Car Question: V6 or V8?

[SpyderEdgeForever]

What are some of the notable differences between the two as far as road performance goes, and, which do you prefer?

If you could have any custom-built sports car, muscle car, or roadster, with money and cost as no object, which would you go for?

[jmh58]

Well.. Out of those two it would be a HiPo V-8.. Being an old gearhead.. Its all about HP!!! But a V-12 would be over the top!!! John :)

[bearfacedkiller]

If I won the lotto and could buy any car it would be a heavily modified GTR.

Maybe a NISMO like this one. It is a twin turbo 3.8 V6 with 600HP. :D
http://www.nissanusa.com/sportscars/gt- ... nismo.html" target="_blank

[tvenuto]

What are some of the notable differences between the two as far as road performance goes, and, which do you prefer?

This is similar to asking whether you notice a difference in cutting performance between a 3" or 4" blade. If the 4" blade is poorly made, then you may notice that the 3" blade is better, but it might not be because of the length. I personally have a V6 Accord and would trade it for absolutely no comparably priced V8 cars.

If you could have any custom-built sports car, muscle car, or roadster, with money and cost as no object, which would you go for?

I really absolutely have no idea. It would probably not be a muscle car, I bought a 1970 Barracuda back in the day and didn't enjoy its quirkiness. I could obviously pick one one of the many boner-inducing standards, but I've never even been in, much less driven, any of them. So I guess the best answer is that I'd call the who's who of car makers to a track one day, and tell them that they are competing for my blank check. That'd be a fun day.

[Evil D]

The biggest and most obvious difference is going to be torque, as the V8 will most likely always make more torque than a V6 UNLESS you start playing with cubic inches....there's a saying in the car world "there's no replacement for displacement". That means, the number of cylinders is only part of the equation...cubic inches is the real number to pay attention to, as in most cases this almost always equals more torque. There are V12s that have less displacement than V8s. Peterbilt used to make a 9.0 liter V6. There are 4 cylinder engines that have similar displacement as some F1 V12s.

What this all boils down to though, is application. Those 9L V6 engines that Peterbilt used to make probably never rev higher than 3-4k RPM at the most and make pretty much all of their power at very low RPM. As such, the internals move relatively slow and so they have less chance of breaking under extreme loads. Meanwhile, those small displacement V12s used in F1 have revved as high as 20k RPM and make all their power at high RPM. The internals in those engines are small and very light, allowing them to move at much higher speeds. It's really an apples to oranges comparison and each type of engine will shine in different uses.

[noseoil]

To take the 9L vs. V12 analogy a step further... Picture a single cylinder diesel putting along and making lots of torque, vs. a swarm of RC engines chained together to equal the same displacement.

+1 for the Nissan GTR. I'd settle for the bone-stock version making 545 hp. It will still walk all over most current muscle cars & it's just a V6.

[Evil D]

To take the 9L vs. V12 analogy a step further... Picture a single cylinder diesel putting along and making lots of torque, vs. a swarm of RC engines chained together to equal the same displacement.

+1 for the Nissan GTR. I'd settle for the bone-stock version making 545 hp. It will still walk all over most current muscle cars & it's just a V6.

To be clear, it's just a twin turbo V6

As the argument always goes, take any of those V8s and throw two turbos on it and see what happens.

[victorf]

What are some of the notable differences between the two as far as road performance goes, and, which do you prefer?

If you could have any custom-built sports car, muscle car, or roadster, with money and cost as no object, which would you go for?

Many factors involved. To narrow it down, in general, larger displacement works less hard.

To keep up, smaller displacement motor has to basically resorts to more extensive mods to reach similar performance. But then, smaller motor has to give up dependability, since it has tuned close to the edge of its life to get there and along the shorter lifespan, require more maintenance, along with frequent expensive parts replacement.

IMO, it is better to start with as large a motor as one can afford, then stick with basic Hotrod 101, do the intake and exhaust and call it a day. Resist what most gear heads call mods that require touching oil, like getting more aggressive, require opening engine to install cams and such. Which certainly will violate the original engineering design perimeter - so goes the relatively trouble free ownership.

Example of my ride, with some simple intake, headers, followed with a tune to capitalize and homemade parts to enhance conservative basic performance gain:





On a 6 speed over drive gear box, designed for large motor to bypass the gas guzzler tax. Bypassed the two top over drive gears, basically useless in terms of acceleration. Without modifying motor internals for more HP for acceleration, by simple swap of rear end gear ratio for quicker acceleration without motor longevity issues, gas mileage or drastic top end speed loss:









In addition, upgrade brake and suspension components should have been done first, before everything.

These formula provides an economical and reliable package for road course or stop light to stop light dominance. Guarantee a smile on the driver's face.

Aloha!

[SuckSqueezeBangBlow]

Depends what makes you smile, depends if you like to tinker or have it tinkered for you, depends if you want people to look at you with envy or look surprised after you've blown them away.

I'm a car enthusiast. I have just as much appreciation for a muscle car, hot rod, classic, 4x4 or even a type-R Honda. All cars are a compromise. Some can be fun at 5km/h, some are only exciting once over 150km/h, some steer really well, some push you back so hard you think the seat will break.

It's not a question of v6 or v8, but which car ticks the most boxes at the right price in what season of life you are in.

Right now I have a Ford Falcon xr6 turbo. It's a 4 litre inline 6 with a factory gt3540 turbo.
When we bought it we needed a family car with lots of room but I still wanted to have fun when by myself. With only injectors, cat, intercooler with tune it makes approximately 400hp at wheels and hits 100km/hr in 4.7 s.

[Blerv]

It's all a factor of cubic inches assuming everything else is the same. You could have have a 5 liter/302 cubic inch V2 which should have similar properties. Problem being the Pistons would be the size of Folgers coffee cans and the loping idle would shake the car horribly. Tiny numerous cylinders of the same displacement are inherently more smooth. It's also more service to perform and in theory more crankshaft/bearing strain due to the length needed to accommodate all those pistons.

Like the question of Spyderco locks though application is everything. With the exception to maybe the Nissan GT-R, Acura NSX and a couple Audi motors V6's are entry level engines (if not 4cyl) and bigger V8's are "premium" motors.

That said, with CAFE restrictions on averaging a companies fleet MPG I fear the V8's (and other massive engines) are becoming extinct. Right or wrong smaller turbo motors are able to sustain higher average and light-throttle MPG's.

If you want a V8, get it while you can. At least on the new car market.

[defenestrate]

Through owning and driving of Cherokees and F150s I've come to very much appreciate the inline 6. The ones I've driven are really better about a wide torque band that becomes available at rather low RPMs whereas many of the equivalent V6 and V8 engines produce more top-end power. I understand there is a pretty healthy line of high performance Ford straight 6s in Australia that are raced.

[The Deacon]

Funny thing, of all the cars I've ever driven, the four that were the most pure fun to drive were an MG-TD, MGA, Morgan +4, and BMW Z-3. Quite a few years separate the last one from the others, but all of them had relatively small displacement four cylinder engines. If money were no object, I'd find myself a fully restored MG-TC or TD as a play thing. As things stand, for the last year or so I've been toying with the idea of picking up a used Z-3 as a second (or perhaps second childhood) car.

[victorf]

Depends what makes you smile, depends if you like to tinker or have it tinkered for you, depends if you want people to look at you with envy or look surprised after you've blown them away.

I'm a car enthusiast. I have just as much appreciation for a muscle car, hot rod, classic, 4x4 or even a type-R Honda. All cars are a compromise. Some can be fun at 5km/h, some are only exciting once over 150km/h, some steer really well, some push you back so hard you think the seat will break.

It's not a question of v6 or v8, but which car ticks the most boxes at the right price in what season of life you are in.

Right now I have a Ford Falcon xr6 turbo. It's a 4 litre inline 6 with a factory gt3540 turbo.
When we bought it we needed a family car with lots of room but I still wanted to have fun when by myself. With only injectors, cat, intercooler with tune it makes approximately 400hp at wheels and hits 100km/hr in 4.7 s.

Can't agree more!

Unless we can have back to back comparisons, not many of us are having the fortune as Jay Leno owning a fleet.

Although, I wouldn't remake any of my past projects. My past projects belonged in the past, I enjoyed them for what it was worth, learned and eventually, bored with them. Even my present ride will one day, in the past. One thing I reap from these steady change is - I ended up a better tinkerer.

Automotive performance is among many fronts which Down Under is known.

I enjoy using EFILive tuning software. As well as the excellent Australian made DBA two piece rotors:



Not Tail of the Dragon, but this locally famed twisty - Snake Road - demands the reasonable able suspension components, to compliment for a speedy thrill, when demanded, on my ride. This road, both sides, are dotted with many permanent monuments, testament in remembrance, of those before, had failed.

The beginning:



1/3 way down, too much slow traffic, aborted drive, waiting an opening to turn back:



Homeward bound. Back to opposite from where I started:



Some pictures on your swift Ford Falcon to share would be great!

Aloha!

[bdblue]

It's all a factor of cubic inches assuming everything else is the same.

Yes so the V6 will normally be at a disadvantage. It is unreasonable to build a V6 with displacement similar to V8's, the V8 will be better.

When I was growing up most domestic cars were inline 4's or V8's. The inline 6's were almost never tuned for performance so they were dull by comparison. V6 engines were more common in imports but since then they have become more popular for domestic vehicles. I once owned a 3.0L 220hp Yamaha engine in the Taurus SHO. It was a nice engine but did could not achieve its performance potential as built and there were not enough of them for proper aftermarket support. Fast forward to now and all 3 domestic manufacturers have V6 engines of about 3.6L and 300hp. They went from 73hp/liter to about 84hp/liter by improving valve timing. Now turbocharge those things to within an inch of their lives and you can get much higher output. Of course you can do the same thing with the V8. In street trim Nelson racing engines gets 1500hp out of common size V8 engines and turbocharged race cars get 2000hp out of domestic V8's.

One thing that I seem to have observed is that small engines can achieve more horsepower per displacement than larger engines. This might be due to being capable of higher rpm. This would point to a V12 of given displacement being capable of more power than a V8 of the same displacement, the V8 being capable of more power than a V6 of the same displacement. There is overlap in engine sizes- what comes to mind are Ferrari V12 street engines of relatively low displacement and I seem to recall BMW making fairly small V8 engines for street use. I think it is unfair to compare a turbo V6 with a N/A V8. "assuming everything else is the same", I think the engine with more cylinders of less displacement each will have the edge.

[SuckSqueezeBangBlow]

at Mt. Panorama (Bathurst)






Australia has a good car scene, and has made and continues to make (only just) some pretty good stuff, considering our relatively tiny population of 23 million.

My previous project car. '74 Corolla which received a 4age turbo

[Blerv]

Your SHO was a great example or an engine built before its time. It had more new tech and exotic components than almost any other engine in the 80's. The main problem was finding a suitable host and the Taurus was a process of elimination choice. Almost two decades later Honda and Nissan were only slightly able to build a better performance V6. These days I would argue it is possible to compare turbo to NA as reliability isn't an issue (relative to high redline/compression NA) and torque curves are reasonable. They aren't on-off switches with scary lag.

These days car makers can almost do anything they want regardless of construction. From 100hp/liter normally aspirated to far more than that turbocharged. Even without fully electronic actuated valve train (ie still using cams) they can still play with overlap and ignition timing. Once they go full electronic valvetrain or ditch fossil fuel combustion all together the performance ceiling will skyrocket.

One thing that won't bode well for the future is the visceral sounds of exotic v-engines. Some of this can be matched in header and exhaust design but making a 1.6-2.5L four cylinder sound "fancy" is nigh-impossible. Maybe with ITBB's at 9,000 rpm but it's still not the same as a Ferrari. Electric will be further interesting. Maybe the electronic whine of single-gear transmissions will be the new crescendo? :)

[victorf]

at Mt. Panorama (Bathurst)






Australia has a good car scene, and has made and continues to make (only just) some pretty good stuff, considering our relatively tiny population of 23 million.

My previous project car. '74 Corolla which received a 4age turbo

Thank you for the race pictures. Any on your engine layout?

Your '74 Corolla reminded me when I had my massaged 320i with full on Alpina Suspension. But smoked by a tubo Corolla in every which way. Lesson learned.

Aloha!

[victorf]

Your SHO was a great example or an engine built before its time. It had more new tech and exotic components than almost any other engine in the 80's. The main problem was finding a suitable host and the Taurus was a process of elimination choice. Almost two decades later Honda and Nissan were only slightly able to build a better performance V6. These days I would argue it is possible to compare turbo to NA as reliability isn't an issue (relative to high redline/compression NA) and torque curves are reasonable. They aren't on-off switches with scary lag.

These days car makers can almost do anything they want regardless of construction. From 100hp/liter normally aspirated to far more than that turbocharged. Even without fully electronic actuated valve train (ie still using cams) they can still play with overlap and ignition timing. Once they go full electronic valvetrain or ditch fossil fuel combustion all together the performance ceiling will skyrocket.

One thing that won't bode well for the future is the visceral sounds of exotic v-engines. Some of this can be matched in header and exhaust design but making a 1.6-2.5L four cylinder sound "fancy" is nigh-impossible. Maybe with ITBB's at 9,000 rpm but it's still not the same as a Ferrari. Electric will be further interesting. Maybe the electronic whine of single-gear transmissions will be the new crescendo? :)

No truer observations!

Ever heard the shriek exhaust from a statement of a car - dared to compare among all the established exotics, all could be had, when introduced, for under $400 K, built by Toyota - Lexus LFA?

Aloha!