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nasco
10-14-2018, 06:36 PM
Greetings fellow members of the forum, after a rather longer than preferred hiatus from the forum I have returned. This time with a question that will help me formulate the next steps in my "Build" which too has taken a hiatus. I am now getting ready to have my car tuned by DUDMD as I have acquired most of the parts required for it. From what I have seen the following is required to get the full amount of power extracted from his Stage 3 tune.

-4" MAF Housing (arriving in the mail next week)
-Cold Air Intake (I've had the Dinan one on for a little over a year now)
-A larger throttle body (In my case I have the N62 with the converted patch harness but have yet to put it on the car.
-A cat delete (waiting on having the tune done first before I go to sole off-road use :))
-The M62 or M60 Intake manifold(I have an early M60 Manifold laying around with the internal velocity stacks).

After doing a little bit of digging around there are not many dyno charts available for before and afters of having the tune done. Dima has two on his forum post from many moons ago but they appear to have a different dyno used for measuring torque and power. Through what I have found on the forum I have seen a few variances and I am posing this question to get a more solid answer so I can make my decision and have my car tuned. The M60/2 manifolds were made with much wider runners than the M62TU manifold, and thus more peak power is extracted from that manifold. However several members have reported a slight loss in torque below 3000 rpm, and the variance in how bad the loss has been described as barely noticeable all the way to god awful. A decent amount of my driving on a day to day basis is in the 2000-3000RPM Range and that low-end grunt of torque is absolutely fantastic when it comes to merging on the highway without having to drop a couple of gears or even just hauling around at 2500rpm.

I would like to keep as consistent of a torque band as possible and want to know if I go with the M60 manifold vs keeping the M62TU manifold on there will I actually get that loss in torque in the lower mid-range? Is the extra added top end really worth it if I do? Is there a different manifold I should get if I want to keep that torque and get that added extra top end power? I'm a little stuck here and haven't been able to think about it as much as I'd like because muh engineering program is kicking my ass.

Also on a side note, I've seen that the E34 540i/6 FBO tuned by DUDMD has much higher peak numbers than the E39 540i/6 with the M62tu despite having both 10% more displacement and Vanos. Is that actually correct? Something about that doesn't really seem right.

shwy
10-15-2018, 03:05 AM
The M60 manifolds larger runners moves the torque band up the rev range as that is where larger runners provide more benefit. It will become more efficient at making power at higher RPM and less efficient at lower RPM.

With the TU engines, Vanos adjusts the valve timing depending on throttle input/rpm/load eventually advancing cam timing at high rpm to make more power etc which I believe is why the engineers combined it with the thinner runners of the M62TU manifold (which increases efficiency in the lower rev range) theoretically increasing the area under the torque curve throughout the rev range under WOT conditions.

Its of my *OPINION* that the M60 manifold stands to undo some of the engineering and vanos benefits resulting ultimately in less total area under the torque curve(the drawbacks at low rpm outweigh the benefits of the top end). But without back to back dynos who is to say?.

Besides, the intake side of the M62 is really quite good as it is. The real gains will come from the extremely restrictive exhaust manifolds, which if your 540i is going to be off-road, that would definitely be something to consider.

I believe we have a mutual friend with a totaled Topaz blue 540i6 M-sport? correct me if I am wrong haha.

geargrinder
10-15-2018, 09:42 AM
the variance in how bad the loss has been described as barely noticeable all the way to god awful.

As often is the case, neither is correct. Its more than 'barely' but not that bad.

Don't sweat it. The TU still will have that better low/mid-range grunt that the non-VANOS has. Its worth getting back something at the top end IMO, unless youre a driver who says "well I NEVER redline it, I like more torque from a stop..."

What I would say is, don't get TOO bonered up about how many racekarwhorespowerz you're gonna get from all that big intake stuff. The stock M62TU isn't really intake restricted, its exhaust restricted by the MANIFOLDS (aka the cat delete ain't gonna do sh1t except make yer car smelly... unless your cat is dead).

Neither is a tune gonna do a ton for you, although throttle pedal remapping maybe makes it feel better, so... OK could be OK anyway.

I think there's a reason you don't see BTB same-car dyno comparos out there for that setup... cuz it wouldn't be really mega impressive for all the effort... Frankly I wouldn't bother w/ all the 4" stuff - but - since it seems like you're in already, well... go for it.


Also on a side note, I've seen that the E34 540i/6 FBO tuned by DUDMD has much higher peak numbers than the E39 540i/6 with the M62tu despite having both 10% more displacement and Vanos. Is that actually correct? Something about that doesn't really seem right.

Oh yeah that's right. Its primarily about the valvetrain.

Slightly different timing, longer durations in the M60, which is well know to be a somewhat better tuning platform. I think lift is the same but the duration and timing (esp on the exhaust cam, since the VANOS is adjustable obv) is what makes the difference.

If there were aftermarket cams available for the VANOS car, and you could add duration and maybe if you could some lift without notching pistons (you can't), then that woudln't be the case, but... Without opening them up and getting real gnarly, the M60 (and its immediate descendant M62-non-VANOS) have better top-end breathing capability... Pretty well proven... IMO the VANOS motor makes a better street-daily just for the reasons you mention, but the project-car guys usually choose non-VANOS for simplicity and for the cam/valvetrain reasons.

- - - Updated - - -


Its of my *OPINION* that the M60 manifold stands to undo some of the engineering and vanos benefits resulting ultimately in less total area under the torque curve(the drawbacks at low rpm outweigh the benefits of the top end).

Yeah, IMO just shies the other way, but like I said above.. depends on owners driving profile... Especially for an auto-car I might lean "leave it alone" but otherwise... depends on how you drive it...


Besides, the intake side of the M62 is really quite good as it is. The real gains will come from the extremely restrictive exhaust manifolds

Exactly. If Id' seen this first I woulda just quoted it above instead of saying it again...

shwy
10-15-2018, 03:32 PM
Great info GG!
I'd love to do headers myself. But smog makes things complicated and I've never looked into any options that would make power and pass smog. Mostly because I'm happy with the power how it is, but primarily because coilovers and a 6 speed swap would be more cost effective performance for me I feel.

Didn't know about the M60 cam duration. Do you know what the difference is in the Pistons (or elsewhere) on the M60 to allow for that? I've heard the TUB46 exhaust cams fit in the TUB44, wonder how that would perform with headers....

nasco
10-16-2018, 12:56 AM
Thank you for your insight and response.

That is certainly true that we do indeed have a mutual friend that totaled a topaz blue M-Sport.

If the juice is worth the squeeze, I may end up going with A1 Headers or trying to make a set of e-bay headers fit. I know that peak wise the numbers are certainly in favor of the M60 Manifold, I may end up just selling it on E-Bay and just sticking with the TB, MAF Housing, and Cold Air with headers.

nasco
10-18-2018, 09:21 PM
Thank you for your extensive write up, I apologize I didn't reply sooner. I will go ahead and look into headers as a more serious option sooner rather than later. Since it's almost absolutely required to pull the motor for a half easy install I plan to do it just once. I would say I definitely wind out the car a little more often than I did before and Will certainly start doing it more often since I will be doing the 90c thermostat mod. I figure that a larger throttle body and MAF with a tune can't really hurt as there is certainly a lot more power to be had from those two modifications.

purplecty
10-18-2018, 09:50 PM
I am about to do this on my 2000 740i sport. All the talk about the later m60/m62 non vanos intake manifold gains and losses feels inconsistent... I hear you will gain HP at higher RPMs but lose low end torque but why does the x5 4.6is which is a vanos motor use this manifold as the stock intake manifold??? Here is the one I have...

https://www.realoem.com/bmw/enUS/showparts?id=FB93-USA-06-2003-E53-BMW-X5_46is&diagId=11_3343

Here is some additional info as well...

https://www.r3vlimited.com/board/showthread.php?t=274288

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shwy
10-18-2018, 11:09 PM
Discussion intakes gets strongly into the subject of fluid Dynamics. The 4.6is has more displacement which pulls more air, it revs to 6500 (higher than the 4.4) and has different camshaft profiles, it's quite different to the 4.4. Incidentally, the 4.6 makes both peak power and torque at higher RPMs than the 4.4...

There are so many intricacies regarding airflow, air intakes and getting air into the cylinder that without scientific testing it's difficult to draw conclusions. Typically, thinner runners increases air velocity which is important at low engine speeds when there isn't much suction from the cylinder tonavcelerate the drawn in air. At higher RPM, velocity of the air isn't (typically) the limiting factor and the actual volume of the air in the intake takes precedence when making power, hence larger diameter runners. You compromise one way or the other.

The DISA valve is a good example of an attempt to overcome limitations of a static intake by changing the length of the intake runners (length isn't the same as diameter of ofcourse, but it demonstrates principle, short runners are good for high rpm and long for slow engine speeds) Ferrari laferrari has an absurdly complex "infinitely variable intake length" system too.

So no single intake design is perfect. One may outperform another on average (total area under the torque curve on a Dyno graph) but there is always a compromise.

That said, the velocity stacks is quite an interesting addition that I'd LOVE to see results of with the M60b40 manifold on the tub44...

01BMWs
10-20-2018, 07:33 PM
I'm still trying to understand (and make a decision on) leaving the intake stock or changing to the M60 manifold.

When I had my e38 I thought that changing all of it made a difference. I had the Dinan CAI, M60 IM, Dinan stage 2 and transmission software all done at the same time. It felt different (more powerful) when I was downshifting and accelerating at freeway speeds, but I never did any dyno runs before or after. So, I'm not making any claims that there was an actual difference.

Now that I have a 540i, I was planning to do the same thing. I have done a bunch of reading and research on here, and the more I read the more conflicting views on if that M60 change is going to be worth it (power-wise). My driving style is more about freeway overtaking speeds. I was thinking (and more importantly reading) about the s/c installs here as well. It just seems that it all of it is too much of a hassle to finally get working properly (with tune). If it IS worth it (not speaking financially, but enjoyment-wise) why would people on here getting rid of theirs?

edjack
10-21-2018, 12:26 AM
nasco, do this forum a GREAT SERVICE: Do a dyno pull on you car with the stock intake manifold, and then change to the M60 manifold. Rinse and repeat, but make sure the conditions are very close.

Post the results.

JimLev
10-21-2018, 07:57 PM
I've heard the TUB46 exhaust cams fit in the TUB44, wonder how that would perform with headers....

Yes they will fit, but don't start the engine. There isn't enough clearance between the intake valves and the piston.

StRaNgEdAyS
10-21-2018, 08:23 PM
You can of course have the piston pockets enlarged... But how much do you want to spend?

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JimLev
10-21-2018, 10:35 PM
I did a LONG post on the 4.6 cams in a 4.4 maybe 4 years ago. Whiteghost sent me a set of 4.6 cams that I put in a 4.4 that I had on an engine stand. IIRC there was less than 0.3mm of clearance on a cold engine while turning it over by hand.
The 4.4 piston tops had plenty of material to cut the valve pockets another 2-3mm deeper.
As you said, how much $$$ do you want to spend.

geargrinder
10-23-2018, 09:09 AM
As you said, how much $$$ do you want to spend.

And for how much benefit...

I'm SURE the 4.6 cams have a solid benefit, and if one had a motor out and torn down already for rebuild or swapping in, then this project would be great/fine/super - refresh the whole motor... notched pistons, better cams... great!

But for anybody w/ a running car, engine-in... its just way way way way too much work for the results... You'd have to do it 100% DIY too or else it'd be an absolute crusher for labor time... cost you thousands of bux in labor alone to have this done to a running car at a shop... Better spent on blowers & nitrous really... (again - different story if the motor is out of the car already...)

nasco
10-23-2018, 02:41 PM
I really would love to do a before/after on the dyno, but I also have yet to get my BSEE and therefore do not have the funds to throw $300-$400 in the air for the sake of the forum. I've contacted a few places in the south bay that have Dyno's and none of them have any dyno-days coming up. I also don't plan on doing this stuff next weekend, I still need to do all of the work for my EE Degree and these midterms are killing me. :/

R Shaffner
10-23-2018, 03:57 PM
If you're still wondering whether to change to the M60 intake manifold...DO IT! Basically, you'll get the best of both worlds. The part-throttle response of the stock TU in middle rpms is higher. It will be a little less with the M60 manifold. BUT, at full throttle all that great mid-range torque is still there. What you will gain is power above 5,000 rpm.

My longer reaction is in this thread:
https://www.bimmerforums.com/forum/showthread.php?2182831-M62-e39-Intake-Manifold-Swap-M62-TU-1-5-8-quot-to-2-quot-Pre-Vanos-M60-M62-Intake-Manifold/page3

whiteghost1
10-23-2018, 10:58 PM
With a good tune and a proper set of headers read:pricey-er, your low end throttle response/pull will be as good as the M62tu manifold, with all the top end benefits of the M60 mani, at least in my experience. The tune will also gain that extra 300rpm redline whilst still pulling hard and making more noise.

Being that I still run the 5HP24 is the only downside to just bolting on the manifold just on it own. Reason being is if you catch the auto trans “off guard” in the not optimal gear for the situation, and at mid throttle modulation, at lower rpm (around 2100-3200rpm) just before it downshifts, there’s a noticeable lag and flat spot. That’s to me when you notice the negative difference the most between the two manis.

Mannyf540
10-23-2018, 11:04 PM
Mine pulls like a beast, new Vanos seals, new guides, I’ve got the AA tune. No extra rpm...
Autotragic also.

purplecty
10-23-2018, 11:09 PM
Mine pulls like a beast, new Vanos seals, new guides, I’ve got the AA tune. No extra rpm...
Autotragic also.Which intake manifold are you running? Is that all you have with a tune?

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Mannyf540
10-24-2018, 12:19 AM
Which intake manifold are you running? Is that all you have with a tune?

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I’ve got the M60 intake and a Dinan cold air intake. She pulls pretty hard. AA for some reason does not provide higher shift points...

According to AA they remap the Vanos.

purplecty
10-24-2018, 12:23 AM
I’ve got the M60 intake and a Dinan cold air intake. She pulls pretty hard. AA for some reason does not provide higher shift points...

According to AA they remap the Vanos.M60 early with the velocity stacks or the later M60 one?

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Mannyf540
10-24-2018, 12:40 AM
It had the velocity stacks if I recall correctly. The trumpets as I’ve heard them reffered to.

purplecty
10-24-2018, 08:21 AM
It had the velocity stacks if I recall correctly. The trumpets as I’ve heard them reffered to.Like this?https://uploads.tapatalk-cdn.com/20181024/589a901c0f470bff2c428b1a6087a131.jpg

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Mannyf540
10-24-2018, 09:04 AM
Yes sir those are it!!

purplecty
10-24-2018, 09:06 AM
Yes sir those are it!!Ahh ok I got one of these non vanos M62 ones... Worth swapping in for my stock TU one?https://uploads.tapatalk-cdn.com/20181024/f19238e6e04cdbe7e250ab83e8e0af81.jpghttps://uploads.tapatalk-cdn.com/20181024/d8027892999775f7653df07196da9187.jpghttps://uploads.tapatalk-cdn.com/20181024/719c596d5b89c22a04c086e79650b10f.jpg

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Mannyf540
10-24-2018, 05:21 PM
Most definitely. Although it has been a subjective matter...
Have you had your Vanos done? And a tune to match. So you make the most use of the additional air volume afforded. But if your Vanos has not been serviced recently, it may take a while for your car to gain momentum. You also want the tune to match.

From experience it would take a while for the car to gain speed before I serviced the Vanos, I had lost the lower end power range.

Upon servicing the Vanos it has once again recovered its lower end torque.

So it depends on your setup and recent service history... your mileage may vary!

purplecty
10-24-2018, 05:25 PM
Most definitely. Although it has been a subjective matter...
Have you had your Vanos done? And a tune to match. So you make the most use of the additional air volume afforded. But if your Vanos has not been serviced recently, it may take a while for your car to gain momentum. You also want the tune to match.

From experience it would take a while for the car to gain speed before I serviced the Vanos, I had lost the lower end power range.

Upon servicing the Vanos it has once again recovered its lower end torque.

So it depends on your setup and recent service history... your mileage may vary!Guides and vanos were rebuilt 35k miles ago or so. No tune. stock m62tu...

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Mannyf540
10-24-2018, 11:47 PM
Then for sure I’d do it!! Especially since your Vanos has been serviced. Thereafter I’d get a larger housing for your mass air along with a larger the throttle body. The mass air housing you can find on eBay, no need to waste your cash on the Dinan one.

Hopefully someone can chime in where they obtained the larger mass air housing. The throttle body would have to be sourced from Dinan. I don’t know of anyone that makes a larger throttle body other than Dinan. You may also consider the cold air intake, although the OEM set up is adequate to do the job, and you don’t run the risk of water entering your intake, although it’s never been an issue for me. And last but not least get a tune, our local forum member DUMD tuning does a great tume for this setup. I’d had purchased with him if I knew he did them prior to my purchase with AA. He maybe able to shed so light where to source the larger mass air housing.

And perhaps down the line some headers, Super Sprints or our mod Jim get some great headers for a decent price, perhaps he’d be so kind to chime in as well.

purplecty
10-24-2018, 11:57 PM
I have thoughts of the 4inch MAF housing and the 84 inch N62TU TB which is actually the DINAN TB...
https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F26 3159692833

https://www.bimmerforums.com/forum/showthread.php?2292590-N62-4-8L-big-bore-throttlebody-fits-m62tu-engine

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JimLev
10-25-2018, 12:09 AM
I bought long tube headers from Schmiedermann, they were actually made in Italy. Will need to look up the actual manufacture. I have the M62 non tu manifold.
There was a thread a while ago about using a throttle body from a newer bimmer which required the connector to be changer, an easy job.
I got a good deal from the BMW dealer on a Dinan carbon fiber CAI, their larger throttle body, and stage 5 tune. Got a Dinan MAF from a member here.

Just saw your post purplecty, that's the TB.

nasco
10-25-2018, 01:58 AM
So It's been decided, Early M60 manifold, 84mm Throttle Body, 4" MAF Housing, my existing Dinan CAI and some sort of headers. I'll do a before after, after and after with three stages. It'll take a while to get it collected but I figure it's not super time sensitive, anytime will do.

Before (Stock with the Cold Air). After will be M62TU Manifold, 4" MAF Housing, 84mm throttle body, and the existing CAI. After #2 Will be M60 Manifold. After #3 will be Headers because I've never seen 540 dyno's for a header swap either.

I supposedly had my Vanos completely re-done when the Timing Chain Guides were done, but the invoice was written in a really shady way so it doesn't mean Jack to me. I was also eye-balling those Schmiedmann headers myself because I've seen really good dyno numbers from them on the M5. Also Planning on getting an X-Pipe in there and running quad tips (I run a muffler Delete it should fit perfectly) after I get my M-Tech Rear Bumper of course.

JimLev
10-25-2018, 11:58 AM
I had the Schmiedermann headers ceramic coated inside and out. IIRC the headers were $1200 and the ceramic coating was about $350.
These are more difficult to install as the subframe needs to be lowered and the engine jacked up.
Supersprints are individual tubes that plug into the collector, easier install but 2x+ the price.

639326

These aren't plug and play, if you don't weld you'll need to get a shop to make the connection to the main CAT's. The pre-CAT's won't be used. I don't get any codes.
639327

nasco
10-25-2018, 07:16 PM
The welding for the collectors part doesn't sound like that big of a hassle. My neighbor welds and he'll also be the one doing the welding for my X-Pipe.

Dumb question but potentially smart answer.

Wouldn't it be better to buy the schmiedmann headers, cut through them at like maybe 5-6 inches before the collectors and then add V-Band clamps or even just re-weld them once the individual tubes are attached to the engine block? Easier install than the regular schmiedmann and basically the same cost too.

JimLev
10-25-2018, 08:06 PM
Not sure I understand your question.
Are you asking about shortening the collectors? You don't want to do that, it will effect the header performance, see below.
All my welded was done after I installed the headers.
I don't think you'd want to cut the individual tubes, sounds like a PITA job with not much room to re-weld the tubes together.

639343

One other thing, you'll need a reducer (cone) to connect the collector to the exhaust pipe.

639339

When you cut the pipe just before the main CAT you'll find out it's a double wall pipe.
I used a torch and tail pipe expander to open up the inner pipe to match the ID of the outer pipe.
It's stainless so you need heat to soften the metal. After getting it expanded I used a ball peen hammer to finish making the ID completely round.
I did this with the exhaust system on the garage floor.

639340

639341

One last thing.
If you make HARD right hand turns the engine is going to move a little bit which is normal.
One of the pipes will make contact with the steering column flex joint.
You have 2 options, put some washers under the drivers side motor mount to slightly raise the engine or put a small dent in the header tube which won't effect anything.

639342

geargrinder
10-25-2018, 08:39 PM
Ha ha I forgot all about dimpling the runners...

nasco the “Jedders” I.e the headers made by M5Jed as “best of all prior headers” design, have the independent runner setup. They are gorgeous sexy. Think he uses double-layer slipfit? Think vbands per runner would suck for fit and be a hassle to impossible to connect in the tight space.

nasco
10-28-2018, 02:48 PM
GG and JIMLEV, That makes a bit more sense now that I think about it. $1300 for Italian made headers also doesn't sound like an awful price to pay considering the amount of power that ends up opening up.

Do Either of you have videos of your exhaust setup with the headers? I currently am running a full stock exhaust and have deleted the muffler and replaced the Y-Res with a cherry bomb. I'm quite satisfied with the tone currently when the car is not running at full heatsoak(this is when it starts getting screechy). I want to keep the volume where its at (with valves of course) and get a slightly deeper tone and wonder if this is the way to do it. Also, if this is the case, I may end up having my neighbor replicate these headers with titanium and create a full titanium exhaust for me. I think that would be an exciting first to the forum.

JimLev
10-28-2018, 09:31 PM
I'm sure I have a video, just need to find it and post it. I'll see if I can do it tonight after the Sox beat the Dodgers or tomorrow the latest.
Jedders headers are very nice, think they are $4-5K, someone correct me if I'm wrong.
Titanium system would be fabulous buy very expensive.

JimLev
10-29-2018, 09:58 AM
Still looking for a video.
I did find this audio file of me driving around the hood with open headers just after I got everything put back together.
Might be just a bit to loud to pass inspection but the music is intoxicating.
Couldn't directly attach an MP3 file so it's on OneDrive. Might take a few sec to load. Turn up the volume.
https://1drv.ms/u/s!ApkTIzHhyMd5pDYIlO1x_qZY3Vnn

nasco
10-29-2018, 05:25 PM
Is that Open Headers but with those SuperSprint ones? If so, I'm sold and I'm determined to get those on asap.

JimLev
10-29-2018, 07:26 PM
No, they are the ones I bought from Schmeidermann, like I said in post 32.

nasco
10-31-2018, 03:00 PM
the ones I bought from Schmeidermann

Soon I'll be able to say this and I'm really looking forward to it. How much does it add according to ye old butt dyno?

R Shaffner
11-07-2018, 07:53 AM
Still looking for a video.
I did find this audio file of me driving around the hood with open headers just after I got everything put back together.
Might be just a bit to loud to pass inspection but the music is intoxicating.
Couldn't directly attach an MP3 file so it's on OneDrive. Might take a few sec to load. Turn up the volume.
https://1drv.ms/u/s!ApkTIzHhyMd5pDYIlO1x_qZY3Vnn

What a great sound!

Forgive me for being slow to realize this, but our V8's really do sound different from American V8's, don't they? When we're at a stoplight with the windows open, we can tell when a good 'ole less-muffled American V8 pulls up beside us. The sound is unmistakable. Not the same when a BMW or Audi V8 pulls up. (Don't think I've ever heard a loud Mercedes V8.)

Our V8's don't have that rumble at idle. That's fine with me. The sound on Jim's file is perfect to my ears.

It must be the different firing order. V engines typically have uneven firing internals anyway (unlike inline and flat engines). And our cars have a different firing order than American V8's (most if not all, I believe). On ours, the firing of the cylinders doesn't alternate between the left and right banks every time. 2 cylinders on each bank fire consecutively.

And of course, thanks to our ability to speak, our ears are hard-wired to notice little things like that. Like our favorite music, or the sound of loved one's voices -- some sounds we can always identify.

Please excuse me now while I go out for a hard drive...