Just got these:





This is the "race" muffler, it's 10db louder than stock, very deep sound. Tailpipes available in various design, probably going for the lipless ones. Ø100mm
Probably too loud when fitted with the rest of the exhaust.

We're talking about this too:

 

This IS the best thread ever
Where will you place the cutout? Before the second cat?
Which brand is this catback exhaust?
Do you have possibility to post video/sound-clip?

 

I'm not sure if I can talk openly about the brand of the exhaust, as they are not official vendors here.
The car is being used for full exhaust development (turbo downpipe included) at the factory headquarters.

The cutout will be in the rear muffler, when open it'll be a straight pipe!
They are using a 65mm drilled pipe for the silenced route, inside a bigger box transversally mounted, so performance should be the best in both modes.

A centre resonator is probably in order but there will be an option for a centre pipe so valve open->no silencer at all!
Not really sure what to do about it, centre pipe or resonator, what do you think?

I've got a short clip of the race muffler, which is the one in the pictures, but that won't go on this car as it'll get the bigger, quieter, E.E.C. approved muffler + the bypass and valve.

It sounds good though, even if it's not properly run in (usually it takes 1000+km) and it'll be obviously much cheaper than the valve system, so it may be a good choice. It doesn't drone much with the rest of the stock system.

 

That setup looks great, that what ive really been looking for, simple design. However i do bet it will be pretty loud with just that muffler. I can see it sounding a bit better with a larger muffler or resonator midway though the catback.

Honestly, I think any decent exhaust shop should be able to put something like that together for a few one hundred bucks.

 

[QUOTE=Gardus;4007091]
I've got a short clip of the race muffler, which is the one in the pictures, but that won't go on this car as it'll get the bigger, quieter, E.E.C. approved muffler + the bypass and valve.
QUOTE]

WELL... Lets hear it!

 

They've just published the 1st official video.
I'm told this is not the definitive "race" muffler, it may be modified to make it lighter and even louder.

I'm waiting for updates about the system with the bypass valve and the rest of the system.

 

Here's the valved muffler being built!
With the valve closed the gas pass through the transversally mounted silenced. The two 90° bends helps with drone, and the volume of the silenced should give a consistent noise reduction.
Witht the valve open it becomes a straight pipe.
Notice how the two tailpipes work simmetrically in both modes!
Also the diameter of the pipe is 65mm in both modes so no flow bottleneck.
Can't wait to hear it in open mode!




Here's also a video of the QTP valve being used:

 

MOAR PICTURES:









Love the fact that both routes are Ø65mm and that the exit flange on the valve is fitted to a sleeve that can slide.
This way I can use a cap instead of the valve in case it broke down or there is salt on the roads and I don't want to damage it.

 

Can an admin split this thread?
Make a separate one with a title like "F56 valved exhaust"

 

Sweet exhaust!!!

 

 

I've just heard the exhaust with the centre pipe installed.
With the valve closed it's quiet and refined, a bit sportier than stock but no drone inside.
With the valve open it sounds amazing. The bangs on the liftoff are like fireworks thrown out of the window and the car makes and amazing sound from 2500 up to the limiter, it sounds like a rally car.
I can't wait to hear it with also the downpipe with sport cats.
I may decide to fit the centre silencer with the downpipes, but only if it drones at highway speeds with the valve closed.

Also they have tested the car on the dyno in both modes. No difference whatsover, the 65mm quiet route is not restrictive in any way, good news! I can have the best performance all the time.

 

glad to hear the quiet mode is not restrictive. What were the after dyno results?

 

The testing was done mostly to be sure there wasn't any loss, the real gains are given by the downpipe,

All the runs were around the stock value so 205-206 hp and 300-332nm.
The difference in peak torque is because the ECU sometimes uses a slightly higher boost at very low rpm.
Above 3000 rpm all the runs were basically identical.

I hope to see close to 220 hp and 350nm with the full system.

 

Centre pipe and rear valved exhaust on the road.
Just a short preview sadly!

 

More pictures, welded, fitted and working.
I'm told the final product will have a slightly revised layout to make the unsilenced route even straighter and the welding will be a bit better. Hey, it's a prototype after all...





Originale centre silencer compared to the new one and the straight pipe, which is on the car at the moment.
Also, dyno testing!




Stock downpipe removed, working now on the new one with a HJS Motorsport metallic cat.
The original ceramic one is very restrictive, look at thos tiny holes!





A quick peak ath the turbo manifold and outlet.

 

If they solve the issue of EML-codes from gen2 with this downpipe, they will sell a lot!

 

Interested in dyno results. Also would be cool to see you throw a tune on there and test after the downpipe is on

 

Gives me a headache just imagining how loud it'll be. Isn't that illegal to drive around with a busted muffler?
Sorry, but to me, these looks like what a teenager would do on his car. I live close to high traffic road, and I hate it when those old junk Civics with loud exhaust noise passes by. Funny thing is they are actually accelerating very slow.

 

Busted muffler? Its a full exhaust kit with a bypass valve to the muffler. Actually sounds pretty quiet to me when it's closed

 

Rajapruk they had a lot of experience with the N20 on the BMW 125i, 328i, Z4 28i etc.
On those the downpipe with the HJS 100 CPSI cat doesn't throw an error, let's hope the F56 hasn't got a more restricted range of values for the secondary O2 sensor compared to the BMWs!
In that case a 200 CPSI will be necessary, but the performance gains woldn't be as goos as with the 100.

I don't think it'll be too loud even with the centre pipe when the valve is closed, but I have the choice of the centre silencer just in case.
Dyno testing later today, can't wait

 

Did I say I love this thread?

 

A curiosity: they are also thinking about a catless downpipe (obviously) plus a catted front pipe:

 

is it 2 cats in the original system?

 

Just one. In the front section there's just a resonator.

Just got these:






It's being fitted as we speak!