DMS or Revo for RS4

[DaveP]

Yes indeed...good info there mate!

Judging by that graph and the graphs of the other maps...would people agree that it wouldn't look like a good idea to run
anything over low boost 6 (timing 3) ?? - (Obviously I suppose that depends on the as yet unanswered question of what the K04's
can take, but we can see what other tuners think in the original graph)

Great thread...nice work Simon.

[FrankC]

A standard car will let the turbos run at around 1bar increasing slightly at top end of revs.
The REVO code is running boost levels at least 60% above the standard setting accross most of the rev band.
I would imagine the KO4s will take a lot more than the Audi stock setting....but 60%
Maybe a phone call to REVO will reveal what the turbos can and cant take.
Either Audi are very conservative with their boost level settings or......?
Cheers fc

Agree totaly with Sitas3 and DaveP....it is of the upmost importance we establish the safe full working load of the K04 turbos

[wazza]

it is of the upmost importance we establish the safe full working load of the K04 turbos

It is all a question of what you call 'safe' I guess. That will be just opinion and each tuner will have their own opinion and why Audi run a lower level for less failures.
The turbos should have a map for what the most efficient values they work under.

[sitas3]

Paul, valid comments and I guess we'll never know how many turbo failures are attributed to running excess boost (or I should say boost levels higher than the Audi set limits).

consider also that the same K04 turbo on an S3/225bhp TT is specced to run at 0.8 bar of boost by Audi. It is considered that the K04 on the 1.8t engine cannot run at sustained levels above 1.5 bar - is this because of the engine design/lack of airflow or simply the turbos cannot take it?

Also something else to think about. Surely higher levels of boost will cause higher temps as well. Things are already hot enough under that hood.

[sitas3]

Consider also that the boost sensor is only registering 1.55 bar of boost on the Audi cars. Do tuners have mechanical boost pressure gauges plumbed in when they are tuning cars?

[bobjebb]

A standard car will let the turbos run at around 1bar increasing slightly at top end of revs.
The REVO code is running boost levels at least 60% above the standard setting accross most of the rev band.

Frank where did you get this info from?

If you fancy calling REVO -(0)1327 301901 speak to a guy called Doug who is very friendly. I'd be interested to know that everything was hunky dory - I was going to call him but don't understand it well enough

Cheers.


Bob

[alastairg]

Consider also that the boost sensor is only registering 1.55 bar of boost on the Audi cars. Do tuners have mechanical boost pressure gauges plumbed in when they are tuning cars?

When the RS2 was done Mihnea had a mechanical boost gauge along with EGT, intake temperature and wideband lambda monitoring throughout.

[S2tuner]

Thanks to Alastair for the details

I for one try not to exceed 1.5 Bar when mapping a "normal" (stage 1-ish) S3, S4 or RS4. I have a very fast datalogging system (40 values logged at 15 samples per sec) that allows very precise logging, however, for boost, I do prefer a mechanical boost gauge, especially if I know boost is going to exceed 1.55 Bar (maximum boost that the ME7 MAP sensor can measure so far, I'm working on a 2.0 Bar sensor conversion for big turbo kits currently).

IMHO, boost on an RS4 shouldn't exceed 1.45-1.5 Bar, and more than 1.2 Bar at the redline is not reasonable. Even Milltek downpipes don't help, because the issue is the efficiency of the compressor... I have recently mapped a complete RS4 conversion in a french S4, on the stock S4 ECU, and the car is running close to 500 BHP with a front mounted intercooler and a complete decatted exhaust+milltek dual system... Max boost on that S4 is 1.6 Bar (measured with a calibrated mechanical boost gauge) in the midrange, 1.35 Bar at 6000 RPM and 1.2 Bar at 7100 RPM. This is the efficiency limit of these turbos running that front mounted IC kit, but there might be more to be had by running Milltek DPs, as it's only running RS4 DPs with no precats and main cats for now...

The car kicks a 500HP Supra's a$$ from 100 to 280 km/h, and gets beaten by 2 carlengths by a 550HP GT2 at 280km/h...

HTH,

Mihnea

[sitas3]

OK thanks for the info Mihnea. I guess the question we should be asking is this: is it safe to hammer a car around (eg on a track) if the boost exceeds 1.55 bar using standard downpipes/cats and intercoolers?

[S2tuner]

@si: IMHO not, especially with stock DPs/cats, but the ECU has failsafes integrated that will prevent you from grenading the engine, e.g., if the EGTs go too high, the ECU will just dump more fuel in and you'll eventually start losing power. But it will be in no way any good on your turbos...

HTH,

Mihnea

[FrankC]

A standard car will let the turbos run at around 1bar increasing slightly at top end of revs.
The REVO code is running boost levels at least 60% above the standard setting accross most of the rev band.

Frank where did you get this info from?

If you fancy calling REVO -(0)1327 301901 speak to a guy called Doug who is very friendly. I'd be interested to know that everything was hunky dory - I was going to call him but don't understand it well enough

Cheers.


Bob

Bob....spoke with Doug this afternoon regarding boost levels....his take is they(REVO) are happy to run the turbos at 1.5ish bar with further increase during over boost.
We also spoke about the screeching noise that lads had mentioned during the trial and he put this down to being turbulence(shape of the intake) rather than a mechanical noise.
He assured me that while the trial file will remain in the ecu,it can be over written by other tuners code.
Chatted about Audis boost levels for the car,and agreed that the level was reduced for maximum reliabilty.
Cheers
Frank

[S2tuner]

Honestly, I have to disagree. I have tried on purpose to push my friend's S4 with RS4 engine to see where the screeching sound was starting to happen and it didn't happen until 1.9 Bar boost. IMHO it is not a resonance/turbulence but simply the turbos being pushed too far, actually outside the compressor map if you want to know exactly. Simon's logs prove that Revo push the turbos higher than 1.5 Bar pretty often, except on really low boost levels, where he said performance wasn't really that improved over stock...

HTH,

Mihnea

[sitas3]

Honestly, I have to disagree. I have tried on purpose to push my friend's S4 with RS4 engine to see where the screeching sound was starting to happen and it didn't happen until 1.9 Bar boost. IMHO it is not a resonance/turbulence but simply the turbos being pushed too far, actually outside the compressor map if you want to know exactly. Simon's logs prove that Revo push the turbos higher than 1.5 Bar pretty often, except on really low boost levels, where he said performance wasn't really that improved over stock...

HTH,

Mihnea

so what is the screeching noise then? is it the bearings as Simple suggests or something else turbo related?

More importantly is it safe? I used to get this on my old S3 at times

Maybe we should have an 'Ask the Tuner' section like the Seat/VW car forums..

[bjacks]

So, who's got a mechanical boost guage connected their car running Revo or anyone elses software? I'd like to see how far the levels actually go.
I've never had my car screeching (but it did pink like fcuk today in 2nd) so I guess the boost levels that AmD/Sportec set are not as high as others.

@Mihnea - can you run more boost with an FMIC due to lower IAT's and more reliability?

Cheers all

Ben

[Tomson]

Right, I have just changed to timing 6, low boost 9. Canny boot it at the moment as Cheltenham is full of drunken Irish - but going to the 'smoke' at the weekend so will be interesting to see the differnece.

Minhea - please can you come back to me with a final price, as PM'd earlier. Then we can sort out a date - you bring the wine and i'll bring the durex - sorry all it has been a very long day and my brain is now mush.