View Full Version : Exhaust question - tuning for sound


metroplex
05-13-2009, 06:41 AM
I was driving to work today when a Japanese sportbike was WOT accelerating in the on-ramp. I let him pass and I thought that it sounded really good. It was more like a high-revving Formula 1 race engine than a Harley.

Is there any way to get that type of sound out of the LNF via the exhaust? Every Magnaflow or aftermarket exhaust setup for the LSJ/LNF makes it sound like a farting sound more than a higher pitched race engine. I understand that has a lot to do with how the engine is setup (piston angle, rod length, RPM range, valves, etc...) and most race engines use velocity stack intake ports rather than an intake manifold.

blackbolt89
05-13-2009, 07:56 AM
um, all i know is that race engines are all HIGH revving. like that sportbike. redline was probably near 12 grand or more. my uncle's car sounds a lot like what youre describing. but its a M5 with a v10 and a 8250 redline.

so i dont think its gonna sound quite the same even if you try as hard as possible. its probably not worth it.

metroplex
05-13-2009, 08:10 AM
I looked at some of the specs for the motors used in the sport bikes, like a new Busa or GSX-1000R and they're 4 stroke 4 cylinder DOHC engines with a much shorter stroke (probably to accommodate the higher RPMs). There has to be other differences that can help propagate the high pitched "race engine" sound. I know the Lotus Elise has a Toyota 1.8L DOHC I4, and it has that race car sound that I like. They rev up to 8000 RPM but the sound is very apparent at lower RPMs as well.

BartSS
05-13-2009, 08:25 AM
Yeah dude but that busa and gsxr1000 rev up to like 15k. My R6 redlines at 14k

Yeah but that busa redlines at like 17k. My r6 redlines at 15k and it sounds like you described

metroplex
05-13-2009, 08:28 AM
What about the Elise? The 1.8 revs to 8k RPM, but it still sounds wicked at lower RPMs. Even the sportbike engines sound great at lower RPMs. The challenge would be to get that kind of sound on the outside of the car, but to keep it quiet on the inside. I hate exhaust drone - I used to run Pypes Violators on my 07 Mustang GT but the drone at 18000 RPM was driving me nuts.

Terminator2
05-13-2009, 08:50 AM
I was driving to work today when a Japanese sportbike was WOT accelerating in the on-ramp. I let him pass and I thought that it sounded really good. It was more like a high-revving Formula 1 race engine than a Harley.

Is there any way to get that type of sound out of the LNF via the exhaust? Every Magnaflow or aftermarket exhaust setup for the LSJ/LNF makes it sound like a farting sound more than a higher pitched race engine. I understand that has a lot to do with how the engine is setup (piston angle, rod length, RPM range, valves, etc...) and most race engines use velocity stack intake ports rather than an intake manifold.

Like this? http://www.youtube.com/watch?v=mBn-2LU4bLU

blackbolt89
05-13-2009, 10:12 AM
What about the Elise? The 1.8 revs to 8k RPM, but it still sounds wicked at lower RPMs. Even the sportbike engines sound great at lower RPMs. The challenge would be to get that kind of sound on the outside of the car, but to keep it quiet on the inside. I hate exhaust drone - I used to run Pypes Violators on my 07 Mustang GT but the drone at 18000 RPM was driving me nuts.

wtf kinda motor were you running in that mustang?! :wtf:








:lol:

umrdyldo
05-13-2009, 10:28 AM
wtf kinda motor were you running in that mustang?! :wtf:

:lol:

I wish my cobalt had droning at 18k RPM :)

8k RPMs was loud enough on my Cobalt LS. Can't imagine what it would have sounded like at 18k.

metroplex
05-13-2009, 10:42 AM
LOL, that was a typo. It should have read "1800 RPM."

So are there any exhaust kits that would give the SS/TC an Elise-like sound?

The Elise's 1.8L DOHC I4 seems similar to the 2.0L DOHC I4 in the SS/TC:

http://www.sandsmuseum.com/cars/elise/thecar/engine/toyota.html

The stroke is comparable as well, yet the 1.8L can rev over 7500 RPM.

About the only MAJOR difference I can tell is the exhaust length is different, and the Elise probably has a real exhaust header (instead of a manifold).

blackbolt89
05-13-2009, 10:49 AM
imagine a v8 at 18k rpm.

metroplex
05-13-2009, 10:57 AM
Here's a pic of the Lotus exhaust:
http://www.lotustalk.com/forums/attachments/f160/88767d1219314841-exige-s-240-elise-supercharged-header-equipped-bigger-piping-than-nas-comparison-std-v-2bular-std-big-bore.jpg

http://www.saclam.com/products/lphoto/lotus_elise_111r_exige2_l.jpg

I can't find any pics of the stock exhaust manifold on the Cobalt SS/TC, but I'd imagine it is a manifold (cast stainless steel) and not an exhaust header.

DGAF260
05-13-2009, 02:47 PM
imagine a v8 at 18k rpm.

f1 engines are LIMITED to 18k

bsbllscnd970
05-13-2009, 02:55 PM
f1 engines are LIMITED to 18k

yea but arent they like 2.4 or 2.6L v8s, lol

metroplex
05-13-2009, 03:02 PM
Like this:

http://www.youtube.com/watch?v=sNFQgPTeHiw&feature=channel_page

seek to 5:00, there's a Lotus Elise that you can hear clearly from the inside of the Mustang GT, above the V8 growl!!

hallss
05-13-2009, 03:31 PM
get on youtube and type in s2000 f1 exhaust it sounds like that

SuperchargedSS
05-13-2009, 03:33 PM
Other than the subie boxer, all 4cyl sound rice imo....

metroplex
05-14-2009, 05:09 AM
It looks like the LNF exhaust manifold is an exhaust log, not even close to the manifolds on the LSJ/L61 engines mainly because of the turbo.

Nal
05-14-2009, 06:25 AM
Yeah dude but that busa and gsxr1000 rev up to like 15k. My R6 redlines at 14k

Yeah but that busa redlines at like 17k. My r6 redlines at 15k and it sounds like you described

so your r6 red lines at 14 or at 15k?, lol, and the busas redline at around 13k I believe

metroplex
05-14-2009, 06:53 AM
The Subaru Boxer engine is old tech. It only has MPFI, and is stuck in the dark ages with its timing belts. I am not sure why it won a Ward's Award. The new WRX STI is slower than the Cobalt SS/TC at Virginia International Raceway. The STI has its advantages, namely the drivetrain.

Sweetsandman
05-14-2009, 09:21 AM
You're not going to get an F1 sound out of a cobalt I'm sorry. Honda engines sound like Honda engines...Subaru Boxer engines sound like Subaru boxer engines. GM v6s sound like...dog shit. VR6s sound like VR6s...the only way you're going to get a completely different sounding car...is a completely different engine.

GTGirl
05-14-2009, 09:39 AM
LOVE how a great car sounds with really good exhaust!

metroplex
05-14-2009, 10:46 AM
I would like to know how to make the Ecotec sound better, not necessarily on-par with a Busa or Formula 1 engine, but definitely not ricy, farty, or gruffy.

The Lotus Elise's 1.8L DOHC I4 looks like a regular Toyota straight 4, yet it sounds amazing. It has a similar stroke to the Ecotec 2.0L LNF, so it's not like one engine is revving really fast all the time. Based on GM's handbook, the stock LNF is good to about 300 hp and 7000 RPM - above that, aftermarket valve springs are needed, as well as aftermarket pistons.

So how can we make the LNF sound like the 1.8L from the Elise?

blackbolt89
05-14-2009, 10:55 AM
f1 engines are LIMITED to 18k

O.O

thats nuts