shooffnyc

Here is a video of how the exhaust setup looks from underneath.

Here is a short video of startup and rev. Going to take some better revs this weekend and some drive-bys.

Jack_88

Shame the turbo cars can't make that wonderful sound. I wouldn't trade the power for it, though.

AlexMercedes

Sounds amazing, great job! There's just one thing that really bugs me: The exhaust tips. The bumper has a factory cutout for only one exhaust tip on each side, and the tips you have just looks very out of place. Are you at least planning to get bigger cutouts on the bumper to accommodate for the quad exhaust? I would still just go with the factory dual tips, it just looks the best in my opinion.

Also, have you decided on going back to true duals, or are you going to keep the Y-pipes?

shooffnyc

I thought the quad exhaust tips would give an exotic look and thought wouldn't look too bad. I was wrong. They actually stick out more than I wanted. When they were mounting it, I measured it from looking at it underneath. On the top I didn't account for the bumper curving inward.
The stock tips appealed to me until I realized how it was just a piece covering the actual muffler tip. That's why I wanted a different one.
Yeah I'm going to try to make it into true duals soon. I still think true duals are higher pitched.
When I change it back to true duals and remove y pipe I might change the tips.

tusabes

You need to just floor it and hold the high revs , not quick blips- make it scream !!!

ZephTheChef

Does that work on the non-turbos? The TTs limit the throttle position or fueling or something to cap the RPMs in Park/neutral. It definitely sounds different and doesn't rev very high as compared to loading it in gear (good way to break cv shafts, lol) or actually driving. I'm not sure what the control mechanism is exactly, as they don't hit a traditional spark rev-limiter like most cars...it just flatlines and holds around 4000 or so, I think it's probably a throttle blade position limit.

Welwynnick

Yes, the engine is rev-limited to 4k rpm in neutral and park.

ZephTheChef

Do you know the mechanism for it though? It doesn't sound/feel like the typical ignition cut/cylinder drop limiter. I'm guessing it's the electronic throttle body ignoring pedal input and being closed to maintain RPM.

ItalianJoe1

That's how almost all factory rev limiters work on electronic throttle cars now. It's very boring by comparison lol.

My 350Z would just close the throttles a little at 158mph on the stock speed limiter like you took your foot off the gas, and it was such as strange feeling, like the pedal stopped working. On that car you could set different limits to use throttle, fuel and spark. By default the throttle does everything, once I got into tuning it and tried the spark cut limiter I got good proper machine-gun noises from the catless exhaust on the limiter. Much better

ZephTheChef

My first experience with that kind of thing was on my 1994 Infiniti Q45...which I'm sure was the precursor to your 350Zs electronic throttle, lol. I believe the primary throttle blade was still cable driven but they actually had a second throttle plate that was electronic that the computer used for traction control and limits. I agree, very odd feeling when it kicks in.

ItalianJoe1

BMW did that for many years on the E36/E46, it had a cable throttle, and a second throttle right in front to activate traction control.

shooffnyc

Took it on the highway today. So far here are my observations.
1. The car idle is actually very quiet. It's actually quiet under 1500rpm.
2. The sound really comes out between 2-3k rpm
3. Past 4k it becomes more throaty than that high pitched F1 sound.
4. There is some high drone going from 1.5k to 2k rpm on lower gears.

Other than that it's pretty good so far. I'm still going to be looking for ways and researching how to make it sound higher pitched before I consider the custom headers.

AlexMercedes

Are you planning on taking a fly-by video? That would be cool.

Welwynnick

Electric throttles must be quite expensive, but from memory, there's a dozen clever things you can do with one unit. See if I can remember:

1. Rev limiter
2. Speed limiter
3. Cruise control
4. Traction control
5. Boost control
6. PAS load compensation
7. AC load compensation
8. ABC load compensation
9. Drive load compensation
10. Gear shift smoothing
11. Idle speed control
12. Cold start fast idle
13. Anti-bunnyhopping (yes, that's a real thing)
14. Low gear re-mapping
15. Oversize throttle?
16. Throttle position sensing maybe?
17. Integrated kick-down switch maybe?

MB do use those load compensation features. The ECU knows how much torque is being applied on the engine by the AC compressor, for example.
Low-gear re-mapping is a LandRover feature that slows down throttle opening when you're in a crawler gear, to help avoid snatching.

Oversize throttle is my idea. Big throttles give more power at high revs, but they can compromise torque at low revs. Therefore use a throttle map that doesn't allow full throttle until you reach half revs, or something like that.

Some of those things you can do with idle by-pass valve or ignition retard, but not all of them.

Nick

shooffnyc

Yeah. I'll have one soon.

shooffnyc

Took some flyby and drive along videos yesterday. Here is one. Will have some more soon.

Jack_88

That's quite a sound to come from a large sedan. It's a wonderful note. How's it at normal speeds?

shooffnyc

Well with the straight pipes, it's actually quite loud. My only complaint is the drone at normal speed in city traffic. Highway is actually quite decent and drone is less. The best part is being able to drive in the manual shift mode and shifting gears at the right high pitched tone.

I have another video with my friend recording while driving next to me. I haven't heard my car from without being a driver. I also have some more videos with a dash cam recording how it sounds from the inside. Will put them up soon.

AlexMercedes

Holy crap that's amazing. To be completely honest though, my car doesn't sound too far off at those high rpms! I might just take a fly by of my car to compare it with yours! We are basically running the same setup (nothing after the primary cats) and have the same car except for the two turbos. This should be interesting! I'll have the video up soon.

shooffnyc

By all means do it! LoL.

I am now convinced that this v12 the the best sounding engine Mercedes has came up with. I wonder why many exhaust companies doesn't make high pitched mufflers/resonators for the m137 engines. I know that if some one these exhaust companies like Capristo, Armytrix, Kreisseg, make just mufflers like they do for the Ferraris, this car will sound like the F1 without the manifolds.

I am actually going to contact Armytrix and see if I can convince them to design an exhaust system using the same techniques they use on their Ferrari exhaust. Take a look at the picture of the Ferrari 599 GTO exhaust. That muffler design can almost fit into the S600.

tusabes

What was your rpm during the fly by ? I heard your car shift and you slowed down for the curve ahead

To replicate the Japanese videos manually put your car in first and leave it there , then you don't have to go so fast . Remember the f1 beastly sound only comes out fully right before the rev limiter !! When it up shifts you'll lose the sound

shooffnyc

I took it all the way to 6500rpm. I believe it was in 3rd gear. It was the first time I floored it since installing the exhaust. Wanted to see how it sounds with full throttle.

But yeah on lower rpm is where the sweet spot is. I will show that on the other video with my friend recording while next to me.

MBWorld Editor

Great stuff! Thought the front page crowd would think so too...
https://mbworld.org/articles/imitati...00-f1-exhaust/

shooffnyc

Wow thanks!
Here are some more video footage of the car staring up/revving and doing some interior drive shots.

Jack_88

It really hits that sweet spot right before the shift point. I don't if I prefer that or the S8 with Milltek exhaust. Both have a very exotic exhaust tone for such unsuspecting cars. The looks you must get!