Exhaust options: more "growl" but not too loud?

[P_G]

P-G thats what im after gut pre cats, x pipe, remove centre boxes, and leave the rear boxes, are your rear boxes standard?

I don't have the car anymore unfortunately but I replaced the back boxes and I kept the cats intact. If I was to do cats then I would keep OEM back boxes.

[MikeFish]

P-G thats what im after gut pre cats, x pipe, remove centre boxes, and leave the rear boxes, are your rear boxes standard?

I think that's a great idea. Looks standard, has the valves still but more noise and power, for reasonable outlay. I bet it sounds really good too. Before I got the Tubi (and other exhaust mods) I disconnected my valves so they were always open (none of of this sport mode or under whatever rpm in 1st, 2nd and third business), just louder all the time. I must say when I was standing outside of the car with one leg in and gave it a little revving it sounded amazing.

[sakimano]

A custom remap will be needed for the downcats. I did not find them raspy.

Why would anyone need a custom tune for something as simple as downpipes be they catted or decanted?

A good off the shelf tune along with the bosch ecu will adapt very nicely to these modifications. Custom tuning sounds fancy but I have never seen a simple na setup need a custom tune for simple mods like exhaust etc. With that being said there are not many good off the shelf tunes lol. Jhm does very well and can be flashed over the Internet using their server.

[TonyHayers]

JH-who? Never heard of them.

[sonny]

A custom remap will be needed for the downcats. I did not find them raspy.

Why would anyone need a custom tune for something as simple as downpipes be they catted or decanted?
.

Are you serious? Educate me if im wrong, but by decatting or removing the precats will change the engine characteristics drastically and also the EML light will come on.

[sakimano]

A custom remap will be needed for the downcats. I did not find them raspy.

Why would anyone need a custom tune for something as simple as downpipes be they catted or decanted?
.

Are you serious? Educate me if im wrong, but by decatting or removing the precats will change the engine characteristics drastically and also the EML light will come on.

You're not describing anything that should require a custom remap. Keeping a cel at bay? Any old tune can change the catalyst efficiency acceptable ranges to avoid the normal catalyst efficiency code from piggies, cat less stockers or aftermarket downpipes. Not that they all do of course... But I can't see why they wouldn't. Why would anyone want to do this multiple times for the most basic modifications (catback, downpipes)

Further the ecus adapt very nicely and a good tune can have plenty of headroom to allow your modlist to grow while staying safe. Unfortunately some of the tunes can't do this and we end up with everyone saying you need a custom dyno tune. This platform seems to love the sound of a custom tune... Whether it's necessary or not.

[TonyHayers]

Car is in fabricators this morning to get crossover fitted. Hoped to do a before video of my stock exhaust, but you'll have to excuse me because it was a freaking BLIZZARD. Left my camera with them to get some photos of it. Tony Banks reckons it should be good for an extra bit of power (20-25bhp!?) due to the firing order across the cylinder banks helping provide some extra draw/flow. We'll see

[MikeFish]

20-25bhp is a massive increase for a NA engine! You taking it back to the rolling road to see the difference?

And don't forget to take a video of it tonight not just photos! We want to hear that bad boy. And I don't care if there is a blizzard.. it's your duty!

[P_G]

Car is in fabricators this morning to get crossover fitted. Hoped to do a before video of my stock exhaust, but you'll have to excuse me because it was a freaking BLIZZARD. Left my camera with them to get some photos of it. Tony Banks reckons it should be good for an extra bit of power (20-25bhp!?) due to the firing order across the cylinder banks helping provide some extra draw/flow. We'll see

With the greatest of respect to your fabricator there is not a chance you'll see a 20-25hp gain on an x-pipe. 5-7 tops (if that) is what I was quoted from my fabricator due to exhaust gas scavenging and that is based on his experience of manufacturing systems for motorsport teams.

[TonyHayers]

20-25bhp is a massive increase for a NA engine! You taking it back to the rolling road to see the difference?

And don't forget to take a video of it tonight not just photos! We want to hear that bad boy. And I don't care if there is a blizzard.. it's your duty!

Hahaha. Ok, I'll do my best. Good excuse to get out and do some drifting on a huge disused car park near me

[sar]

i echo what PG said, i would be surprised about any gain in hp it certainly wouldn't be measurable on a dyno.
the best full exhaust system out there for the rs4 might get you 20-25hp.

[TonyHayers]

OK, got car back earlier. The guys took a few pictures as they went along (see below). I've had it done with flanges and collars so that the stock silencer can be refitted later if I need to.

I do need to get them to do a little more work on it, needs a couple of inches trimming off as the tips are sticking out the rear diffuser like a wheelbarrow atm!

Not had chance to give it a proper blast yet, but on the way back it felt about what I was after - just a bit more aggressive but not mental.

[MikeFish]

Looks very nice. None of the videos seem to work for me though.

What I will say though, is that some people have complained (on a former forum I used to frequent for a former turbo charged car) about the method they used to bend the pipes as it makes an indetation into the pipe thereby restircting the overall size.
Personally I don't think it will make any difference as it is minimal and this is a NA engine.

[P_G]

If they have a proper mandrel bending machine it should be ok and no indentations but that looks more like four sections TIG welded to a middle pipe section? But if it does the job then ideal. Do you get any throttle lift off / clutch ride exhaust burble / popping?

[MikeFish]

What causes the throttle lift off / burble / popping?
And why do you ask? Is it purely because it is desirable or does it tell you something?