performance tips 03,04 m 45, may be newer too.

[saeedakobiakov]

hello,I got new trick up the sleave for you, if you want.you can get better mpg/performance and sound garantee.Here we go:as you already on our car we have 2 pipes going to one muffler, one of the pipes has valve that opens up at cirtain rpm range/pedal position. the valve is to keep the car quie only.this valve could be adjusted very easilly. you can make this valve open sooner or later by adjusting the nut on the valve.perpuse of the valve is to keep the car quiet at normal driving, but when you floor it , it will open up at very last moment before it hits red line, BUT if you like the car to be a little louder, you can simply make open sooner.

if you got after market muffler you will see big difference in sound and performane, that is how i notice it. ([email protected] the fastest m here talking)

i always had that valve open, but with new muffler being loud(nothing wrong with this) one day with all the gas prices going up i start thinking of trading the car with performance loud muffler, not so good. (dont want to spend money to put stock muffler back).so i un tide the valve and my car got much quiter and i started to get worse mpg.so start messing around with adjustmet and it works. so i did a few diferent positions and all different time i got differet sounds out exhaust.So now if i want to sell it i dont need to put stock muffler back , i just will untide the valve and will get the sould like stock.

so good luck.

based on true story.

caug.p.s.14.1 @100.5 in 1/4.keep the valve open if you want to catch me.

[nmgoodthing]

I removed everything from first resonator back but still have the OEM set up in the garage if I even need to bolt back on the OEM system.

If I drive normal I can get 19mpg out of my M with city driving. I was getting 17 with stock exhaust.

[saeedakobiakov]

you got special set up , one pipe deilio,. this post was related only stock set up or like mine, no resinators to one muffler.later.

[DELUNASC]

Anyway to get a picture of the valve that can be adjusted? Sounds interesting.

Thanks, CD

[saeedakobiakov]

no pics. necs. just jack the right rear , ged under the car from the rear, it will be right there waiting for you. right behind the right rear tire from the inside of course.it spring loaded so you will need to hold it with one hand and use the other to wrap metal wire around it.good stuff.

[DRIPS]

Right rear = Drivers side correct? Can you explain more before I get under there? Wrap wire around it? Please be more detailed so i can go do this!

[DRIPS]

Is this going to kick off any engine codes in my car? Are there any sensors on this thing? I dont need to be causing trouble for nothing but sound.

[saeedakobiakov]

i drove it 7 month or so no problem.as far as right rear = passenger side where i am from . (the opposite side of the muffler)if you ever change the brake or spark plugs , then you will be able to to do this job.i cant write a book about it, but you can trust me when i say "even a caveman can do this".

the fastest/cheapest way to get performance out of this.

i am so good.

[mcrews]

Was visiting and saw this post.I have a F50 02. I removed the rear muffler completely and ran staight pipes and tips.Yes that valve has no sensors attached to it.I have had my valve wired open for over a yr.I have gotten 25+ mpg on the road. 100-300 miles trips.

Didnt realize it was the valve being open......

[IMG][/IMG][IMG][/IMG][IMG][/IMG]http://photos.nicoclub.com/gal...s.jpg

[nmgoodthing]

Mines been completely removed. It will not affect any sensors. It's purely for sound cosmetic.

I highly doubt just keeping this valve open will improve your gas milage.

Caug's improvements have come from his resonator deletions.

[saeedakobiakov]

not true at all.i had all the resinators removed and wired the valve first mpg went up,then 5 month later i add the new muffler. since then mpg went up. again,after that i set the valve back to normal and mpg went down.so there. valve is bad news for mpg.open, open. it is good .

[DRIPS]

So I did some reading about this valve in the Exhaust System manual. This valve opens at 4830 RPM and closes at 4730 RPM. The manual also shows close up pictures of this valve, actuator, and control module. IT says that the valve should not be disassembled..not sure why we even have this aside from sound. I was thinking of removing the entire setup.

What would it cost to take out the exhaust system and replace with aftermarket cat back that is only one pipe? Who makes this?

[saeedakobiakov]

OPENS AT 4800 AND CLOSES AT 4700, DO MEAN 5700?

any place that has pipe banding machine, could make it what ever you tell them to make.i want to know what exactly valve do in the books?i think i know, but what they say?i bet it sound related only. we are driving the luxury car after all.i just cant wait to smoke new M.

[nmgoodthing]

So I did some reading about this valve in the Exhaust System manual. This valve opens at 4830 RPM and closes at 4730 RPM. The manual also shows close up pictures of this valve, actuator, and control module. IT says that the valve should not be disassembled..not sure why we even have this aside from sound. I was thinking of removing the entire setup.

What would it cost to take out the exhaust system and replace with aftermarket cat back that is only one pipe? Who makes this?

Drips,

It has to be custom made. I have a 3 inch pipe back from the very first single resonator to a duel outlet Dynomax muffler. Couple of mandrel bends. I didn't go completely cat back, I did it for sound, not performance, although I did gain some performance and better gas mileage. It would have been a little to aggressive from the cat back for my taste. I didn't want to sound like a Mustang. I can bolt my stock system right back in if I ever decide to go back. But yea, there are no bolt on systems for this car. It has to be custom made. I am very happy with my set up. Depending on the place I would guess it would range between 500 to 900 to get done. Caug has a hook up, that's why he didn't pay too much for his.

[Double E]

I went after this valve this weekend. I found it easly enough.

It appears that the cable-driven actuator had never moved since it left the factory from the amount of routine road dust that was on the cable. For example I would have assumed that the cable moving in and out of its mount would have at least removed some of the accumulated dust so I could see where it needs to be tied in the open position....but maybe not.

I know for certain that it's been well into the RPM level for it to actuate if it is working correctly...

That being said, just looking at it from underneath, is there a way to know where the valve is ideally positioned so it can be tied open? In other words, will it also open up if the engine is revved to @4800 so I can see where it needs to be tied open?

[mcrews]

my recollection of this topic from earlier posts is that it is a 'kick-down' valve.when you accellorate hard, it opens to allow the exhaust to flow better.Also, it seems that those who remove the rear muffler notice the effect of it.so there is some corelation with the stock muffler.

I have removed my rear mufller and noticed the effects of the valve in it's standard mode. I have wired it full open and the results are noticeable.

smoother on hard accl. not just the sound, in fact the valve doesnt seem to effect the sound. the closest thing I can compare it to is "down****ing" it does it smoothly w/ no muffler and valve wide open.

[xerexabante]

Well, the other day I got a coat hanger while the F50 was on the lift and opened the valve wide open. It seem to pull harder that before, noticeable more pwer that before. I will keep mine open. Great mod to do took 2 mins to do. Now I got a deep hummm on idle better than before so so quiet.