Hello I am new to this forum. I have a 1.6 engine car (VW Passat 2006) with 115 HP that I want to change due to being quite slow on acceleration (0-60 mph in 11 seconds) and other issues specific to this car
I came across a V8 engine car with 270 or 280 HP 2002 Lexus GS430) that accelerates much faster but miles per gallon and full tank fuel efficiency figures found online for these cars’ specs suggest that the V8 engine is around 33% less efficient than the 1.6 engine. The V8 car is also around 200 kg heavier.
Will these figures translate this accurately into day to day driving on normal roads with any speed limits from 20 to 70 mph? In other words, do I need to put in around 33% more fuel in the V8 car to travel the exact same routes and distances as the 1.6 car, with the same speeds?
Considering that the V8 engine is exponentially bigger than the 1.6, it requires a lot less power to travel at these speeds and roads than the 1.6 which uses a lot more power due to being much smaller. Is this hypothesis valid for day to day driving and will this compensate on the 33% less fuel efficiency estimate? Thanks in advance for the help.
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Ignore the engine size and concentrate on its power and weight. The larger engine produces 2.3 times the power. To do that it needs 2.3 times the fuel. The Lexus is 200 kg heavier so it needs more fuel to accelerate that extra weight.
And everytime you use that extra power to accelerate more quickly you will use more fuel. Significantly more fuel.
You WILL use more fuel for both reasons in the Lexus. Likely more than 33%
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Fuel efficiency is about so much more than engine power and efficiency. Aerodynamics play a huge role and other factors such as the transmission type and tuning also play a big role. A bigger V8 car with more weight will have bigger tires resulting in more rolling resistance and more rotating weight.
Most importantly, when you have a V8 car you will most likely take advantage of that superior acceleration, which is a very inefficient use of fuel. I drive a turbo charged 2.5 liter 4 cylinder that makes 255 HP. When I drive it on the highway at reasonable speeds and not mashing the accelerator to pass I get around 30mpg. When I am racing around town in stop and go driving, that number drops down into the mid to low 20’s.
To answer your question, that 1.6 liter is going to be way more fuel efficient than the V8 Lexus, even with all the other factors described by you.
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To me a 33% increase is the best you could do, more like 50%, I would think.
As for ‘why, they’re both putting out about the same hp in normal driving’ - engines are more efficient at higher loads, so a small engine putting out 20 hp is typically more efficient than a big engine putting out the same hp, but at half the load.
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I had a 2009 Dodge Challenger with the 5.7L V8. It got around 20-22 MPG overall.
Recently I traded it in for a 2016 Mazda 3 with a 2.0L 4 cylinder engine. It gets around 40-45MPG on average.
So basically double the MPG for about 1/3 of the engine size. I know it’s not apples to apples… but I sure like having to pay half as much for gas.
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Thanks everyone for the replies. I forgot to mention I just passed driving test less than a year ago so I am still new to driving and cars. I will stick around in case I will have other questions.
I’ve decided not to go for the Lexus and instead I came across a 2.4 L Volvo that I will probably see which might be just as reliable but considerably more efficient on fuel.
The key word in that sentence is “might”. Many veteran members of this forum advise buying a Volvo only as a new car, and getting rid of it as soon as the warranty expires, in order to avoid VERY expensive repair bills.
Personally, after buying a new Volvo–and maintaining it meticulously–I would never again buy a Volvo.
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Hello, thanks for your answer. As far as I researched new Volvos are not very reliable, whereas old Volvos are better built and can last many years. Is this hypothesis therefore not valid? What you are suggesting seems to be that Volvos, either old or new are prone to constant repairs and very expensive parts (as, considerably more expensive than other brands?)
I’ve been driving 2 cars already but I am looking to settle with a reliable car (ideally cheaper to repair) for the years to come as I am not a kind of person to change things every 1-2 years or related.
Older Volvos are parked at 683 Riverside Dr. Augusta Maine. It Googles well.
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You are posting questions about a 21 year old Lexus. Any car that old will not be reliable. Older than the one you drive now.
Cars with lots of technolgy will be even less reliable and more expensive to repair. Volvos fit that example. Lexus as well.
If you are driving a 1.6 Passat you do not live in the USA since VW did not sell that engine in the USA. Your selection of vehicle will depend on availability of parts in your country.
Most posters on this forum are from the USA, just FYI.
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If you want to increase power without increasing fuel consumption, consider getting a larger displacement engine with the same number of cylinders, or getting VVT so it can be tuned on the fly for high end performance, or adding forced air induction.
Increasing the size of the cylinders increases the torque and power without adding nearly as much more friction and thermal loss compared to adding more cylinders. A transmission with taller gearing is still needed to reduce the engine speed though after the displacement was increased.
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I live in UK. Volvos are not necessarily uncommon here but definitely they are not as common as Volkswagen or Ford. I would imagine Volvos are not very popular in US
The issue for me is that here in UK monthly car insurance is very expensive for a new driver and I found out that the older a car is, the cheaper it is to insure. If I want a car with a little bit more acceleration power then it has to be older for cheaper insurance, otherwise a car some 5-10 years old newer (say 2008+) with the same engine is going to be easily 50% more expensive to insure.
I tend to dislike newer cars due to being overly computerised, having poorer quality components compared to older cars (maybe not in all cases but as a rule of thumb) and being much more complex in electronics and sensors and more difficult to repair.
I don’t know in US but in UK is very common to see surprisingly new cars waiting for recovery on the highways (and other roads) quite often.
Maybe newer cars need less repairing than older cars due to parts being newer and the car having done a lot less miles, while in older cars components can start falling apart due to age and many more miles (generally but there are many old cars with very low mileage for their age)
Age is a problem too. A 30 year old car with 20,000 miles is a concern. In the UK rust would be some concern but rubber deterioration less… cool moist weather helps rubber, but creates rust. Oil, gaskets, lubricants, coolant, brake fluid and fuel all create problems if left to sit for decades without use.
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As far as my experience goes–no, it is not valid.
Others may have had better experiences, but my entirely negative history with Volvos dates back ~40 years.
My Volvo had electrical/electronic problems from the first week that I owned it, and serious mechanical issues continually cropped-up over the next few years. By the time that it got to 76k miles, I dumped it because there was no point in sinking more cash into repairing that money pit.
It would be difficult for me to conceive of modern cars that use poorer quality components than Volvo used.
That Volvo was the only car I ever owned that I had to dump because of its many serious issues, which began very shortly after I bought the car. By contrast, my subsequent cars (Chevy, Ford, Honda, 3 Subarus) were traded-in because my vehicular needs had changed or I simply wanted to reward myself with something newer.
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Thanks for sharing your experience. I have read reviews of people who owned Volvos and indeed many of them had issues with them, the best point for Volvos being that they are very comfortable.
Today I came across a 2007 Honda Accord with same mileage that I will see the following days but it is Diesel and much more fuel efficient apparently (51 mpg in average vs 31 for the Volvo).
Hondas have a good reputation as far as I know so maybe economically and realiability-wise is a better option. I read Honda Accord are also cheaper to maintain, although being 16 years old may not reflect the same performances in terms of reliability and maintenance costs as concluded in that particular article.
Indeed most likely this is the case. Most people use low mileage as an “advantage” of the car despite being 20+ years old. I recall there was a 2002 or so Lexus with only 8.000 miles that was advertised for what seems to be around $17.000 or so, and same cars with over 150.000 miles would sell for 5 times less or more. That car had this price and might very well have some or all of the issues that you listed
Are there Toyotas rebadged as a British brand? That might be an option, if (and goes for ant car) well maintained.
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Hello. There are lots of Toyotas in UK, they are very popular (most Japanese and Korean brands are). I am looking for a car that is some 2 seconds faster in acceleration than my current Passat. 0-60 acceleration time is how I “measure” this. I am not sure if this is accurate enough but is the only marker I know to estimate acceleration time from a low speed, so I don’t end up with angry drivers behind me for being too slow when entering high-speed roads that have a very short slip road for example, or when going at traffic lights or after turning from a busy junction.
The passat goes 0 - 60 mph in around 11 seconds and I considered a car that goes 0 - 60 in 9 seconds or less should fix the issue.
I haven’t really found any Toyotas to meet this that are also cheap enough as I am not willing to spend more than $2200 for a car. I had enough of pumping thousands and thousands in the Passat and the Nissan Qashqai I had before, in their prices and subsequent costly repairings that probably added to nearly 40-50% the prices of the cars.
Really? My girlfriend has a base model 07, 4 cylinder Camry, breaks the tires loose easily. Very responsive up to about 60 MPH then starts to lose power.
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