Anything special about I-6 engines? (Volvo,BMW...)

[randomhero439]

Originally Posted By: OVERKILL
Originally Posted By: randomhero439
Originally Posted By: dparm
Go drive the Audi 3.0TFSI, Nissan VQ, etc and you'll see that a modern V6 is almost indistinguishable from an I6.

Just my opinion, but the I6 advantages aren't that huge these days.


Honda V6 comes to mind... none VCM of course

Here is some smooth power/torque delivery any I6 owner will be jealous of. The blue line is the most recent dyno of my 3.0L Honda V6


Why would they be jealous

E46 330i and 330i ZHP:

And that's not even mentioning the M3.... (of course now I've mentioned it.... LOL!)


Ok... tu shay

 

[Win]

The I6 and V12 configurations are inherently balanced, as previously noted. If you like to DIY, an inline engine is much, much, easier to wrench on than a vee type engine.

I'm pleased with the two modern V6's that I own, but, given a choice, I would have preferred an I6.

The misery of wrong wheel drive probably has much to do with the demise of the I6 - it doesn't lend itself well to transverse econobox applications. The little Suzuki with the transverse I6 is the only fwd application that I can think of.

 

[rslifkin]

Originally Posted By: Win
The little Suzuki with the transverse I6 is the only fwd application that I can think of.


Volvo has done a few transverse I6s in S80s. I'm pretty sure those are the only other ones though.

 

[BMWTurboDzl]

Originally Posted By: OVERKILL
Originally Posted By: randomhero439
Originally Posted By: dparm
Go drive the Audi 3.0TFSI, Nissan VQ, etc and you'll see that a modern V6 is almost indistinguishable from an I6.

Just my opinion, but the I6 advantages aren't that huge these days.


Honda V6 comes to mind... none VCM of course

Here is some smooth power/torque delivery any I6 owner will be jealous of. The blue line is the most recent dyno of my 3.0L Honda V6


Why would they be jealous

E46 330i and 330i ZHP:

And that's not even mentioning the M3.... (of course now I've mentioned it.... LOL!)


OT but has the ZHP community ever nailed down the 4k rpm blip? I had a ZHP and can't say I noticed it.

 

[CBR.worm]

I believe Volvo and Audi also had some transverse I 5's

 

[glock19]

Originally Posted By: CBR.worm
I believe Volvo and Audi also had some transverse I 5's


My 2001 S60 had a transverse I5. It wasn't too big on torque but it was buttery smooth.

My parents still have that car and it's running strong at 140K.

 

[hattaresguy]

I prefer a straight 6 very easy to work on and lots of torque.

Now BMW is the last company to really use straight 6's, Mercedes dumped them in the 90's which was a mistake.

 

[Mykl]

Originally Posted By: hattaresguy
I prefer a straight 6 very easy to work on and lots of torque.

Now BMW is the last company to really use straight 6's, Mercedes dumped them in the 90's which was a mistake.



....and sadly they seem to be in the process of dumping them now.

 

[gofast182]

Originally Posted By: OVERKILL
Originally Posted By: randomhero439
Originally Posted By: dparm
Go drive the Audi 3.0TFSI, Nissan VQ, etc and you'll see that a modern V6 is almost indistinguishable from an I6.

Just my opinion, but the I6 advantages aren't that huge these days.


Honda V6 comes to mind... none VCM of course

Here is some smooth power/torque delivery any I6 owner will be jealous of. The blue line is the most recent dyno of my 3.0L Honda V6


Why would they be jealous

E46 330i and 330i ZHP:

And that's not even mentioning the M3.... (of course now I've mentioned it.... LOL!)

I don't think they would be jealous but they sure aren't feeling as good knowing that J30 V6 is as silky smooth as they come, it's very potent, and will run for a ton of miles...then again the J series powers a different set of wheels than the BMW mills do...so while they might like a J series under the hood they'd never give up the great chassis for it.

 

[OVERKILL]

Originally Posted By: gofast182
Originally Posted By: OVERKILL
Originally Posted By: randomhero439
Originally Posted By: dparm
Go drive the Audi 3.0TFSI, Nissan VQ, etc and you'll see that a modern V6 is almost indistinguishable from an I6.

Just my opinion, but the I6 advantages aren't that huge these days.


Honda V6 comes to mind... none VCM of course

Here is some smooth power/torque delivery any I6 owner will be jealous of. The blue line is the most recent dyno of my 3.0L Honda V6


Why would they be jealous

E46 330i and 330i ZHP:

And that's not even mentioning the M3.... (of course now I've mentioned it.... LOL!)

I don't think they would be jealous but they sure aren't feeling as good knowing that J30 V6 is as silky smooth as they come, it's very potent, and will run for a ton of miles...then again the J series powers a different set of wheels than the BMW mills do...so while they might like a J series under the hood they'd never give up the great chassis for it.


Having driven several I6 BMW's and the Honda V6 in question, I'll say that the I6 is the smoother engine. And having that perfect natural balance that an I6 has, that only makes sense. Note that this isn't meant to be taken as a knock on Honda's V6, I think it is an excellent engine. But the natural balance that an I6, V12...etc have make them smoother by default.

 

[CBR.worm]

I like the I6, but the reality is that there are many very smooth implementations of V6's as well. Personally I don't care for the sound of either, but I prefer the sound of a high revving V6 to an I6. Both sound better than a 4cylinder - unless it can rev to 14k.

I will pay a premium in gas and initial cost for the sound of a healthy V8

 

[440Magnum]

Originally Posted By: gofast182
so while they might like a J series under the hood they'd never give up the great chassis for it.


They wouldn't take the J series under the hood regardless of the chassis. Its certainly a good engine, but its nowhere near a BMW I6. Not even the same zipcode. Saying its 'silky smooth as they come' is just flat untrue. It is a v6 THEREFORE it cannot be as smooth as an I6 without power-robbing balance shafts and the aid of carefully designed engine mounts. And even with those features to isolate the vibration from the driver, the higher order imbalance stresses are still there internal to the block, even if they're being canceled out by the balance shafts. That fact is down to physics, its not really subjective.

The same is true with inline 4s, you can make the driving experience tolerable with balance shafts, but the higher-order imbalance stresses are always there transferred from the crank to the block and thence to the balance shafts that cancel the external vibrations out. That's why American v8's are "twisted crank" designs with the throws offset 90 degrees from each other and big counterweights instead of "flat crank" designs (ala Ferarri) with smaller weights, 180-degree throw offset, and a lighter crankshaft. Flat-crank v8s have the higher-order imbalance of two I4 engines grafted together at a 90-degree angle- basically trying to hop up and down along the two cylinder bore axes twice per bank per crank rotation. (A long-winded way to say flat crank v8s shake your fillings out). Ferrari and others tolerate the vibration for lower rotating mass and quicker throttle response, American (and most German) v8 designs choose the heavier crank and bigger rotating mass for the better overall balance... which is still less perfect than the I6, by the way.

 

[blackman777]

The Suzuki Verona seems like a "cheap" way to try-out an I6 and see if they are really any better than a V6, I4, or I3.

 

[KenO]

Agreed on almost everything above. The only downfall of the I6 is the long crankshaft. As long as they are, they need to be treated as a flexible rotor re: balancing & harmonics. The only BMW I6's that can safely rev much higher than ~7200 or so rpm are the Motorsports engines, like the S38 & the S54. Ever noticed the S54 has a massive TV damper, with 4 big M12 bolts holding it to the crank, vs the 1 main bolt on most other cranks, including most other BMW cranks? Revving a long crank so high creates massive harmonics issues, and they will shake the motor to death once they hit that upper harmonic frequency. On S52's with lightweight crank pulleys (replacing the TV damper altogether for some ignoant reason), or people just trying to rev them too high (seems ~7400-7500 rpm or so on the S52, hence the mass of failures for the people who bought Sunbelts cams - that made power way up that high) I've seen snapped crankshafts, snapped oil pump drives, oil pump nuts backed off completly, etc. The Grand Am teams running S54's all ran infrared temp sensors on the TV dampers because of so high they were revving them as well. They had a temp theshold, and if that was ever reached, the TV dampers were removed and discarded immediately. It wasn't uncommon to lose a motor from a failed TV damper.


However, keep it below that threshold, like 99.8% of them are, and they're amazing, wonderfully sounding, long lasting engines.

 

[hattaresguy]

http://editorial.autos.msn.com/blogs/autosblogpost.aspx?post=ed9a40d9-bd79-4257-b243-275fd6eb5068

Spoke to soon, looks like their are rumblings of a new line of I6's in Stuttgart.

 

[Spazdog]

Originally Posted By: bepperb
The only thing better about a v6 is that it's narrow enough to be mounted transversely on a front or all wheel drive car. It's worse from a NVH standpoint and in OHC applications comes with twice as many moving parts in the valvetrain plus a ridiculously long belt/chain.

There's a reason in applications that an I6 fits (like a rwd truck/ semi tractor/school bus) that's what's in it.


Mercedes Benz used a 90° V6

It was a pretty smooth engine. Still managed to make competitive horsepower in spite of having to power a counter rotating balancer. But it negated the narrowness of the usual 60° V6.

 

[Lyman]

Many years ago I had a 57 Chevy truck with a 235 I6 I ran a Clifford Research intake with a small 4bbl and split header into duals. It was a great running truck. I was 18 years old at the time and now at 50 I would love to have it back.

 

[Merkava_4]

The Toyota I-6 sure is a beautiful running engine -- smooth and torquey.

 

[blackman777]

Thought the Toyota I6s were unreliable?

 

[meep]

^^^ Not that I ever heard. built like tanks. Looked a lot like a benz motor on the inside. They probably would fly apart if over-revved... they were kinda like jeep 4.0s in that they had loads of torque but didn't do much up high.

I just helped a bud pull an I6 from a '90 FJ60. IIRC the factory tach redlined at 4500.

I had a buddy in HS that drove a straight-6 cressida. He was an awful driver and used the gas pedal as a toggle switch. on. or off. drifted every intersection for YEARS. he destroyed that I6, but it took 196,000 miles to do it IIRC. Dropped another one in. car fell apart around the second engine.