Steve-O

I've noticed some readers have swapped their ls-3 oem airbridge with sound suppression box attached for the zo6 airbridge which I understand doesnt have the noise suppression box attached.

1. I wonder if there is any performance improvement ?
2. Is the zo6 airbridge noticeably noisier without the suppression
box ?
3. Is there any reason not to just cleanly cut off the nipple that connects
the sound box and plug it or put a cap on it ?

Mike's LS3

1. The LS3 oem air box with silencer or Helmholtz resonance does more than suppress air intake noise. It helps smooth out pulsation between the MAF and throttle body. This allows the MAF sensor to accurately report to the ECM. GM engineers felt it was necessary on the LS3.

2. You will hear a little more intake noise using the Z06 air intake.

3. I wouldn't hack up the oem air intake.

glenB

Nobody has ever done that

Those that haven't report no increase/decrease in performance, just more engine noise when they don't put their foot in it

Steve-O

Sorry, glen but i dont get it.

laconiajack

Don't do something you might well regret. Todays cars are so sophisticated, even changing an air filter to a non-standard one can potentially cause problems (hint, hint).

Steve-O

laconiajack, i agree with reference to big stuff, fuel systems, torgue converter, heads cam swaps but when its an oem filter i feel pretty safe.

i swapped out the oem donaldson paper filter for an Attack Blue and saw a noticeable "seat of the pants" difference.

Don-Vette

Gecko2345

Steve-O

I replaced my LS-3 Airbridge with an OEM Z-06 Airbridge, I bought from a Forum member. I do not track my car, so I would not be the best source for performance questions. I haven't noticed any change in performance, sound, or mileage. I did it mainly for the cleaner look of not having that square box attached. I didn't come up with the idea. It has been posted about many times on this Forum.

studiovette

That's the biggest reason to do it. You can buy a LS7 filter box for like 75-100 . I hated the look of the silencer box so I did it. I also have the attack blue filter. When u get on it, u def hear a bit more sound.



Much cleaner look.

MisterMidlifeCrisis

I did mines. Might be a bit more induction noise but after a drive or two, I stopped noticing it. No performance increase that I can tell. When I was in the swapping process, there was someone who just cut off the resonator and capped it with a rubber plug of some sort.

It looks way cleaner.

Steve-O

I think we all agree its just a matter of appearance . Less clutter and you adjust to the sound even if it is a little louder. Since pulling the fuse on my npp exhaust I spend very little time listening to the radio, im happy hearing the exhaust bubble and growl on downshift so the additional sound wont bother me.

PS I really like the rev matching feature on downshift with my paddle shift 6 sp automatic.

glenB

Placebo effect.

The LS3/7 filter has no restriction to a stock LS3 engine, therefore any potentional gain from a higher flowing air filter will not be recognized.

Meaning, if your engine requires 500 CFM, adding a freer flowing air filter element will not increase this number on it's own, all other things being equal.

Steve-O

----------------
If what you are saying is true, why does the dyno reflect a hp increase and why does the car achieve a higher mph and better et at the track ?

I have to disagree with you . When the computer sees more air, it maps more fuel to accomodate the increase. If there is no computer your logic might hold up but not in the wotld of heavily data driven engines.

For example: Its not like octane. If your engine needs 93 octane not to detonate. Adding higher octane fuel doesnt change anything. I think your logic applies to this example but not to increased airflow.

If an engine is an air pump, which it is, the more air it can take in the more fuel can be mapped in and the pump is more efficient thereby making more power.

sledmaster

When i installed an aftermarket intake on my coupe, i noticed light throttle let off and return was not as smooth without the Helmholtz.

Steve-O

Thats the type of experience I was looking for, its probably a subtle difference but detectable. I think thats what the engineers were going after was exactly what you said. The box smooths out the patterns.

Steve-O

I apologize for the size of the image.

I think we are lucky that they have improved upon the original Helmholtz Resonantor. Constructed from brass in 1890.

You think the box looks bad.

glenB

And you're right, the PCM will increase fuel up to roughly 25%, but, if the LS3 air filter isn't a restriction at ithe LS3s stock HP level, and everything I read says its not, a less restrictive air filter will not make a difference or add HP that isn't there.

I don't have any figures in front of me but I can run them tonight but I would guess that a stock LS3 only uses, at the most 700 CFM and that's probably being generous.

And remember, there are members here pushing over 500 at the wheels that still use the LS7 filter.

Now if you want cold air then that is different that a CAI. There is a thread around here by a forum member that races out in Ca, that ran a few CAI and you could throw a towel over the results.

Steve-O

i know air quality and cfm are different animals but i really believe that even though the stock oem filter in a vette is pretty sophisticated and probably better than 90% of other oem filters, i still think it can be improved upon for not much money.

TJay74

So much inaccurate info in here it is not even funny. The stock LS3 airbox has no bearing on the maf readings anymore than the LS7 airbox does.

I had the LS7 one on my car with not one issue at all, sound was a little more throatier. Also if you want more airflow (CFM) then buy the ZR1 filter and filter retainer and install it. It flows more air the the stock filter the LS3/LS7 uses.

glenB

Your car, your money, enjoy