I-6 vs. V6

[jon_570]

why did toyota do an inline 6 instead of a V6 in the supra??the i6 IMO would be easier to work on

[bgrieger]

The I6 was a tried and true engine for them, and embodied the smoothness they demanded for the platform.

V6 engines are more prone to vibration, it was cheaper to stroke the 5M inline motor than to design a whole new V6 for the platform, it is easier to turbocharge an inline engine based on configuration. Lots of reasons. Not the least of which, I find the inline engine to be easier to work on. Everything is more logical in it's placement, and the same parts are in the same location for easier access (ie one fuel rail, one intake manifold, one exhaust manifold, one exhaust header etc.) V engines I find a PITA as the shock towers are always in the way of getting to half the engine...check out the engine bay of the V6 Nissan 300ZX for a view of how bad it could be!

[supra saiyan]

A V6 would fit in a smaller space than an I6, but that's about the only adavantage I see. I6 engines are easier to turbo charge, and just easier to work on in my opinion as well. I have also read that I6 engines accelerate smoother and deliver power better than a V6 would.

[s3v3rth3stars]

i6 engines usually have more main journals and therefore more places to hold down the cranshaft and brace against harmonic vibrations. i6 engines also run way smoother than v6 engines and due to the increased stuctural strength associated with more main journals can make more power safer. thats why skylines and supras can make well over 900hp on the stock bottoms, try that on a grand national or even a corvette 350. even if they could make the power they probably would last as long as an i6. and i am not 100% sure but the firing orders are friendlier to the rotating assembly

[Toysrme]

I6 easier to work on? Tell that to any IS/GS/SC owner I know. They're no easier to work on any a transverse v6 (With the hidden rear manifold) and *not* as easy to work on as a longitudnial v6. v6's are smooth from Toyota. Toyota uses a boatload of vibration dampeners. Between 5 & 9 counterweights depending on the engine. They are noteably smoothe running & fire 1-2-3-4-5-6 except for a short three year run 94-96 1mz-fe's. (Mistake)
The benifits to a v6 are:

• Light weight. The current 2gr-fe weighs 359lbs, makes 272bhp, the 2gr-fse makes 306bhp, weighs 396lbs. They share the top all-time records for weight to horsepower ratio by a WIDE margin with the *brand* new 1ur-fe v8 (which is massive, 520lbs, 380bhp) No other Toy engines are within 10%, very few within 15% (The fabled 2jz-gte isn't even in the ballpark stock.)
• To go with weight, v6's have lessrecipricating mass to begin with. Their accelleration rate is just flat out faster than an equivilant i6. You are sacrificing nothing to get a free edge in an aspect of performance (Remember that there are three parts to power. Power VS rpm, Power vs time, Power vs MPH.)
• Less expencive to produce
• They are less than 2/3 the overall length
• Blah blah blah you always hear about valvetrain problems at high rpm. Even 80's Toy engines were spinning near 7000rpm stock all day happy as a lark...

The reason that minus the 1fz-fe Toyota has phased out i6's (And it's getting replaced soon...), is because they just flat out have do not any benifit over a v6 at this point & time. Basically... They can make a v6 a better engine than the i6's ever were without any of the drawbacks. The i6 has passed it's prime. You'll see it in the diesel world, but that's about it. Their use has been declining for a long period of time.

So I'm sorry, but from an engineering & marketing stand point. You'll just have to get over it. They aint coming back with a new one. No reason in the world to do it.

thats why skylines and supras can make well over 900hp on the stock

What the actual bottom ends? If you can do it in a VQ, or a Mitshit.... A VZ MZ or GR could do it too.
Look at Gadget @ UDR. He had a truck 5vz-fe putting out 850 4*4 horsepower with pistons & rods...
I hate to tell you, but the i6's are nothing special. The same time span v6's stack up perfectly well to anything without forged pistons <cough> 2jz-gte <cough>. The only reason the 2jz-gte is able to make horsepower above any Toyota engine short of an early 1uz-fe v8 else is because they're dyno queens with nice factory pistons. Short of that...... They're no better than any Toyota v6 or v8 produced (respectively) after 1991 or 1989.

[bgrieger]

Actually, the question was why they didn't use it in the supra...15 years of design advances will clearly change the equasion. Compared to anything Toyota used in the 80s and early 90's, the V configuration engines were not going to give the cars what was demanded...ultra luxo smooth power. Not to say they are the kings of the hill anymore, as packaging is too tight to fit their long arses in anything anymore. IS owners everywhere will agree...but in that mousehole excuse for an engine bay, even a V6 would have been a nightmare...more about the car than the engine for ease of working on it.

Originally Posted by Toysrme

v6's are smooth from Toyota. Toyota uses a boatload of vibration dampeners.

Yep, they are fairly smooth now. Inline engines are still smoother. The nature of only moving pistons on one plane is the key. Sure counterbalances help, but they are still not as good in this regard.

Originally Posted by Toysrme

The benifits to a v6 are:
[*]Light weight. The current 2gr-fe weighs 359lbs, makes 272bhp, the 2gr-fse makes 306bhp, weighs 396lbs. They share the top all-time records for weight to horsepower ratio by a WIDE margin with the *brand* new 1ur-fe v8 (which is massive, 520lbs, 380bhp) No other Toy engines are within 10%, very few within 15% (The fabled 2jz-gte isn't even in the ballpark stock.)

Sure, cast iron blocks will do that. An aluminium 2J would clearly have competed. Again, a decade or better of engine design later...

Originally Posted by Toysrme

[*]To go with weight, v6's have lessrecipricating mass to begin with. Their accelleration rate is just flat out faster than an equivilant i6. You are sacrificing nothing to get a free edge in an aspect of performance (Remember that there are three parts to power. Power VS rpm, Power vs time, Power vs MPH.)

shorter crank, that's about it. you save a couple of lbs at the very centre of the rotating mass, so you save it at the point it makes the least difference. Add the counterweights of a V that are not at the centre of the mass on and as a rotating assembly, I'd suggest that you split the difference.

Originally Posted by Toysrme

[*]Less expencive to produce

I can't see how...V engines require a lot more individual component casting and more complex machining.

Originally Posted by Toysrme

[*]They are less than 2/3 the overall length[*]Blah blah blah you always hear about valvetrain problems at high rpm. Even 80's Toy engines were spinning near 7000rpm stock all day happy as a lark...

dimensions...we have a winner as to why an inline is no longer used. I've never heard a valve train argument before...that comes down to springs and whether you are on pushrods or OHC, not V or inline...though timing is a larger consideration on a V as you have to time 2 sets of valves.

Originally Posted by Toysrme

The reason that minus the 1fz-fe Toyota has phased out i6's (And it's getting replaced soon...), is because they just flat out have do not any benifit over a v6 at this point & time. Basically... They can make a v6 a better engine than the i6's ever were without any of the drawbacks. The i6 has passed it's prime. You'll see it in the diesel world, but that's about it. Their use has been declining for a long period of time.

Sort of...it fits the packages better, and nobody wants to design a new engine that does not fit. Automakers everywhere have been rationalizing engines for years down to only one or 2 different configurations. The V's are the only things they can get to fit all the cars, so the inlines died. They are hardly inferior, they just don't make economic sense to use in one or 2 cars anymore.

Originally Posted by Toysrme

So I'm sorry, but from an engineering & marketing stand point. You'll just have to get over it. They aint coming back with a new one. No reason in the world to do it.

Drop the engineering part and you have it. It is all about marketing the desing of the car...and the accountants decided on the engine before any of them had a say.

Originally Posted by Toysrme

I hate to tell you, but the i6's are nothing special. The same time span v6's stack up perfectly well to anything without forged pistons <cough> 2jz-gte <cough>. The only reason the 2jz-gte is able to make horsepower above any Toyota engine short of an early 1uz-fe v8 else is because they're dyno queens with nice factory pistons. Short of that...... They're no better than any Toyota v6 or v8 produced (respectively) after 1991 or 1989.

Here here!

[TTercel]

I have to say I love inline motors. Everyone i have been driven in or have driven rode nice. From Jeep Grand Cheerokee to IS300. Keep in mine everyone BMW still uses I6s and i dont think there planing to change. Tecnically inline motors are better than V motors. But with todays technology there almost the same.

[Jeeves]

Originally they were favored by Jeep because they generated higher (on average) torque than a comparable V6.

[Toysrme]

Originally Posted by bgrieger

shorter crank, that's about it. you save a couple of lbs at the very centre of the rotating mass, so you save it at the point it makes the least difference. Add the counterweights of a V that are not at the centre of the mass on and as a rotating assembly, I'd suggest that you split the difference.

I'm guessing you've never seen the twelve counterweights on a JZ crankshaft LoL!

[TheOtherCarolla]

I-6 less crank vibration, their tride and true (just look at 60s and 70s domestic cars with slant/inline 6's, they still run with 300k on them. Also, more girth in the crank means more rotational mass, more torque.

[supra saiyan]

Quote:
Originally Posted by Toysrme
I hate to tell you, but the i6's are nothing special. The same time span v6's stack up perfectly well to anything without forged pistons <cough> 2jz-gte <cough>. The only reason the 2jz-gte is able to make horsepower above any Toyota engine short of an early 1uz-fe v8 else is because they're dyno queens with nice factory pistons. Short of that...... They're no better than any Toyota v6 or v8 produced (respectively) after 1991 or 1989.
The 2JZGTE actually didn't come with forged pistons. Now, are you telling me that I could take my wife's 94 V6 Camry and keep building around it without touching the internals and make over 500 reliable whp without the motor ever breaking, let alone the 900whp a stock 2JZ bottom end is capable of? Hard to believe that the V6 or V8 of any Toyota from the 90's has the same high performance potential as the 2JZ. Bottom line is that Toyota engineers with more knowledge than all of us combined have had this argument for over 4 generations of Supras, and yet they always used an inline 6. If they had a V6 or V8 that was cheaper to make, lighter, and as capable to put into their flagship car, why didn't they?

12 counterweights is actually a good thing, I'd take a balanced crank anyday over one that needs extra restraints or external balancers, overall just better reliability. Another pro is the I6 allowed for 7 massive main journals, which would've been limited to 5 on a V6, resulting in a block almost immune to flexing that high powered V6 engines are prone to. The block internals are so balanced that they could actually hold up to 8500rpm stock, I've never heard of any V6 engine revving as well as an inline 6. At least not in the 90's.

[bgrieger]

Originally Posted by Toysrme

I'm guessing you've never seen the twelve counterweights on a JZ crankshaft LoL!

Seen it, sure. The JZ is a tough engine to keep coming back to however, as Toyota engineering had so many possible parameters in mind with that design that we have never really known. A 600+ HP capable block, 7500+ RPM capable out of the box. If I was designing for the stratosphere I'd ensure everything was perfectly balanced too. Did it need all that to be to run smoothly in the regions of more mortal engines...no. Take a peek at an earlier M series. They're only partially counterbalanced and still smooth. I wouldn't try visiting too high an RPM with it...

As said before...design and accountants determine engine choice. The bean counters only let the designers have one or 2 basic engines anymore, and designers need to fit them under the ever shortening hood. Hence the V wins.

[touringcamry]

The 2GR V6 reduces cost because that one engine can be used across a large number of cars where using a I6 is not feasilbe. The 2GR will fit in FWD cars such as Camry, Avalon, and RAV 4. The next Sienna will probably also adopt the engine. This engine can also be adopted for use in the Lexus RWD cars, IS350 and GS350.

This saves design cost because they only need to design that one 2GR rather than two or three engines to put in all these cars. Additionally, they are also able to make the 1GR which is used on Tacoma, 4 Runner, and FJ Cruiser.

[Shafto]

V's are just plain gay. lol. haha dont flame guys I like V's but the inline is just a better revving engine and I like rpm!!! I like Japan V's when they want to make a real one. F1 V's are amazing. But when it comes to road cars man the Inlines are just something else.

[TTercel]

Here's a question for you V guys if V's are so good why dont they make V4's instead of inline 4s?