CAI & noise...

[Zchild]

Hey bimmer dreamers and gearheads, riddle me this if you will... I've just about finished all of my exterior upgrades to my bimmer and will turn my resources towards interior under the hood upgrades. I'm wondering basically if adding a cold air induction to my car will increase interior compartment noise of any kind. I heard some speak of whistling sounds when they accelerate. I'm also looking to upgrade my exhaust, add a chip and upgrade my spark plug wires to plasma. Thanks in advance for any suggestions that you may have...

[bwiz]

What year and model car do you have?

I have a 2001 530, i installed the cold air intake and a week later upgraded the software to the Shark Injector. There was a difference in sound but nothing really that noticeable. It was more apparent when really stomping on the gas.

About a month after that I put on a SuperSprint exhuast pipe and added a straight pipe from supersprint. In doing so I removed the rear resonator and now the car is louder in the interior going through the gears at lower RPMS but once i reach 60 or so the noise was like it was pre exhaust. It seams to resonate a bit under the rear seats. I dont think it is annoying since I like hearing the engine.

My wife thinks its a bit annoying when she is in the car, but that is why she drives our X5 and not mine.

[Zchild]

I drive a 2000 323i with sports package; additionally I lowered it with an Eibach Pro-System Kit. I'm really trying to find the right compromise in sound between annoying and power. A friend told me that some exhausts add an annoying resonance to your car at road speeds. Thanks for your response.

[Nick325xiT 5spd]

I drive a 2000 323i with sports package; additionally I lowered it with an Eibach Pro-System Kit. I'm really trying to find the right compromise in sound between annoying and power. A friend told me that some exhausts add an annoying resonance to your car at road speeds. Thanks for your response.

Cut the muffler and one resonator off and put a straightpipe in. I did that to my 323 and it's still a lot quieter than my M3 with AA muffler.

[mlytle]

I'm also looking to upgrade my exhaust, add a chip and upgrade my spark plug wires to plasma. Thanks in advance for any suggestions that you may have...

plamsa coils are a waste of money. it has been documented several times that they add a grand total of zero hp over new stock coils.

and of course you know that the car can't be "chipped". it requires a software update that is done via the odb port with products like the shark injector.

[Zchild]

I didn't know about the plasma coils, I do on the other hand know that my car must have a software upgrade, I was using chipped in the same vinacular as injected. You say well documented... What exactly does well documented really mean? Who documented it and what are their qualifications if you don't mind...
Here is what I have read: The core windings inside these coils have been modified to increase firepower and promote a faster, more efficient burn. This gives your BMW increased torque in the lower range of RPM and more horsepower in the upper range. Exact improvements depend on the current condition of your BMW's engine, but you¹ll definitely feel the difference. They'll also improve your fuel economy, and they're less expensive than BMW stock replacement coils. Thanks in advance.

[Nick325xiT 5spd]

Well documented means that competitive racers like Marshall have seen ZERO benefit from these, even with custom built RACE motors and custom tuning.

[OwnedbyDuncan]

Through the years I have learned to almost never believe the claims about some tuners latest hot part. Back when I had VW Rabbit in the late 70's big bore throttle bodies were the rage as where headers with anti reversionary cones to reduce back pressure. Big single bore throttle bodies caused big problems in drveablity and low end torque. A twin bore enlarged throttle body was better. Anti Reversionary headers with biforcating venturiis despite white papers and dyno calims were worthless.
And their were the silicon spark wires I bought from Accel for the Rabbit.
Better performance, maybe but the wires when at operating temp became soft and pliable. Replaced with Bisch and no problems ever.

Then there were the cold air intake kits big time dyno claims for hp and tirhue gains problem was you lost hp and tirgue when the engine got warm becuase the first intake kits did not have heat shielding. You just warmed the intake air.

Then their are lowering springs whose spring rates are actually softer or the same as stock for E30s. Big name spring manufactures( Eibach and ST) put this crap out and on the track the springs bottomed out and suffered from coil bind.

And lets not forget drilled rotors. They were garbage when they first came out for any car but Porsche. Some still are.

K&N filters do they really make a difference? Worth the money. Seals failed on mine and it fell into the cold air intake box(stock).

You have to deal with reputable tuners and suppliers. Turner Motorsports is good. Jim Conforti is too. Take any clai with a grain of salt. Dyno claims are worthless unless they can be proven on the track.

Dave Apker

[Zchild]

Thanks Dave and all, I'm just trying to get some limited additional HP and Torque without sacrificing performance, ride and engine life. I will concentrate on upgrades to my exhaust, Shark inject my engine and CAI my air filter system. I really appreciate the knowledge base of the users on this forum, keep me striaght folks, cause I love to spend on my number one hobby.

[Nick325xiT 5spd]

You're really not going to get anything other than more noise and a higher rev limiter.

[1996 328ti]

My top speed at the end of the straight is higher so between the flash and CAI, it's doing something. But the main reason for me was the sound and the bump in the rev limiter.

[mlytle]

I didn't know about the plasma coils, I do on the other hand know that my car must have a software upgrade, I was using chipped in the same vinacular as injected. You say well documented... What exactly does well documented really mean? Who documented it and what are their qualifications if you don't mind...
Here is what I have read: The core windings inside these coils have been modified to increase firepower and promote a faster, more efficient burn. This gives your BMW increased torque in the lower range of RPM and more horsepower in the upper range. Exact improvements depend on the current condition of your BMW's engine, but you¹ll definitely feel the difference. They'll also improve your fuel economy, and they're less expensive than BMW stock replacement coils. Thanks in advance.

ahhh grasshopper....you read the manufacturers literature well....

if you haven't found it yet, go to www.bimmerforums.com. a wealth of info on bmw's. try searching for "plasma" in the track, e36, e36 m3 and e46 forums. there have been several threads regarding this product. some folks have done the dyno testing. i haven't personally tried them, but when i got new coils for my maxed out 325is scca race car, i got new stock coils. hint...i don't look for ways to save money on this car....

as for the cai, software and exhaust. enjoy the sound, rev limit increase and removal of the top speed limiter (on the track), but don't expect gobs more hp and torque. all of them together may provide a little bit more, but nothing huge.

why not?
the restriction in the exhaust is the headers and cat. changes behind the cat just don't add much hp. do sound cool though! i recommend the aa exhaust for a compromise between quiet when toddling around town and "noticeable" when you tromp on it. i have had a aa exhaust on my street car for 8 years. love it.

the restriction in the intake isn't the airbox. it's the manifold and the valves. putting an aftermarket intake on does look and sound nicer and provides a smoother air path.

btw, the stock intake IS a cai. it is sealed from engine heat and draws air from the outside. some of the aftermarket "cai's" don't even do that. another marketing misnomer by aftermarket tuners. don't get me started on the use of the term "coilovers"...

enjoy your toy, and i do hope you make it to one of the club driving schools. way more fun per dollar than spending money on parts!

marshall
bmwcca #32847

[Pinecone]

Also, speed at the end of the striaght is more determined by exit speed from the last corner versus HP gains. You could just be driving better.

Not a lot of gains in these motors with simple bolts ons. And trust me, guys like Marshall KNOW, as they will spend gobs of money for 1 -2 HP gains. If for no other reason is that the guys they are racing against will do this.