If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
"Len S." > wrote in message ... > I have been enjoying my 02 A4 Avant 1.8T 5 spd for about six weeks now. If > I start off spirited, the car moves our alright, then at around 3k rpms it > snaps me back into the seat, and I have to back off before I shift. I am > guessing this is what is known as turbo lag. It's kind of an awkward > sensation. > Is that typical of these 1.8 T engines? I am wondering if it needs to be > checked out. Thanks in advance. > - Len > > No mate, turbo lag is where you plant your foot & nothing happens for a second or two then whhoooshhhh! It's mot as bigger problem now as on old Saab's etc. What your are experiencing is some kind of overrun for emissions or some other bloody annoying crap reason!! My wife's A4 Cab does the same thing & I hate it for that reason only. |
Ads |
#2
|
|||
|
|||
Sounds exactly like turbo lag to me. Some manufacturers get around it
by adding a small turbo (in addition to the regular big one) that spins up quickly despite the slower exhaust velocity at lower rpm. Audi on their 2.7T uses two of the same size, but that engine has enough displacement to provide decent torque even at low rpm. And with each turbo filling just one bank of 3 cylinders, each one can be small enough to compress air at lower rpm while being big enough to compress air at the redline. Engine design is full of compromises. When you say you 'start of spirited' I'm guessing you use some clutch slip to get and then keep the engine near 3000 rpm - until the clutch fully engages and you floor the throttle. If you don't, that's one way to increase the exhaust velocity enough so the smallish motor doesn't spend much time fighting to breathe well. You'll typically get the best acceleration numbers this way. It's also an excellent way to decrease the life of your clutch if done poorly. |
#3
|
|||
|
|||
On Thu, 8 Jul 2004 19:44:21 -0400, "Len S." >
wrote: >I have been enjoying my 02 A4 Avant 1.8T 5 spd for about six weeks now. If >I start off spirited, the car moves our alright, then at around 3k rpms it >snaps me back into the seat, and I have to back off before I shift. I am >guessing this is what is known as turbo lag. It's kind of an awkward >sensation. >Is that typical of these 1.8 T engines? I am wondering if it needs to be >checked out. Thanks in advance. > - Len > > I have a 2004 1.8q and always drive in Tip mode. When I am in 2nd I can feel a little 'bump' at around 2800 rpm or so and then I go to 3rd. I thought this was the lag. What is happening in 2nd then as I go thru the bump? |
#4
|
|||
|
|||
Is it Turbo Lag?
I have been enjoying my 02 A4 Avant 1.8T 5 spd for about six weeks now. If
I start off spirited, the car moves our alright, then at around 3k rpms it snaps me back into the seat, and I have to back off before I shift. I am guessing this is what is known as turbo lag. It's kind of an awkward sensation. Is that typical of these 1.8 T engines? I am wondering if it needs to be checked out. Thanks in advance. - Len |
#5
|
|||
|
|||
Len S. wrote:
> I have been enjoying my 02 A4 Avant 1.8T 5 spd for about six weeks now. If > I start off spirited, the car moves our alright, then at around 3k rpms it > snaps me back into the seat, and I have to back off before I shift. I am > guessing this is what is known as turbo lag. It's kind of an awkward > sensation. > Is that typical of these 1.8 T engines? I am wondering if it needs to be > checked out. Thanks in advance. > - Len > > Your turbo charger doesn't kick in until around 3K rpm. |
#6
|
|||
|
|||
"Len S." > wrote in message
... > I have been enjoying my 02 A4 Avant 1.8T 5 spd for about six weeks now. If > I start off spirited, the car moves our alright, then at around 3k rpms it > snaps me back into the seat, and I have to back off before I shift. I am > guessing this is what is known as turbo lag. It's kind of an awkward > sensation. > Is that typical of these 1.8 T engines? I am wondering if it needs to be > checked out. Thanks in advance. "Turbo lag" is the bit that happens /before/ 3k rpm* The "problem" you're experiencing is "Turbo smile" ;o) -- Hairy One Kenobi Disclaimer: the opinions expressed in this opinion do not necessarily reflect the opinions of the highly-opinionated person expressing the opinion in the first place. So there! * Should finish at a lot lower than this - my chipped engine's "whoa!" point is at about that. |
#7
|
|||
|
|||
Len S. wrote:
> I'm very judicious with my clutching. I'm not letting it slip like you > suggest. I usually am off the pedal asap. The same takeoff happens in > all the gears when the engine gets around 3000, but it is most prominent in > 1st gear. That's the way turbo lag will seem the worst, but when it spools up near 3k rpm, the 'turbo smile' feels the best because of the dramatic difference. The fact you feel the same effect in each gear confirms it is turbo lag and therefore nothing to worry about unless it changes as the miles go by. The lag of the 1.8T actually isn't nearly as bad as early turbo cars from the 1980s. Those engines had _nothing_ below a certain rpm, but once it kicked in the rush was often violent and had somewhat unpredictable effects on handling, especially if you were exiting a turn where smoothness was key to good lap times. Enjoy. |
#8
|
|||
|
|||
I'm very judicious with my clutching. I'm not letting it slip like you
suggest. I usually am off the pedal asap. The same takeoff happens in all the gears when the engine gets around 3000, but it is most prominent in 1st gear. "Byron" > wrote in message news:ZjiHc.1579$6B.1265@fed1read06... > Sounds exactly like turbo lag to me. Some manufacturers get around it > by adding a small turbo (in addition to the regular big one) that spins > up quickly despite the slower exhaust velocity at lower rpm. Audi on > their 2.7T uses two of the same size, but that engine has enough > displacement to provide decent torque even at low rpm. And with each > turbo filling just one bank of 3 cylinders, each one can be small enough > to compress air at lower rpm while being big enough to compress air at > the redline. Engine design is full of compromises. > > When you say you 'start of spirited' I'm guessing you use some clutch > slip to get and then keep the engine near 3000 rpm - until the clutch > fully engages and you floor the throttle. If you don't, that's one way > to increase the exhaust velocity enough so the smallish motor doesn't > spend much time fighting to breathe well. You'll typically get the best > acceleration numbers this way. It's also an excellent way to decrease > the life of your clutch if done poorly. |
#9
|
|||
|
|||
Well then, I guess having a happy turbo is not such a terrible thing, eh?
Turbo smile ... hmmm. So it's not a problem, it's a feature? "Hairy One Kenobi" ]> wrote in message ... > "Len S." > wrote in message > ... > > I have been enjoying my 02 A4 Avant 1.8T 5 spd for about six weeks now. > If > > I start off spirited, the car moves our alright, then at around 3k rpms it > > snaps me back into the seat, and I have to back off before I shift. I > am > > guessing this is what is known as turbo lag. It's kind of an awkward > > sensation. > > Is that typical of these 1.8 T engines? I am wondering if it needs to > be > > checked out. Thanks in advance. > > "Turbo lag" is the bit that happens /before/ 3k rpm* > > The "problem" you're experiencing is "Turbo smile" ;o) > > -- > > Hairy One Kenobi > > Disclaimer: the opinions expressed in this opinion do not necessarily > reflect the opinions of the highly-opinionated person expressing the opinion > in the first place. So there! > > * Should finish at a lot lower than this - my chipped engine's "whoa!" point > is at about that. > > |
#10
|
|||
|
|||
Bear in mind that -- unlike a torquey, beefy V8 such as the one found
in the '04 S4 -- the smallish, 1.8T engine works best above 1950RPM, at which point the turbo is fully spooled up. Also, if you had a larger engine previously (mine was a 3.0L V6) you may be alarmed that optimal cruising happens at what you might consider high RPM's. I typically downshift at 2.5K, and upshift around 4.5K, and cruise on the highway at well above 3K. I still get 28mpg. When I first got my '02 A4 I was alarmed because I was used to shifting much lower, and cruising much lower. These days it's just another way to enjoy the pleasant exhaust note. --Cesar On Sat, 10 Jul 2004 18:12:01 -0400, "Len S." > wrote: >Thanks for the information. > - Len > >"Byron" > wrote in message >newsioHc.1627$6B.623@fed1read06... >> Len S. wrote: >> > I'm very judicious with my clutching. I'm not letting it slip like you >> > suggest. I usually am off the pedal asap. The same takeoff happens in >> > all the gears when the engine gets around 3000, but it is most prominent >in >> > 1st gear. >> >> That's the way turbo lag will seem the worst, but when it spools up near >> 3k rpm, the 'turbo smile' feels the best because of the dramatic >difference. >> >> The fact you feel the same effect in each gear confirms it is turbo lag >> and therefore nothing to worry about unless it changes as the miles go by. >> >> The lag of the 1.8T actually isn't nearly as bad as early turbo cars >> from the 1980s. Those engines had _nothing_ below a certain rpm, but >> once it kicked in the rush was often violent and had somewhat >> unpredictable effects on handling, especially if you were exiting a turn >> where smoothness was key to good lap times. >> >> Enjoy. > = = Cesar Borgia = |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Installing turbo in 146 1.6 TS | SysCold | Alfa Romeo | 2 | January 5th 05 07:00 PM |
GT JTD Turbo lag? | Grahame | Alfa Romeo | 10 | October 20th 04 07:59 PM |
A3 T turbo mods | big up 2 u | Audi | 1 | June 13th 04 05:53 PM |
problem with Audi a4 1.8t 1997 turbo - do i need a new one? | G | Audi | 0 | May 22nd 04 02:35 PM |
Turbo on 164 if possible | Yoeri Gemeen | Alfa Romeo | 5 | May 6th 04 08:17 PM |