Newb question about tunes that raise redline

[S4inBC]

Apologies in advance if this has already been covered. I've been lurking here since getting my S4 back in June and have read lots of good information.

Something puzzles me a bit though. I have read that pre-facelift cars are faster, partly due to their higher redline and shift points. The manufacturer decided to lower the redline for MY 2013+ cars. Presumably, this would have been done for safety/reliability reasons. Full throttle operation is not part of anyone's economy testing cycle so I don't think is was done to post a better fuel consumption number on the window sticker.

As far as I can decipher, part of the extra power that most tunes achieve for the newer cars comes from raising the redline.

2 questions then. What was Audi's reason for reducing the redline? The second, which has been largely answered in other threads questions the long term reliability of tuned facelift cars. By undoing what the manufacturer has done, are owners of these cars jeopardizing their long term health/reliability?

[S4NJ]

I know the TCU tune raises redline, but I'm not sure about APR Stage 1. I have to go read their website and check it out.


Sent from my iPad using Tap,Tap,Tapatalk

[Sean@APR]

I know the TCU tune raises redline, but I'm not sure about APR Stage 1. I have to go read their website and check it out.


Sent from my iPad using Tap,Tap,Tapatalk

We can raise the ECU rev limit to whatever we want on a DSG car and it won't matter. The TCU ultimately decides when it's going to shift and that's that.

We do raise it in the Stage 1 and Stage 2 ECU tunes, but you won't see that higher limit on a B8.5 DSG car without a TCU flash.

[S4inBC]

Thanks for the reply guys. So was the lower limit imposed as a means of safeguarding the health of the transmission rather than the engine?

[Sean@APR]

Thanks for the reply guys. So was the lower limit imposed as a means of safeguarding the health of the transmission rather than the engine?

Transmission is happy much faster than that. It was done for engine side reasons that don't mean anything to somebody that is tuning their car.

[S4inBC]

Do you have any insight as to what those reasons were Sean?

[Sceanzo]

Probably reduces oil consumption as they had such a problem with it in the B8s. Just a stab in the dark.

[B8Addict]

Im assuming because on stock tune the car begins to bleed boost north of 5600RPM so I guess it didnt make sense for it to rev all the way to 7200. Just a thought.

[pdqgp]

It was done for engine side reasons that don't mean anything to somebody that is tuning their car.

what's that mean?

[pdqgp]

Probably reduces oil consumption as they had such a problem with it in the B8s. Just a stab in the dark.

My B8.5 is at just under 15k with zero burning oil. In fact I just checked it again before Christmas and still topped off good.

[GRUMPY-S4]

Are B8's faster? When comparing stock maybe... But with the same tune a B8.5 would be a tad quicker because of the better gearbox.

[14S4GWM]

Are B8's faster? When comparing stock maybe... But with the same tune a B8.5 would be a tad quicker because of the better gearbox.

Grumpy did you take your tapatalk sig off or are you on one of your laptops?

[GRUMPY-S4]

Tapatalk for life!!!! Lol

Took it off and was waiting for you to ask!!!! Lol

Im in IT and refuse to use my laptop outside of work! So I always just use my phone

[jokingjimmy]

Apologies in advance if this has already been covered. I've been lurking here since getting my S4 back in June and have read lots of good information.

Something puzzles me a bit though. I have read that pre-facelift cars are faster, partly due to their higher redline and shift points. The manufacturer decided to lower the redline for MY 2013+ cars. Presumably, this would have been done for safety/reliability reasons. Full throttle operation is not part of anyone's economy testing cycle so I don't think is was done to post a better fuel consumption number on the window sticker.

As far as I can decipher, part of the extra power that most tunes achieve for the newer cars comes from raising the redline.

2 questions then. What was Audi's reason for reducing the redline? The second, which has been largely answered in other threads questions the long term reliability of tuned facelift cars. By undoing what the manufacturer has done, are owners of these cars jeopardizing their long term health/reliability?

I don't usually post assumptions, but I'll bet it's the same damned person at Audi that decided to install that stupid clutch cylinder thing. And leave the transmission mount free floating. Someone worried about people buying this car that don't know how to drive lol.

[tgsweat]

I could be wrong, but i thought the b8.5 and b8 has the same 0-60 and quarter mile times stock despite the lower redline of the b8.5. This is possible because the b8.5 has longer gearing than the b8. Like i said, i could be wrong. Check out the quarter mile thread. I don't think the b8.5 stock is "slower".

[S4inBC]

OK, perhaps saying the B8.5 is "slower" is the wrong way to put things. I think what really raised the issue for me was a post by someone from one of the tuner shops saying the B8 offered greater performance potential because of it's higher rev limit. As a newb to the platform I'm not aware of any history that would have required them to lower the redline, and I'm trying to fill that gap in my knowledge.

[GRUMPY-S4]

Possibly longer gears drove lowering the rev limiter?

[stereojorge]

We can raise the ECU rev limit to whatever we want on a DSG car and it won't matter. The TCU ultimately decides when it's going to shift and that's that.

We do raise it in the Stage 1 and Stage 2 ECU tunes, but you won't see that higher limit on a B8.5 DSG car without a TCU flash.

What do you officially raise it to on a Stage I/II tune for a 6MT car? I've been curious of this. Thanks!

[schirm]

What do you officially raise it to on a Stage I/II tune for a 6MT car? I've been curious of this. Thanks!

Updated APR file red line is 7,400 on 6mt

[Mat@1975]

Hello,

I think it is not a reliability issue that lead to lower the redline on 8.5 dsg's because the redline is still 7200 rpm on manual versions.

Another hypothesis is that AUDI realized that the S4 was a bit too "dynamic" compared to the RS4 (in europe). And that the 2 cars were too close in terms of engine perormances...
(S4 333ps but actually ~ 350 vs. RS4 450 ps but actually ~420-430 ps)

BR

Mat

[Mat@1975]

Transmission is happy much faster than that. It was done for engine side reasons that don't mean anything to somebody that is tuning their car.

what's that mean?

+ 100000

I am verry curious of explanations for this.

BR

Mat