Take the US L67 out of, say a GTP

then take an overseas L67 out of a VT Commodore


what is the major difference between these two that makes them sound SO much different?

The US one has that classic Pontiac V6 growl like they all have...but the VT sounds like...an inline 6...something like a Supra or a Skyline

exhaust system??

I think exhaust is a majority of the reason, but it is just crazy to listen to some of the videos on YouTube, some of them have the same distinctive sound that mine has, but quite a few have that top end "purr" that you get from the foreign dohc 6 cylinders, but from what I know it is the same engine, we need to get one of their mufflers imported and see if that effects it.

Thanks for pointing that out, my engine has been out long enough I don't remember exactly what is sounds like, but it is easier to re do the exhaust again than it would be to do an engine swap to change the sound, when they can sound like that.

Chris

exhaust.. Not any different than a USDM L67. There are some small differences in the construction of the motor, but the parts are all the same. Holden used them sorta like a "kit motor", the assembled and machined raw parts from over here.

Maybe they rotate the opposite direction down there! LOL

------------------
RickN
White 88GT 5spd
White 85GT Auto
White 99 F250SD 7.3PSD 6spd
1956 Ford 860 Tractor w/ Freeman Loader
20Ft H&H Tilt Bed Trailer

[This message has been edited by RickN (edited 11-13-2009).]

Most I saw on youtube don't sound a lot different than the L67's here in large cars... I'd tend to agree, it's exhaust system variations. Just look how different GTP changes w/ Flowmaster, vs Borla, vs Magnaflow. Based on my experience, i'd say the tone you're looking for is also more likely to come from smaller tubing, versus larger.

Simply having more tailpipe (especially after the muffler) generally makes an engine sound smoother to me. Won't try to be an expert in sound waves, just what I've observed.

so the general consensus is the exhaust system huh? I would have thought it had different heads or something to that effect. I've never head of a muffler changing the sound, maybe enhansing it, or amplifying it...but never a signifigant change in the output sound

Programming differences in the PCM are one thing i'm betting.

For years enabling the australian lean cruise mode was the holy grail.
They don't have the same emission's regs we do.
Never paid attention to much of the differences,or lean cruise though.
I could ask some aussie friends what the differences may be other than the lean cruise if you want.

*sorry,didn't catch the "sound" different part somehow.
Was wondering why everyone was talking about the exhaust.
doh.

[This message has been edited by DefEddie (edited 11-13-2009).]

this is the sound I'm talking about
http://www.youtube.com/watc...evH4&feature=related

they're all calling this the ECOTEC V6...so I think it's a different engine than the L67...


according to Wikipedia, the L67 wasn't offered in the VT or VX Commodore, just the L36 N/A

[This message has been edited by 2Point8FieroGT (edited 11-13-2009).]

quote Originally posted by 2Point8FieroGT: this is the sound I'm talking about http://www.youtube.com/watc...evH4&feature=related they're all calling this the ECOTEC V6...so I think it's a different engine than the L67... according to Wikipedia, the L67 wasn't offered in the VT or VX Commodore, just the L36 N/A

Sounds like my girl freinds Honda.. Not a bad thing. I.m just saying. Its sounds great Dear.

[This message has been edited by billpapps (edited 11-15-2009).]

quote Originally posted by 2Point8FieroGT: this is the sound I'm talking about http://www.youtube.com/watc...evH4&feature=related they're all calling this the ECOTEC V6...so I think it's a different engine than the L67... according to Wikipedia, the L67 wasn't offered in the VT or VX Commodore, just the L36 N/A

they go the supercharged 3800.

the exhuast sounds like a borla system. i heard the same thing on a 3.8L camaro with a dual exhuast and borla XR-1 race mufflers
http://www.youtube.com/watc...n2Ig&feature=channel

Another thing that could effect the sound is the large amount of pipe that a FE car has that a Fiero doesn't.

-T

quote Originally posted by 2Point8FieroGT: this is the sound I'm talking about http://www.youtube.com/watc...evH4&feature=related they're all calling this the ECOTEC V6...so I think it's a different engine than the L67... according to Wikipedia, the L67 wasn't offered in the VT or VX Commodore, just the L36 N/A

Don't listen to Wikipedia for solid advice on squat, remember the Commodore is an Australian car so it's Australian bogans who edit the articles

They call it an Ecotec V6, but it's really just a Series II 3800. The NA 3800s *ARE* different to the USDM part, particularly the intake manifold. The SC, no major difference I can name. The biggest reason for the exhaust difference is the Y-pipe - a Commodore is RWD, and has a long Y-pipe setup, versus the GTP with the short Fieroesque Y-pipe. I can only of course comment on shots of the Y-pipe I've seen around here of course, but on a Commodore at least it's quite a lot longer than the ones I've seen here.

http://en.wikipedia.org/wik...den_Monaro#V2_.2F_VZ

monaro = L67

quote Originally posted by darkhorizon: http://en.wikipedia.org/wik...den_Monaro#V2_.2F_VZ monaro = L67

Indeed, they're not awfully common in the Monaro though - everyone wanted the V8 option

It's the exhaust. The effect can be demonstrated easily in the saxophone series; soprano, alto, tenor, baritone. They all have the same principle in construction, same key configuration but different length and bore of the tubing. The muffler plays a part to, here the mouthpiece used on the saxophone further distinguishes the sound emitted from the horn (metal vs. plastic, facing number, then reed strength). In this case the body of the horn can represent the exhaust tubing length and diameter, and the mouthpiece chioce can represent the muffler.

I happened across a nice write up on exhaust system sound dynamics which included some formulas and examples some time ago but can't find it for the life of me. It was good info because sound is just as important as performance. That said I still can't figure out the 4 cylinder guys magnifying the sound of their harmonyless exhaust note.

Source frequency is typically the most key point to any harmonics frequency. There are ways of doing calculations to see at what range your exhaust will resonate (drone), but other than that you can not really tune the "personality" of the sound.

Whoops

[This message has been edited by TEXASGT (edited 11-20-2009).]

I spent 4 years in my high school band 4 years ago.

That doesn't make me a musical expert, but I'd say that the fundamental frequency isn't that important.
After all, you still get the same Euro-sound from an engine whether it's running at 5000 or 7000 RPM.

It's really the combination of harmonics which give the personality I think.

Musical-type people call the combination of harmonics chords.

I did a little research, it appears the naturally aspirated L67 is referred to as the Ecotec engine, and after listening to the sound clip, I would put my money on the engine in the video being the alloytech V6, also known as the GM 3.6L DOHC engine that some commodore models get and which is probably an option for non standard applications.

I've never met a Commodore owner who would go to the effort of installing an Alloytec into a VX... they'd just get rid of the VX in favour of a VZ

quote Originally posted by Carcenomy: I've never met a Commodore owner who would go to the effort of installing an Alloytec into a VX... they'd just get rid of the VX in favour of a VZ

Never thought anyone would go to that extreme, but maybe as has been the case for many cars the engine is an optional upgrade. Despite the title of the video there is some debate among the commenters as to what it really is. Who knows, it certainly doesn't sound like any 3800 I've ever heard.

Ok just to update this thread... The car in question isn't running a L67. In fact its running a LZ9 or a LX9. I am pretty sure at this point its an LZ9 due to it DOHC sound and high rpms. That would be an awesome motor to boost and play with. Might be a new project in the works.

Doing some research for my soon to be swap... if I can ever make up my mind, dependable L67, fun LQ1, anyway.

Is there someway to achieve close to the sound from that video with an actually L67? in a Fiero I mean.

I'm looking for more of an exotic sound than an american muscle car rumble is why I'm asking.