stupid turbo question

[voltronb5]

how come i cant hear my turbo? the car is chipped with a forge 7 dv... and i dont hear anything, am i just deaf?

some of you people can hear it, or atleast you say you do. but i dont hear anything? sounds like a quite n/a car to me. is my turbo bad?

[DDQ]

Do you have a boost gauge?

It's an Audi, so they wanted to make it quiet. Most people that buy expensive cars don't want it to be noisy. The setup of the car is such that it blocks the BPV/turbo sounds. If you want to hear it more, you could always remove your airbox in exchange for a hot air intake, like the Evoms or LLTek kit. But basically you'll be paying for a $200+ noisemaker that makes your car slower.

[SoleMate]

Originally posted by DDQ
hot air intake

LOL

You could also put in a blow off valve that'd be bad for it if you want the sound.

You could also just burn a CD of a car accelerating that has a really loud turbo & blow off sound, crank it, and roll down the windows so all can hear

[D Piddy]

open yur windows halfway and when u accelerate listen carefully. u should hear a quiet high pitched whine. you prolly won't hear the BPV, i know i can't, but u can hear the turbo boosting

[awe4rings]

I don't know why you don't hear your turbo spooling and then boosting, I do. I like it, sounds refined, cant wait to hear the difference when I install the K04. Maybe you are listening for the wrong sound

[D Piddy]

yeah. it's sorta quiet, but still very distinctive, listen for the whine, i guess u gotta know wut to listen for. oh and btw, how does everyone like my new badass sig?

[nizmosx]

weird i heard mine, try driving it in a parking structure, im sure youll hear it, i have a k04 and LOVE the sounds my car makes. i kinda want to put in my evoms hot air intake for shits and giggles to hear the sounds it makes then put the stocker back in.

[A4Jon1.8t]

I put an EVO intake on mine and have had no problems or loss of power. I set mine lower, shielded it from the engine really good and put the stock inlet tube from the stock air box on it to better direct the air directly into the intake and it works great. I tested it out on a long drive then popped the hood and felt to make sure I wasn't getting a lot of hot air from the engine and the intake area was a lot cooler than the rest of the engine bay. If you do a little extra as far as shielding goes then it will work just fine.
As far as the blow off sound, I can hear it with all the windows up and the radio on, and I'm running a stock diverter valve. Of course it doesn't sound like a BOV would but it's DEFINATLY loud enough to hear. It can be heard really good outside the car too cause I see the heads turn when it blows off.
I know I'm probably gonna get flamed for sticking up for the "hot air intake" but mine, with the way I have it shielded and ducted, works perfect.

[DDQ]

Originally posted by A4Jon1.8t
I put an EVO intake on mine and have had no problems or loss of power. I set mine lower, shielded it from the engine really good and put the stock inlet tube from the stock air box on it to better direct the air directly into the intake and it works great. I tested it out on a long drive then popped the hood and felt to make sure I wasn't getting a lot of hot air from the engine and the intake area was a lot cooler than the rest of the engine bay. If you do a little extra as far as shielding goes then it will work just fine.

Touch of the hand, and butt dyno, really doesn't tell you much. I can assure you that your intake temps will be higher with an open cone under the hood. You can blow all the air you want towards it, but the air will always mix with the warmer bay air.

But, for most of us, the difference in power is not drastic (except for the first gulp of HOT air you get after you come to a stop, and then go again).

I only say this because I also had a cone before, with great heatshielding, and I even ran a snorkel to blow cooler air onto the cone. The power loss was noticeable in the warm months.

Also, you will never need more air than the stock airbox provides, so why bother changing it?

[Devious27t]

exhaust helps alot, my k03 was actually loud before i took it out wot you could hear the sweet sound of a thousand mice squealing to their deaths...

[A4Jon1.8t]

DDQ, I understand what you're saying, and I agree. Talking about hot months, I live in Florida, we have lots of them.
Though I have never had the car dyno'ed, so I don't know the before and after affects. But one thing is for sure, you will definatly move larger quantities of air with an aftermarket setup versus a stock restrictive air box. Never the less, all the air that is ingested into the engine comes from the intercooler, not the air box, as it would on a N/A engine. Have you ever felt your stock, plastic, air box after driving? I will guarantee you that it gets WAY hotter than a metal shielded intake. The heat from that plastic is naturally going to transfer into the air that is passing through the air box at a lesser quantity and slower, due to it's restrictive qualities. The fact that the aftermarket intake is able to move higher quantities of air at a faster rate gives the engine less time to heat that air up. As long as the intake is well shielded, and properly ducted, I am willing to bet that intake temps will be lower on an aftermarket setup. I've been a jet engine mechanic for 8yrs, and also am one year shy of my degree in professional aeronautics, so heat transfer and moving air are a couple things that I am well educated in. Do you think that ANYONE who professionally races A4's has a stock air box sitting under their hood? I bet not.

[DDQ]

I'll try to respond your points below (and by the way, if I'm wrong on anything as far as physics of air etc, please let me know)... Just for the record, I've been down this road before, and if you search around here and AW, and think you'll find all the evidence you need to show you that the stock airbox is superior in the A4 over any other known setup. I don't race, but I have experimented with the intake and logged data in the past. After all that, I'm not back to the stock setup, and for a reason. It's best.

Originally posted by A4Jon1.8t
But one thing is for sure, you will definatly move larger quantities of air with an aftermarket setup versus a stock restrictive air box.

Not really true in our cars, since our engines will never use massive quantities of air. The stock air box holds MORE than enough air for the 1.8 engine, and the air is quickly replaced by the snorkel (especially when you're driving). The stock airbox has NEVER been show to be restrictive in any test I've seen, even with the paper filter. Your 1.8 will never be deprived of the air it wants. (BTW - I think the stock box holds something like 5 liters of air). Also, the stock air box is designed to direct air flow to limit turbulence, and to break the air into streams for more accurate MAF readings (but this is the area where you know way more than me on ) - at least that's what has made sense to me, but let me know if that's off-base).

Never the less, all the air that is ingested into the engine comes from the intercooler, not the air box, as it would on a N/A engine. Have you ever felt your stock, plastic, air box after driving? I will guarantee you that it gets WAY hotter than a metal shielded intake. The heat from that plastic is naturally going to transfer into the air that is passing through the air box at a lesser quantity and slower, due to it's restrictive qualities.

The air in the box is quickly replaced, which means it does not heat up in there. Also, plastic is a very poor conducter of heat, so it is ideal for the airbox. Trust me, you can find plenty of data on this from people who have measured and logged the intake air temps. And many of the studies I saw were from people that do go to the track (unlike me).

Do you think that ANYONE who professionally races A4's has a stock air box sitting under their hood? I bet not.

Well, not many race the 1.8T, since it's not exactly ideal for that. But, the APR Stage III uses the stock airbox. So, wouldn't you think that the box certainly flows enough for a chipped K03? I believe one of the fastest Audis out there, the "Silver Bullet", uses an ITG cone filter, but it ENCLOSES the filters with carbon fiber canisters (see pic below), just like an airbox. Again this supports the argument that you do not want to suck in engine bay air, no matter what, it will always be warmer.


All that said, it's been proven that air flow is not a limiting factor in the 1.8. Rather, heat is the limiting factor, since the turbo and cat are right next to the intake. So, the best you can do is shield your intake from the engine bay air, and seal it off, so it can only pull air from outside.... which the stock air box is perfectly designed for!

For another study on this, see here:

http://www.autospeed.com/cms/article.html?&A=0646

"Hmm, so how much loss is there through the filter? Very nearly nothing at all! And guess what? That is the case on nearly every car - the standard filter poses very little restriction at all in the system.


Look at the Before Filter and After Filter lines - don't get much closer than that, do ya? In the Audi's case, the filter makes up 1 inch of water pressure drop out of the 32 inches total pressure drop that is present. In other words, 97 per cent of the flow restriction of the intake is not the filter. And to hammer home the point, when you make actual on-car measurements, it's pretty well always like this. The airfilter as a halitosis-suffering, smelly, dirty, hairy negative pressure is a total frame-up created by those with vested interests in selling drop-in aftermarket replacement filters."

[voltronb5]

well.. i didnt really want to hear a hot-intake-debate but its all good...

im asking because even though we buy our cars to be quiet... their should be some noise from the turbo?? maybe im asking for too much from my audi...

[DDQ]

Back to your issue...

Yes, you should be able to hear the turbo, but not unless you really listen for it, and you're really hammering it. With a boost gauge, you can easily see that almost all of the time you're driving in a vacuum state, so the turbo really isn't doing "work". But, if you punch it, you should certainly here the high pitched turbo sound at WOT. Nothing crazy, but with windows down and the radio off, you should hear it.

[voltronb5]

hmmm? interesting, maybe i need to stop babying my car

thanks

[joeya103]

I hear it very distinctly, usually more when I push my car hard from low-to-mid speed...once you're past a certain point, the sound goes away again.

That being said, when I first bought the car, I didn't hear ANYthing...and it turned out to be a malfunctioning wastegate. It wasn't closing all the way and allowing the car to boost. I hope that's not the case with you...

My brother has a bone stock A4 1.8T (as far as speed mods go) and you can still hear the turbo, although not as well as mine with a chip and 710N bpv. A better-flowing exhaust will also help...

Get a boost gauge, make sure you're boosting, and that your turbo isn't busted like mine was =P

[joeya103]

If you wanna hear a car that has a nice turbo sound, goto autospeedperformance.com. Download the video for their tru-dual exhaust and listen as his car is at a stand-still, revving the engine. You'll hear a high-pitched wheezing (try to ignore the incredible sounds of the exhaust =P). Most A4s will sound less pronounced than that, but at least you'll know what to listen for.

The best part to listen for is the 0:57-1:03ish part. =)

[JMG]

Originally posted by A4Jon1.8t
But one thing is for sure, you will definatly move larger quantities of air with an aftermarket setup versus a stock restrictive air box. Never the less, all the air that is ingested into the engine comes from the intercooler, not the air box, as it would on a N/A engine.

Air from the intercooler comes from the intake. If the air coming into the intake is heated by the engin bay air it expands and becomes less dense. That means the aftermarket intake takes longer to suck in the same amout of air the OEM one does.

[A4Jon1.8t]

Originally posted by joeya103
I hear it very distinctly, usually more when I push my car hard from low-to-mid speed...once you're past a certain point, the sound goes away again.

That being said, when I first bought the car, I didn't hear ANYthing...and it turned out to be a malfunctioning wastegate. It wasn't closing all the way and allowing the car to boost. I hope that's not the case with you...

My brother has a bone stock A4 1.8T (as far as speed mods go) and you can still hear the turbo, although not as well as mine with a chip and 710N bpv. A better-flowing exhaust will also help...

Get a boost gauge, make sure you're boosting, and that your turbo isn't busted like mine was =P

That exhaust is on an S4.

[voltronb5]

Originally posted by joeya103
I hear it very distinctly, usually more when I push my car hard from low-to-mid speed...once you're past a certain point, the sound goes away again.

That being said, when I first bought the car, I didn't hear ANYthing...and it turned out to be a malfunctioning wastegate. It wasn't closing all the way and allowing the car to boost. I hope that's not the case with you...

My brother has a bone stock A4 1.8T (as far as speed mods go) and you can still hear the turbo, although not as well as mine with a chip and 710N bpv. A better-flowing exhaust will also help...

Get a boost gauge, make sure you're boosting, and that your turbo isn't busted like mine was =P

thanks for the help advice... since i didnt hear my turbo at all... i was thinking it was strange... i guess i'll have to get a boost gauge, maybe turbo timer/gauge combo.... because it just errks me that i can hear the KKK turbo on my friends golf but not on my audi...

[awe4rings]

[QUOTE]Do you think that ANYONE who professionally races A4's has a stock air box sitting under their hood? I bet not. QUOTE]

On many of the race Audi's the passenger side blinker area is removed and a custom ram-air type intake is fabricated to grab cold air from that area, actually outside of the vehicle.

[sumpsfast]

uuuggghhh