V6 vs V8


#1

Hello. I’ve been driving a Caddy V8 a number of years…love the power, though not really needed most of the time. I am concerned about going to a V6, however, posts on many sites SAY the V6 has as much power as a V8 these days (obviously I know nothing about these things or I wouldn’t be here). I am looking for some expert advice here. V6’s are, generally, easier to find and a bit cheaper, especially in Caddys. Let me know your opinion and what you base it on. Appreciate your time and input. Thanks!


#2

Some V-6s have more power than a lot of V-8s but (and this is just my opinion) what is more critical to me is torque and how it’s applied. That is what makes driving more pleasant throughout most of the range of driving.

You might see a horsepower figure touted as XXX horsepower on a V-6 but that figure might be at 5500 RPM with a narrower powerband. You have to ask yourself how often you will ever run an engine up to 5500. The usual answer is never unless drunk, ticked off, or drag racing; or maybe all 3 at the same time… :slight_smile:

You might do a net search about automotive powerbands or torque curves as it’s called. A few charts and graphs would probably put it in a better perspective than any lame explanation I give.
What I usually look for in an engine is the power characteristics from off-idle up to about 3500 RPM because that’s where the bulk of most driving is done unless the pedal is nailed to the floor.


#3

Based on the power of the 2.5 four cylinder in the Rav4, any V-6 will have lots of power. The Rav weighs 3,200 pounds with AWD. There is no shortage of power these days.


#4

I wouldn’t worry about it myself, but you’ll just need to do a test drive. I used to have V8s and sitll have one but I’ve had maybe 6 or 7 V6s and have two now and I sure wouldn’t be able to tell the difference. Combined I’ve put maybe a million miles on them with no major problems, and I usually get upwards to 30 mpg.


#5

Forget about using the number of cylinders as an indicator of how much acceleration the car will have or of how smooth it’ll run. There are even four cylinders now that are as peppy and smooth as many 8 cylinder engines of just 20 years ago, and bolted to six, seven, or eight speed transmission they can perform very well. Just 9 years ago I tested both a four cylinder Camry and a V6 Camry (the 4-banger might have actually been a bit better), and the performance, smoothness, and quietude was indistinguishable between the two. Engines now have far better fuel management, more consistent cylinders, and even balance shafts to counter the vibrations inherent in operation. And many V8s now have “cylinder management” that shuts off cylinders whenever possible, meaning they run as four cylinders anyway.

Let your test drives determine the one you like best. Don’t even look at the engine size. Let your senses be your guide, not the numbers on the trunk lid.


#6

The current trend of propulsion technology is to use a high revving engine and more gears than you care to count. You push the engine to the higher range to get hill climbing power and stay in the lower range while cruising. While it sounds harsh compared to the big low revving engines in the past, the engine will survive just fine as long as you keep
up with the maintenance. Also, you are carrying a lighter, smaller engine.


#7

I suggest you read up on the specific models you’re interested and see what they say. On one model the V8 may be just right and the V6 underpowered, but that V6 might be just right in another model, where the V8 would be more engine than the car needs. The right engine could be either one, depending on YOUR needsbvb. Things have gotten less clear in recent years with direct injection and forced induction (either turbocharging or an engine-driven supercharger) have increased the powe of small engines. Even sporty BMW is using a lot of fours, even as an option in larger models. All this means the cylimder count means less than it did. Many small cars are coming with a 1.8 or 2.0 liter four in the cheap versions, with a 1.4 liter turbo four as the premium engine.


#8

The best way to find out if it’s peppy enough it to drive one with a V6. I haven’t owned a V8 in over 30 years. The V6 I have in my 4runner has more HP and Torque then the last V8 I ever owned. Forget the numbers…just drive.


#9

Next to no V8 cars available now. The V6 is absolutely fine as far as power for a car goes, and with a turbo they’re now being used in pickup trucks, SUVs, etc. So don’t worry about the engine. Test drive a number of cars that meet your needs, buy the one you like. It really is that simple.


#10
The V6 is absolutely fine as far as power for a car goes, and with a turbo they're now being used in pickup trucks, SUVs, etc.

NOW being used. V6’s have been in full-size pickups for years. My dad had a V6 in his 1973 GMC pickup. GMC’s 305 V6 was standard in the 60’s.


#11

The best and only way to really know is to take it for a test drive. That is the only way to know what the power feels like and when it is actually available. Someone mentioned the V6 Rav4 - I am a big fan of this car because the power is always ready and available, with no delay when depressing the pedal. A lot of other vehicles even with similarly sized engines take a few moments for the engine to really kick in.


#12

Which model Cadillac are you looking at? The CTS I s available with a 4,6,or 8 cyl. If you are interested in the 8 cyl, it will not only cost more but scare the day lights out of you it’s so quick. You really should take race car driving instruction if you want the CTS-V.


#13

First, many thanks to all of you who took the time to respond, it was most helpful…you guys really know your stuff!! I should have mentioned I was looking at the Cadillac STS '05-'07 models (I have an STS now). Point being, it is the smaller Cadillac sedan (as opposed to, say, the DTS or other larger models); I won’t be doing any towing with it. As you probably know, the older STS I am driving has the Northstar V8 and this thing takes off like a rocket if you want it to, which I like (especially for getting around the Clampett’s on a 2 lane highway). Yes, the advice to test drive is, of course, correct. But where I live in Idaho you can’t even find a Cadillac—or a dealer—for at least 200 miles. I’ll take the advice given here to mean that a V6 will do the job these days. Now, the last fellow mentioned the CTS, which I’m also looking at, which appears a bit bigger than the older STS models. Again, not sure it matters for my purposes. I won’t be getting drunk, pissed off, or drag racing anytime soon. :wink: I just want to be able to take a hill, pass the Clampett’s, or get out of an ugly situation quickly…and I’m not that concerned about the lesser gas mileage. Sounds like you would all be fine with a V6. Thanks, again!!


#14

The CTS is a bit smaller than the STS, you’ll find a CTS with the 3.6 liter V6 to be quite capable.


#15

O.K., thanks, showing my ignorance again…which is easy for me in this forum. Yours and everyone’s advice here has really helped me with my buying decision.


#16

When you talk about the evolution of motors, v6, v8 etc., you must include in the discussion the transmission used for each. The evolution in the performance of the trans mission as aided by the computer has a dramatic affect on how well a motor performs. A 6 speed auto can make an acceptable vehicle out of a dog for a motor preciously saddled with a 4 speed. The same is true comparing older v8s with modern 6 cylinders.


#17

I hoped you weren’t looking at the CTS-V. The V6 in that car will work for you. Look for old test reports on line to see what the acceleration is like. That’s not a substitute for a test drive, but will give you a basis for comparison with your STS. Also, check are dealer web sites for inventory. A CTS might show up on any dealer’s lot. Start close to home and expand the search until you find one to test drive. You might also look at Craigslist for CTS cars for sale near you. You don’t have to drive it, just test drove it. Then decide if a CTS works for you.


#18

The mpg’s has started to become more important then the G’s at blastoff,most vehicles are capable now(except for my 4wd dakota V-6{power of a four,mileage of an eight}-Kevin


#19

Caddy V-8’s have not set any high-water marks for reliability, longevity, serviceability, or anything else since about 1980…When the Northstar’s reputation went negative they quietly starting using various versions of the 1955 Chevy pushrod V8, with excellent results…But those days are over too…The latest Caddy’s offer 420HP from a DOHC turbocharged V6 engine that can hold it’s place on the road…

http://www.autotrader.com/research/article/car-news/205370/2014-cadillac-cts-to-offer-twin-turbo-v6.jsp


#20

I was logged onto the GM technical website today

Anyways, I saw a bulletin which was apparently released just this week

It concerned the high feature V6. The bulletin explained the criteria for replacing an engine, due to worn/damaged bearings

Not very confidence-inspiring

I’ll be sure to NOT run out and buy a GM with that engine

The fact that the bulletin even exists, suggests . . . to me, anyways . . . that the engine has severe problems which refuse to go away

Every manufacturer has had their problematic POS engine design. And this appears to be a problem child