Audi A5 Forum & Audi S5 Forum banner

1 - 8 of 8 Posts

·
Registered
Joined
·
11 Posts
Discussion Starter #1
So just got rid of the DPF on my A5, it sounds better but not quite as I had imagined it would. What can I do to make it sound better but not looking to add any more power ? (2007 and it currently has 293hp)
 

·
Registered
Joined
·
1,611 Posts
The sound is very subjective. The best sound comes from a proper DPF delete downpipe. Is this what you have, or gutted DPF?

You can remove the back boxes, these are the only silencer in the 3.0 TDi system. The DPF blocks 95% of the sound as I had a straight pipe exhaust with no silencers, but retained the DPF and it was still quiet! So you may want to add straight through absorption type silencers in place of your back boxes.

I got 310bhp from remap and DPF still fitted. :) I guess yours is the older longer type DPF, I had a 2009 with the shorter type.
 

·
Registered
Joined
·
11 Posts
Discussion Starter #3
The sound is very subjective. The best sound comes from a proper DPF delete downpipe. Is this what you have, or gutted DPF?

You can remove the back boxes, these are the only silencer in the 3.0 TDi system. The DPF blocks 95% of the sound as I had a straight pipe exhaust with no silencers, but retained the DPF and it was still quiet! So you may want to add straight through absorption type silencers in place of your back boxes.

I got 310bhp from remap and DPF still fitted. :) I guess yours is the older longer type DPF, I had a 2009 with the shorter type.
Not sure what gutted or downpipe is, how can I check ?
 

·
Registered
Joined
·
1,611 Posts
Basically, has the DPF been opened, gutted and welded back up, or have you had a DPF delete downpipe fitted. I'm guessing it's the former (there would be about £250 extra charge for the delete pipe) as you 'may' only pass the MOT with the DPF shell so long as the tester doesn't check too much or you know them? :)
 

·
Registered
Joined
·
11 Posts
Discussion Starter #5
Basically, has the DPF been opened, gutted and welded back up, or have you had a DPF delete downpipe fitted. I'm guessing it's the former (there would be about £250 extra charge for the delete pipe) as you 'may' only pass the MOT with the DPF shell so long as the tester doesn't check too much or you know them? :)
Yeah ?, the amount of smoke coming out of the exhaust is not missable, I’ll probably have to remove the blackbox or not sure what I you called it, what are they and what is their role in the car
 

·
Registered
Joined
·
11 Posts
Discussion Starter #6
Yeah ?, black smoke coming out when I rev it in low gears not sure I can pass MOT in normal conditions. One more question, my car is euro 4, is it possible to retro fit to Euro 6 not necessarily in UK ...
 

·
Registered
Joined
·
1,611 Posts
The back box as it is often referred to as, is the rear silencers. They reduce the sound from the exhaust. Yes, I think the smoke emission may be a problem for the MOT as that points to the fact the DPF has been removed.

It would be very difficult to retro fit or upgrade to Euro 6 compliancy as there are more sensors, different ECU mapping, more parts etc etc

Also the car shouldn't really smoke. The 3.0tdi is a good 'clean' engine. The black smoke is normally from a poor generic remap. A good remapper can reduce the smoke.
 

·
Sponsor
Joined
·
2,384 Posts
You won't be able to retrofit euro 6, nobody is doing so for passenger vehicles, though a couple are for HGVs and buses. You'd need to put the DPF back, and add an SCR/adblue.

A well tuned motor shouldn't smoke as mentioned above, sounds like a off the shelf genetic map.
 
1 - 8 of 8 Posts
Top