes less of an advantage when to put it politely, you can rag the nuts of the n/a engine and keep it in the power band.
mitsi evos prove you can make low capacity high power turbo petrols extremely fast…..if you want that type of car and driving experience.
perfect car for me would have to be a C2S or C4S…
I'm sure it's a nice technology, but a quick check on wikipedia and you are referring to a roughly 200 horse power engine?
... so how is that so superior to say, a BMW VANOS equipped engine (E46, E60, E92) so much so that it could be compared to a turbo or supercharged engine?
... so how is that so superior to say, a BMW VANOS equipped engine (E46, E60, E92) so much so that it could be compared to a turbo or supercharged engine?
Soldato
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Its not comparable with paper, this is a subjective assessment, often the fastest cars can dull the actual driving experience. The 1.8 is typical for that class/size of car. What makes it then special is the +100bhp/litre.
Pulls like a train not accelerates like a train.
"Pulls like a train" I an expression which means unstoppable pull of the kind offered by a very powerful locomotive.
As it is a metaphor that has been used to describe powerful cars almost since their invention it really isn't him wrong is it.
The E46 had 100bhp per litre also, and the VANOS gave a similar high rpm 'on cam' feel to it which made the top end seem more and more mental as you kept giving it beans.
Great technologies for sure, but i think it muddies the discussion between comparing forced induction with N/A engines.
.... although i suppose the scene was set when someone was talking about how they prefered an N/A engine with a supercharger ... haha.
Which one that isn't a turbo diesel or M3? The petrols are mostly around 70-80 HP per litre and are well off the pace of the specific output of VTEC cars of the era!
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The M3 was a very expensive sports coupe with a 3.2 litre engine, so not at all similar to what most 1.8 VTEC hatchbacks were. Additionally, the M3s performance credentials were almost nothing to do with VANOS, but I suppose much in the same way that most 1.8 VTEC nutjob engines were not much really to do with VTEC.
Comparing a Petrol turbo with a diesel turbo is a bit pointless.
A Diesel uses a turbo to increase efficiency as well as power.
A petrol turbo is purely to increase power.
The size of turbo is not the only thing that effects lag. Compression ratio, design of exhaust manifold etc can also contribute aswell as the exhaust housing on the turbo itself.
Modern turbos tend to be smaller for faster response which it seems is what people want. Larger turbos are what i prefer from experience i love the kick of the lag and it completely depends how you drive the car. Large turbos with lots of power are not needed on the road. I did track days in my cosworth as well as the nurburgring and had no trouble keeping her on boost on the road however I could be done off the lights by a saxo vts with a quarter of the power.
I also owned an RX 7 which by default had small twin turbos good for 330bhp ish i ditched these in favor of a large single turbo not to achieve the higher HP but because i loved the kick.
Infact the only Turbo Petrol car I have owned I did not upgrade the turbo to a bigger single unit on was my Seat LCR but I was over spending money on cars by that point and wanted something more reliable
.
If i could afford it right now i would love an older 3 door cosworth again or possible an Evo with a big huge turbo.
A Diesel uses a turbo to increase efficiency as well as power.
A petrol turbo is purely to increase power.
The size of turbo is not the only thing that effects lag. Compression ratio, design of exhaust manifold etc can also contribute aswell as the exhaust housing on the turbo itself.
Modern turbos tend to be smaller for faster response which it seems is what people want. Larger turbos are what i prefer from experience i love the kick of the lag and it completely depends how you drive the car. Large turbos with lots of power are not needed on the road. I did track days in my cosworth as well as the nurburgring and had no trouble keeping her on boost on the road however I could be done off the lights by a saxo vts with a quarter of the power.
I also owned an RX 7 which by default had small twin turbos good for 330bhp ish i ditched these in favor of a large single turbo not to achieve the higher HP but because i loved the kick.
Infact the only Turbo Petrol car I have owned I did not upgrade the turbo to a bigger single unit on was my Seat LCR but I was over spending money on cars by that point and wanted something more reliable
.If i could afford it right now i would love an older 3 door cosworth again or possible an Evo with a big huge turbo.
You tried to make the point that VANOS is no different to VTEC. That would be valid if BMW applied it in the same way as VTEC, which they do not. From a technical and engineering perspective, sure, but it doesn't get packaged and put on the roads to compete with it. Almost every manufacturer is implementing these sorts of systems in their high-end large-displacement sports cars, but Honda were one of the few putting it in to smaller capacities. For that reason, in the context of smaller capacity engines, VANOS is not equivalent and almost needn't be discussed; it, and similar technologies, can be assumed to be present in the class where BMW have utilised it fully.
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Soldato
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I think the M3 was overlooked as your comparing displacement to turbos etc then the M3 pulls the displacement card, a typical VTEC applications
cation has neither displacement or FI.
Could move the 1999 S2000 if you want to talk about silly bhp/litre?
Interesting discussion and some valid points from various people. Hang on...I'm in OCUK motors forum. That's not normal? 
I have driven various and to be honest I don't have a favourite as each car has it's own characterisitcs and it depends as a package how well it works in line with the chassis/weight etc. Yeah I know...get off the fence. Well if I had to chose it would be supercharged.
I like forced induction. To be honest I don't mind even large turbo lag as long as the power to come is worth it. On a track day however, that could become an issue.
I have driven various and to be honest I don't have a favourite as each car has it's own characterisitcs and it depends as a package how well it works in line with the chassis/weight etc. Yeah I know...get off the fence. Well if I had to chose it would be supercharged.
I like forced induction. To be honest I don't mind even large turbo lag as long as the power to come is worth it. On a track day however, that could become an issue.
How about on the Alfa Twinspark engines - which also used a similar system?
It seems like quite a restricted criteria for comparrison, if high performance cars, or ones not achieving a magic 100bhp/litre are being excluded
... i would have imagined this was more about predictable, linear power delivery curves, versus the variable nature of forced induction engines, depending on how well they have been engineered.
Personally, i wouldnt want to place any trust in a car delivering unpredictable bursts of power at inappropriate times - Which is why i hated my saab, yet loved driving a biturbo audi V8 which had little to no perceiveable lag.
It seems like quite a restricted criteria for comparrison, if high performance cars, or ones not achieving a magic 100bhp/litre are being excluded
... i would have imagined this was more about predictable, linear power delivery curves, versus the variable nature of forced induction engines, depending on how well they have been engineered.
Personally, i wouldnt want to place any trust in a car delivering unpredictable bursts of power at inappropriate times - Which is why i hated my saab, yet loved driving a biturbo audi V8 which had little to no perceiveable lag.
You need to learn to drive a car with a large laggy turbo.
As the above comment people see it as unpredictable which it is not at all. Its all controlled with the right foot.
Add to that most of the cars with said size turbo tend to be RWD high burst of power and RWD are awesome when you can tame them.
I crashed my first cosworth underestimating this. I bought a diesel rover and did track days in my cosworth once id rebuilt it to get used to it.
Most cars today are FWD RWD and 4wd tend to be more expensive and many people have not driven them.
Put someone who has driven only FWD cars into a high power RWD and there will be an accident.
As the above comment people see it as unpredictable which it is not at all. Its all controlled with the right foot.
Add to that most of the cars with said size turbo tend to be RWD high burst of power and RWD are awesome when you can tame them.
I crashed my first cosworth underestimating this. I bought a diesel rover and did track days in my cosworth once id rebuilt it to get used to it.
Most cars today are FWD RWD and 4wd tend to be more expensive and many people have not driven them.
Put someone who has driven only FWD cars into a high power RWD and there will be an accident.
I think we are having a disconnect here
Sure, Alfa Twin Spark engines were of a similar displacement and in competing models, however it was then way off the pace of the better VTEC power/litre and Alfa chose to use displacement in, for example, the GTA.
VTEC has become synonymous with higher-power small-displacement engines. Take the Civic Type-R EK9; introduced in 1998, it featured 185 HP from a 1.6L, giving it 116 HP/litre. It had a very distinctive driving style and nobody else was coming close at the time. The EP3 successor, introduced in 2001, made 200 HP from a 2.0L. The car retailed at £20,000. Toyota had something similar in the VVTL-i Celica, but that was about it. VANOS, Twin Spark and all the other technologies were never packaged and offered in such applications.
VTEC is by far the most prolific and well-known of the technologies used to enhance small-capacity engine performance in everyday cars. Combine that with virtually no competition in this market, I think it's very fare for people to imagine VTEC as an entire performance delivery style unto itself; it basically is!
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Sorry but you are just wrong, a turbocharger increases efficiency on a petrol engine as well.
Turbo chargers increase volumetric and thermodynamic efficiency by using hot, still rapidly expanding, waste exhaust gases to power something that would otherwise have to be driven by the engine.
A supercharger focuses more on increasing volumetric efficiency.
In terms of efficiency, a turbo is pretty much "something for nothing" compared to a N/A engine. I think what you meant was that Turbos have a more marked impact on efficiency of a diesel than a petrol?