I will try to record onto a regular cassette and I can even mail it to you...

MJ

While I do understand some things about cars, there are a few mysteries I do not expect to understand. One of them is how an engine stays together while its pistons and rods are moving back and forth more than 100 times per second. I don't get that.

I also do not understand how exhaust pipes can keep engines so quiet. Not just Porsche engines. That Cadillac that goes by wihtout making any engine sound, very possibly has a 455 in it that is EXTREMELY loud without the exhaust system.

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'83 SC

thanks! i'll e-mail you with my address. try to get these sounds on there:

1) motor with just headers (and rev it a few times)
2) motor with no heat exchangers (only a second or so)
3) motor with headers and heat exchangers
4) motor with everything including muffler

it would be a great way for people to hear what a good running motor sounds like. that way they can compare it to theirs if they think they are having a problem with their car.

thanks!

obin

also, 9eleven... i e-mailed you some info, but your e-mail address that you registered to Pelican Parts is not a valid AOL address. this is some info you might find useful, but like i said, e-mailing you got this response from AOL:

----- Transcript of session follows -----
... while talking to air-zd01.mail.aol.com.:
>>> RCPT To:<asd911901s@aol.com>
<<< 550 MAILBOX NOT FOUND
550 <asd911901s@aol.com>... User unknown

Reporting-MTA: dns; rly-zd01.mx.aol.com
Arrival-Date: Mon, 16 Apr 2001 17:12:30 -0400 (EDT)

answer to the first question: lubrication, and removing heat are the keys. metal is strong stuff and it can move at rates even faster. what prevents an engine from turning into a big paperweight is the oil not only removing friction, but transferring kinetic energy away from the metal.

the answer to the second question is best said by quoting automotive101.com:

"The Muffler
Exhaust gases leave the engine under extremely high pressure. If these gases escaped directly from the engine the noise would be tremendous. For this reason, the exhaust manifold sends the gases to a muffler where they go through metal plates, or tubes, with a series of holes. The pressure of the gases is reduced when they pass through the muffler, so they go out of the tail pipe quietly.

The muffler is made of metal and is located underneath the body ofthe car. It's connected between the tail pipe and the catalytic converter.

There are two types of muffler design. One type uses several baffled chambers to reduce noise. The other type sends the gases straight through perforated pipe wrapped in metal or fiberglass. This type of muffler is designed for the purpose of reducing back pressure and, consequently, makes slightly more noise.

Since a muffler cannot reduce the noise of the engine by itself, some exhaust systems also have a resonator. Resonators are like little mufflers, and are usually the "straight through" type. They are added at the end of the exhaust system to take care of any noise that has made it through the muffler.

The muffler quiets the noise of the exhaust by "muffling" the sound waves created by the opening and closing of the exhaust valves. When an exhaust valve opens, it discharges the burned gases at high pressures into the exhaust pipe, which is at low pressure. This type of action creates sound waves that travel through the flowing gas, moving much faster than the gas itself (up to 1400 m.p.h.), that the muffler must silence. It generally does this by converting the sound wave energy into heat by passing the exhaust gas and its accompanying wave pattern, through perforated chambers of varied sizes. Passing into the perforations and reflectors within the chamber forces the sound waves to dissipate their energy."

obin

Aw c'mon....I thought everyone did the fire up the car without a muffler trick?

It's a right of passage....

BTW...the Pacer and Gremlin both being American Motors cars are BOTH the worst POS known to mankind.

Cold air? Gimme a break. Cheap cars=cheap valves.

As to Porsche's....I run straight pipes off the headers....no problem.

Live a little...unless the track has a noise limit.

This reminds me of the salute to Dennis Jenkinson, the famous British auto enthusiast and writer, I believe he was the navigator for Stirling Moss in the Mille Miglia in a Jag back in the fifties, and they won.
He died a few years ago and at the next big race, as a memorial,all the drivers redlined their engines for one wild minute.
Surely better than a minutes silence.
Ned Monaghan

Great reminisence of Jenks, Ned. I'm sure some of our UK friends remember him fondly.
He loved Porsches, by the way. Drove a worn-out 356 everywhere in Europe to report on the races. A great fellow!


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Doug
'81 SC Coupe (aka: "Blue Bomber")
Canada West Region PCA
members.home.net/zielke/911SC.htm

We all have to do that sometime in our lives..
I started a Chevy 350 on an engine stand one time, no exhausta at all..

It was very loud, a fried about a mile away said he heard it very loud...

It must me in the male gene's..

Bruce

heh heh mikez. yeah, they are terrible little cars. i think they all rusted to pieces. also, i honestly don't think that "9eleven" owned one, because he doesn't exist as a user. he's just a troll that visits the 911 boards and pretends that he owns a 911. look up his info and you'll see what i mean http://www.pelicanparts.com/ultimate/wink.gif

obin

If you want to hear some incredible engine sounds, check out Mark Hargett's site www.mark.hargett.com. Here is his post from back at the beginning of the month. When I first played it, it woke my kids up in the next room! Unreal!
Adam.


"Well, I haven't sent the video to get converted to an mpeg yet but I have updated my website with some wav files and pictures of the engine stand I am using. Check it out and let me know how they sound. I just used my laptop to record so I don't think the sound quality will be very good."
------------------
Mark
www.mark.hargett.com
mark@hargett.com

Hello

Oh what a beautifull noise. We used to tune the carbs by the blue flames from the exhaust back in those days when i was inocent. ( Hm, say was in shool then )

Not sure about the valve story just keep the throttle open and so there will be no way for rushing back fresh air.

Obin you must hear a 2,0 906 engine at 10 000/min with just straight runners.

No four will sound equal maybe the Dino engine can make similar sounds.

Roaring Silence becourse the engine is sucking back the own sound emmision.

Low frequency is pure stomac massage.

Grüsse

Grüsse

I went to a vocational high school, and we had an aviation shop, which is what I majored in. In our shop, we had an engine test cell with a seven cylinder radial aircraft engine, all hooked up and fully functional. Every year we had an open house, which was pretty much the only time we were allowed to fire up the radial.

Well one year I was the one at the throttle, and though the teacher didn't want us revving past half throttle, I was a senior and just had to. I cracked the throttle slowly up to wide open, and I cant describe the sound. It was like the world was ending and there was a trainwreck outside, while a tornado was hitting the building. It was felt more than heard. Teacher was in a different part of the building but heard it anyway. That was almost twenty years ago, they probably got rid of it in these litigious times. We also had an Allison V-12, but I never got to hear that one.

per obin's request I have recorded my engine,and with his expertice, I guess he will post it...

I am still working on putting the HE's on...and it is 1AM in the morn...and I have to finish this by tomorrow, cuz my parents (yes I am only 22) will be back in town, and I lose my mother's benz...I am off to Home Depot (gotta love 24hrs) to buy some washers...

MJ

Good to hear I don't exist!
Although my e-mail addy is in error, I don't think I am going to correct it, I am neither interested in nor have time for unsolicted e-mail correspondence from unknown nutcases.

You sound like a person with a lot of character
...as in CARTOON CHARACTER
http://www.trollalert.com/Character/character2.gif

everyone on this board verifies their info so that people can prove who they are. ones that drop into the board with unverified info to stir things up are "trolls". the 911 board attracts the most amount of trolls per any of the boards. people with Camaros, Mustangs, and Japanese cars saying "blah blah blah Porsche" and they end up disappearing after they start a flame war. this has happened several times before on this board and on others.

interesting eh? smells like a troll, looks like a troll, must be a troll.

---

The best advice for handling trolls: Ignore them, use a filter. Deny them what they seek: provoking others. If they can't find the attention they seek, they'll usually leave to seek better fishing elsewhere.
----
obin

[This message has been edited by Obin Robinson (edited 04-17-2001).]

Obin, please get a grip.
Lightly poking fun at the *924* on a *911* board hardly seems the epitome of trolling behavior.
Why don't you follow your own advice, and ignore it? But for you, my "trolling" would have been 100% unsuccessful. But your nutty over-reaction would make my "troll" wildly successful.
I have read through some of your posts. I was able to quickly discern your status on this board. 'Nuff said.

did someone just say something? naah, must have been a hot wind.

offhand, a few people e-mailed me saying that the links to the car engine sounds are not working. the server in which the Porsche sounds are on is being rebuilt. it will be back online this weekend.

thanks for the patience.

obin

What is this, the pot calling the kettle black?
Obin is king of the trolls. He just won't leave.

this crap is silly...what is this cyber mud slinging...I thought my post was even more popular...but the last 10 have been childish teasing...

Obin I did record the headerless engine...it is awesome...reved it too...I will record the engine with its current muffler set up of a 2 in 1 out bursch...I wish I recorded a normal SC before the upgrade to compare...I almost forgot what my old engine used to sound like...but honestly after hearing the pure engine, the mufflered engine was a big let down...but I will send you the casette soon....

http://www.pelicanparts.com/ultimate/wink.gif Rarly.
In Obin's defence, he does like Porsches a lot and has some interesting info to offer at times. Plus he likes sharing it, which is good!
But C'mon Obin, outwardly accusing others of trolling??????? Lets be nice.

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'72 911 TE