GTV6 exhaust note vs 75 3.0 vs GTV V6

TFJ100 · May 31, 2011, 09:24:53 PM

Hi guys,

Wonder if I could get your views on exhaust note.

A friend of mine has bought a 75 3.0 to replace his 1986 GTV6, but told me the exhaust note of the 75 is not as good as the GTV6. He has read on a forum that removing the catalytic converter will make it more like the GTV6.

I really love the GTV6 exhaust note - I think that apart from a couple of V8 Maseratis, the Alfa would be the best sounding car I have heard.

I would also like my 2001 GTV V6 to sound more like a GTV6, and my friend would like his 75 to sound more like his old GTV6.

Can anyone say what it is that gives the GTV6 such a lovely note? Engine size (2.5 instead of 3.0), lack of catalytic converter, conventional layout instead of transverse FWD, exhaust manifold length?

Or is it a combination of the above?

Also if there is anything I can do to my 2001 GTV V6 to make it sound like a GTV6?

Thanks
Torben

aggie57 · June 01, 2011, 07:48:18 PM

I can't give you a complete answer but my experience is that if you take a standard 2.5 GTV6 and put a standard 3.0 engine into it with all the same exhaust and so on, then you loose some of that really sweet mid range howl. It's still a nice sound but not quite 'there' like a 2.5.

Storm_X · June 01, 2011, 07:55:36 PM

75 3.0 by far

TFJ100 · June 02, 2011, 12:23:34 PM

Good feedback guys.

I like the "howl" of the 2.5, and it seems what you are saying aggie is that it is the capacity increase that cause the loss of that noise, moreso than any change to front wheel drive. I'll ask for a ride in my friend's 75 3.0 to see for myself but that is definitely what he is saying.

I did drive a 3.2GT recently, and while it didn't have the "howl", it had a nice "burble" which my GTV 3.0 doesn't have. So I'm curious whether that is because of exhaust layout or the engine capacity increase.

Storm - why do you say 75? Or is it bias coming through...

Call me a bit weird, but the engine note is probably the no.1 criteria for me in choosing a car, so long as the hygiene factors are there (reliability, pleasant cabin atmosphere, manual transmission (which works, sorry 116 owners), EFI, power steering, reasonable handling)

shiny_car · June 02, 2011, 03:05:43 PM

The 916 GTV 3.0 lends itself nicely to an exhaust note, with some mods. I definitely think it's the exhaust design that muffles the sound.

A few owner-mates have deleted 2 of the 3 resonators/mufflers in the rear. From this schematic, you retain part '1' and ditch part '12'.

And in this pic, you delete '1' and '2', and keep '3'. So you new exhaust goes from the number '3' muffler then 'straight through' to your tips.

It's also easy to then add a Y-pipe and finish with quad pipes.

This simple mod really enhances the sound of the V6. A friend said he paid under $200 to have a simple Y-pipe and quad tips fitted to his GTV, and it sounds great!

On the 3.2, I'm certain it's the 'CF3' design to meet emissions requirements overseas, that results in a subdued sound. There are cats in the manifolds plus the main cats. Though mods to my GT 3.2 have enhanced the sound, and a mate's 156GTA has a Unicorse rear muffler that sounds superb, if you want the high pitch rasp (and don't mind paying the multi-thousands of dollars just for a rear muffler!).

alfagtv58 · June 02, 2011, 03:51:29 PM

Can't quite put my finger on why, but the 2.5 has it over the 3.0.

Want to listen to the best sounding GTV6 in the world, bar none....IMHO

http://www.alfaclubvic.org.au/forum/index.php?topic=926.0

Even with crappy computer speakers, wow. Imagine what its like driving it!

TFJ100 · June 02, 2011, 05:08:34 PM

Thanks Shiny,

Actually I'm having it done this weekend - John Toomath gave me the idea. He got his done about four years ago, and now inflation has obviously taken hold because Bay Road Exhausts are charging me $400. Apparently it is because I am getting stainless steel tips, not chrome. I am going for mild steel in the piping though due to stainless steel being a bit pricey.

However, I don't think the sound has changed note on John's car though. I believe it has made it a little louder (not much - no drone). Given it is a nice sound anyway, that should be just fine. No "howl" unfortunately.

Your schematic and picture is really helpful though, so thanks for adding it. I presume the cat is in the first muffler?

Torben

Anthony Sharp · June 02, 2011, 07:56:42 PM

Sorry all but there is nothing quite like a V8, I love the sound of Ali's (Vanessa's) GTV6 at full revs on the Reefton Spur, but untill you make a Montreal sing for you your life is not complete, I live in hope of of making T33 sing to my tune one day but until then, I will make every Alfa sing on every drive, as life is always to short.

shiny_car · June 02, 2011, 08:02:58 PM

Quote from: Torben F-J on June 02, 2011, 05:08:34 PMI presume the cat is in the first muffler?

It's further forwards. It sits 'infront' of that muffler '3' in the photo: manifolds > front pipes > cat > muffler '3'.

In the schematic, the cat is the piece that joins onto the beginning of part '1'.

grpa9x · June 02, 2011, 08:57:12 PM

Quote from: alfagtv58 on June 02, 2011, 03:51:29 PM
Can't quite put my finger on why, but the 2.5 has it over the 3.0.

Want to listen to the best sounding GTV6 in the world, bar none....IMHO

http://www.alfaclubvic.org.au/forum/index.php?topic=926.0

Even with crappy computer speakers, wow. Imagine what its like driving it!

yeah i have to agree, this is sensational, and the pilot aint to shabby either

cheers michael

Storm_X · June 03, 2011, 05:56:36 AM

Quote from: Torben F-J on June 02, 2011, 12:23:34 PM
Good feedback guys.

I like the "howl" of the 2.5, and it seems what you are saying aggie is that it is the capacity increase that cause the loss of that noise, moreso than any change to front wheel drive. I'll ask for a ride in my friend's 75 3.0 to see for myself but that is definitely what he is saying.

I did drive a 3.2GT recently, and while it didn't have the "howl", it had a nice "burble" which my GTV 3.0 doesn't have. So I'm curious whether that is because of exhaust layout or the engine capacity increase.

Storm - why do you say 75? Or is it bias coming through...

Call me a bit weird, but the engine note is probably the no.1 criteria for me in choosing a car, so long as the hygiene factors are there (reliability, pleasant cabin atmosphere, manual transmission (which works, sorry 116 owners), EFI, power steering, reasonable handling)

To be honest i have only heard a 3.0 with a exhaust, and from the videos i have seen on you tube a few years back now. Have to watch in the before i have a shower.

This guys having some inappropriate fun in the local car park But i love the sound of it valve bouncing.

My favourite

MD · June 03, 2011, 09:23:38 AM

Personally I think the debate about the growl vs the howl is endless.

Induction sound is realy where it's at.

Ultimately, it's mambo that counts.

aggie57 · June 03, 2011, 09:59:49 AM

Quote from: Anthony Sharp on June 02, 2011, 07:56:42 PM
Sorry all but there is nothing quite like a V8, I love the sound of Ali's (Vanessa's) GTV6 at full revs on the Reefton Spur, but untill you make a Montreal sing for you your life is not complete, I live in hope of of making T33 sing to my tune one day but until then, I will make every Alfa sing on every drive, as life is always to short.

Actually - now that you mention it Anthony I have to agree. I recall your Dad giving me a drive of his Montreal through the Adelaide Hills many years ago. We came up behind a slower car going up a hill and in typical Ray fashion he said "well, what are you waiting for - an invitation" or words to that effect. What a sound!

I drove it later at Winton and while that was fun having a helmet on took some of the fun away. And a Monty on the short track at Winton as you know is not the ideal setup!

John Hanslow · June 09, 2011, 04:51:12 PM

Here is a comment from Wikipedia re Alfa Romeo GTV for some interest.

QuoteThe top of the range (3.0 and 3.2 litre) versions have three mufflers and four catalytic converters installed at the factory on the CF3 engine and onwards (2001-), which result in a somewhat muted sound. Common aftermarket alterations to the exhaust system are straight pipe replacements for some of the mufflers (usually leaving only a single or double muffler), twin tailpipes (which require modifications to the rear bumper), stainless steel systems and replacing the standard cats with race cats or even cat replacement pipes (on the CF3 these replacement pipes do not give lambda engine light warnings). Additional modifications include the popular air filter replacement by BMC CDA, fitting GTA cams, etc. Modifications such as these completely change the sound produced by the Arese V6 and are said by some to rival the engine note of Italian V8 engines.

TFJ100 · June 11, 2011, 08:24:08 PM

Righto, exhaust replaced.

Standard replacement - lose the back two mufflers and fit a y-section which then leads to quad tips.

Steve at Bay Rd Exhausts did a great job, painting it black, and threading the exhaust through the suspension arms (instead of under the axle) which may prevent it scraping on the ground.

The sound is magic, a bit more raspy at take off, and then transmitting more of the sound at higher revs.

The only drawback is a bit of a boom at 2,500 revs. You can drive around it, but ideally it wouldn't be there.

The car MAY be a bit more powerful, but it could just be that I was playing tunes on the gearbox on my way home and thinking positive thoughts. Let's say I've gained a couple of HP.

Torben