What are the advantages and disadvantages on a 4 cylinder verses 6 cylinder
engine for cars-SUV’s these days ?
New crossover SUV to me this year and starting the search. I drive a fair bit, and would say on average every week I do a drive of 2-4 hours round trip. Just wondering if I should have the 4 verses 6 cylinder a high consideration or not.
Thanks in advance to you knowledgeable car folk out there.
Four cylinder engines tend to be more fuel-efficient, getting better gas mileage. Six cylinder engines tend to be a bit heavier and peppier. “Stepping on it” in a six-cylinder engine is likely to get you faster acceleration than a corresponding four-cylinder. A six is also typically heavier and you might be able to feel differences in inertia when braking.
Better gas mileage for one, and less moving parts to break down for another, but it really depends on what kind of driving you do and where you live.
If your car is fully loaded (with people or stuff) and you live in the mountains and are driving up steep roads everyday then a 4 cylinder may not make a lot of sense.
However if you live in the flat lands, do mostly highway driving, and are typically alone in your car and not carrying a lot of stuff then a 4 cylinder may work just fine for you, and save you money on gas every week.
Some 4 cylinders have almost as much power as some 6 cylinders, so it depends to some degree which car you are considering getting.
I would suggest you test drive both, or perhaps rent both types for a week if you can swing that, and see which works better for you. You may decide that you need more pep than a 4 cylinder can muster, or that a 6 cylinder is a waste of power.
Well, there’s a lot of leeway in a lot of things, but basically a V6 is going to have noticeably more power than any 4 cylinder. Conversely a four-cylinder is going to get noticeably better gas mileage than a V6. There are extremes on both sides that may contradict this a little, but that’s the gist of it.
In terms of a crossover SUV I would favor the 4 cylinder, because ‘crossover’ essentially just means a ‘small’ SUV, no towing or hauling big loads etc. If you need to do either of those do not get a crossover and certainly donot get a four cylinder. And if you drive that much I would consider gas mileage to be a priority.
One thing: If you’re considering a Subaru note that their four cylinder engines are flat-4s or ‘boxer’ engines, similar to the style the old VW Beetles had (but not air-cooled). They are very reliable, but those engines have a distinctly different feel and sound to them which some don’t care for (myself included).
If you’d like to keep long-term maintenance costs down, get an engine with timing chain(s) instead of belt(s). Timing belts have to be replaced periodically while chains don’t.
Ultimately the main thing that determines how much power an engine produces is how much air/fuel is being burned per unit time. That’s why larger displacement engines (more volume) engines are more powerful, all else being equal. They also (obviously) burn more fuel to generate that power.
As a result, for the same displacement, a 4 and a 6 cylinder engine will have similar power, and similar fuel economy, with both being slightly higher for the 6 cylinder, all else being equal.
But… these days, I’d go with a combination of fuel economy and test drive to make the choice, because “all else” is rarely equal anymore. Things like turbo and superchargers and stratified charge burning, and the like change the playing field and make things much less dependent on straight-up displacement or # of cylinders.
AFAIK, all moderately-priced OHC engines use belts. Only the shrinking number of OHV 6 and 8 cylinder engines and OHC’s in fairly expensive tiers use chains.
Do *any *moderately-priced cars with OHC engines use chains with more durability than belts?
My personal experience with cars is that a 4 cylinder will get better mileage, and with today’s transmissions will still be surprisingly peppy, if it is a small and lightweight car. However, if you are going at highway speeds and need to stomp on it, or you need to go up a big hill (I occasionally have to drive up a few West Virginia mountains), the performance of a 4 cylinder will be noticeably lacking. A 6 cylinder won’t be too much peppier on flat ground, but will have a very noticeable improvement in performance when going up steep hills or when the acceleration as at the top end.
My experience with larger vehicles (minivans and SUVs) is that 4 cylinders do get better mileage, but surprisingly it’s not that much better, and their overall performance in these larger vehicles is sluggish.
This is just speaking in generalities from personal experience though. It is entirely possible for a specific 4 cylinder engine to actually be more powerful than another specific 6 cylinder engine. So literally, YMMV.
Ding! This is the right answer. There are so many differences between cars that you simply can’t boil a decision down to cylinder count. Go look at cars, look at the specs (mileage, safety ratings, etc.), test drive some, then buy the one you want. After all, you’ll be the one driving it, you’d better find one that you like and that works well for you.
It’s a lot trickier to make blanket statements about “V6 versus 4 cylinder” than it once was. On a few cars the V6 is the economy engine and a turbocharged 4 cylinder is the upgrade. Others may just have a whole myriad of 4 cylinders options some of which would be comparable to a V6. You really do just have to consider the particular engine you’re looking at without worrying too much about the number of cylinders.
Pretty much everyone is going to chains these days, thankfully.
As far as disadvantages - for the 6 cyl, it’s simply cost. For models that offer the option between a 4 or 6 cylinder engine, the 6 cyl is more costly. Also, 4 cyl engines generally get better mileage (so more $ for gas with a 6 cyl), but this gap has been closing over the years. The gap will also vary by model and transmission. With some CVT transmissions, the difference in mileage is practically negligible (some only 1-2 MPG difference).
Some car makers, Ford specifically, is mating their smaller engines to a turbo. They call this their “eco-boost” option. Instead of a 6 cyl in a midsize car or small SUV/Crossover type, they drop in the 4 cyl with a turbo charger, increasing the power to weight ratio without sacrificing any fuel economy (theoretically at least - depends more on how you drive). But the cost of the Ford eco-boost option is higher.
You may also want to consider if you do any towing whatsoever or if you think you might want to tow some sort of trailer in the future. A larger engine will tow better, all else being equal.
During the summer, my wife had surgery at Stanford, requiring the rental of a car for each trip. Fourteen cars in all, a mix of cross-overs, minivans, fullsize(6 cyl.) and mid/small size(4 cyl). Almost all freeway (135-140 miles) with a couple of modest climbs(Altamont Pass, Sunol grade), 10 miles in-town and 15-20 miles stop-n-go on the return trip.
All but one vehicle fell within a 28-30 mpg window. The one outlier gave 23.
I am now driving a 2001 VW Passat with a 6-cylinder engine. My previous car was a 1996 VW Jetta with a 4-cylinder engine. There is no comparison! The difference in mileage is small. On a trip to Cincinnati from Columbus last summer, I got 31mpg using the air conditioning. Today’s 6-cylinder engines are so much superior it is scary! But the same thing is happening with 4-cylinder engines. Nonetheless, I would say go with a 6-cylinder engine.
All else being equal (including displacement), I’d expect a 4-cyl to have better efficiency than a 6-cyl. Heat loss to the cylinder walls during the power stroke is an important inefficiency; energy pissed away through the radiator is energy that’s not being used to move the car. For equal total displacement, a 4-cyl is going to have less combustion chamber surface area, on a per-unit-volume basis, than the 6-cyl - and therefore less heat loss.
That said, it’s pretty hard to find one vehicle that can provide a direct comparison between 4-bangers and V6’s of equal total displacement.
Try comparing the horsepower to weight ratio of the engine to the entire car. Add your weight plus 50 pounds for your “stuff” when doing the calculations.