VNAMVET

If it takes additional air AND fuel to increase horsepower, then(if this is true), how can just the addition of a Blackwing (or some other less restrictive air filter) increase horsepower?

I would think that you would have to "program in" more fuel, right? :confused:

sliderhss

I just installed my Halltech Trap last night and I can tell you that it made a very noticable difference. According to Jim Hall the computer will re-learn the new air flow within about 50 miles of driving time.

I have never done anything to my cars except change out the air intake systems. I have had 3 Trans Ams and changing the LIDS always made a big difference.

I will have to say though that this Trap has made a HUGE difference with no other modifications. I FEEL much more grunt off the bottom and across the entire power range. The sound of the engine is also much more bold when on the gas.



[Modified by sliderhss, 3:03 PM 2/1/2004]

Scott03Z06

The computer will compensate for additional air and adds in more fuel. Also I'm sure the Blackwing also lowers the entering air temperature. Remember that the density of air increases as temperature decreases (assuming all other conditions stay the same). If the air is more dense, then you have more oxygen per unit volume.

Cobra4B

:withstupid: Compared to the stock '01 lid the Vortex was a huge kick in the pants.

boss4zo6

I agree with Scott03zo6

VNAMVET

So it seems, up to a point. I have seen where many of those who use a less restrictive air intake, run "pig rich". Using that senario, iIt would seem as though that the "computer" does not really help, but rather hurt the fuel management system.

Does anyone really know "how" the ECM knows just EXACTLY how much more fuel to add? And why would GM program the ECM to know how to accomplish this procedure in the first place?

SQEZN BI

As everyone mentioned computer compinsates for added air flow. This is how a dry nitrous system works you inject nitrous oxide only to intake charge and computer takes care of the rest. I perfer wet system where you inject fuel and nitrous and if your mixture is off a little leave that to the computer. Those stock injectors can only flow so much though keep that in mind.

Painrace

Your engine is an air pump. The more efficiently you get air and fuel in and mixed and then out the more efficient the engine will be. Now that you have more air going in see what a set of long tube headers will do. You will love it. A Hypertech computer upgrade will also help performance and you can raise the rev limiter.

sliderhss

Can you tune out the slight tick that the LS6 has with any of the tuning kits?

ledfoot

Hmm...slight tick ? that's a new one

Your motor should be just fine. Have you taken it to the track or had it dynoed ?
If it's running 12.7-12.3 quarter mile times or pulling 354-360 rwhp on the dyno, I'd say your motor is fine.

You can always take it back to the dealer and have them perform a diagnostic test

However, these cars are so sophisticated that if something were wrong, your computer would've told you by now.

Jmo,

good luck! :)

David In Indy

Cobra4B

That tick is an inherent characteristic of the ls6 motor. You're hearing your valve-train. It's an overhead-valve motor with a a very agressive (for stock) cam. When I firt got it I posted about the noise b/c it concerned me too. My previous car (DOHC '97 cobra) didn't make any doises like that. If you add LT headers you'll hear the noise even more becuase the header walls are much thinner than the stock iron manifolds. :cheers:

Oyishdog

more air = greater combustion = more power You cannot ignite or combust fuel without o2 - pure 02 will actually combust in our atmosphere

cold air intakes work becuase cold air is more dense with o2 molecules - the more o2, the bigger the "boom"

GTB/ZR-1

Simple, the factory setup is on the rich side for safety--the aftermarket intakes just move the AFR up to more HP conducive #'s.
Example: factory AFR may be 11.5:1, where the aftermarket moves it to 12.3:1--therefore producing more HP on the leaner setup.
The only time you'll need to add more fuel comes when it the mixture becomes too lean...

lager99

Anytime you make a change to your car and run it on the dyno, you can see the changes the computer makes after a few runs. Many times your car will show worse performance when you change exhaust etc...and dyno, until 3 or 4 runs later after the computer has relearned. I think it probably still adjusts after that, but obviously you won't run 50 miles on the dyno. :crazy: More air, colder air, and lower altitude air, all work in your favor more more hp. :thumbs:

Scott03Z06

I would assume that the computer, by monitoring the O2 sensors, would know how much fuel to add or subtract. There are probably other sensors which help in making the decison.

VNAMVET

Well! It's all kind of coming together for me now and I understand, from your different viewpoints, how "more" air can make "more" HP..............

The part I cannot understand is HOW the engine management systems "know" that the engine is receiving more air from an intake rather than, say, from an intake LEAK? How come no codes are "thrown"?

Obviously, the systems that monitor the engine air supply don't the difference, do they?

WanganVette

Just adding fuel won't work because as stated before there is an optinmal air to fuel ratio (stociometric <sp>) that provides for full fuel useage without leftover air or fuel. This is the best horsepower producing tune.

Adding more air to this (BAD!!!) will result in detonation where it is no longer a burn in the cylinder but an explosion of sorts. This basically kills your engine real quick.

Adding gas to the mix results in a rich condtion. Cars are usually run about a point below stociometric for saftey.

The equation for power in a combustion engine is Air + Fuel = Power. So more air (free flow intake for ex.) will allow there to be more Air, the computer reads this via the MAF sensor and adds fuel accordingly. More Air + Fuel = Power. It takes a while to get all the little bits on how the engine actually works. Read up on fuel injection systems.

As for "air leaks"... If its before the MAF sensor it gets read like everything else. If it's after it's usually small enough for that "saftey margin" rich condition. But the factory puts in oxygen sensors in the exhaust which will let the computer know if it is burning lean and to add fuel or if it is rich and it should lean the mixture out a bit.

Hope that helps.
Jim

Sandra Bigwoode

bingo!

you have uncovered the dirty little secret of after market 'performance' parts for the c5 and the z06 in particular.

the fancy and very expensive air intakes, 'ported' tb's, colored sparkplug wires, 160 degree tstat's, x-pipes, really noisy cat back systems, etc, basically do not really add hp and in some cases actually lessen it.

a tuner once said about all this stuff, 'buy them for looks and buy them for the sound, but they won't add horsepower to your stock z06'.

your mass air flow [aka MAF] sensor will detect any increased airflow and signal the pcm to add more fuel, but the stock z06 air intake flows a *lot* of cold air already and you are unlikely to increase it by fitting an after market system.

the stock z06 is a well balanced car and you are unlikely to increase the power absent some major engine mods, ie, forced induction, major head cam changes, stroker or 6.0+ block kits to increase cid...

rbartick

Superbowl Halftime...

During closed loop operation (cruising) the PCM reads various sensors on the engine and determines what it thinks the proper amount of fuel should be to get stoich (14.7:1). A very important sensor in this "loop" is the MAF sensor at the front of the powerplant. In a perfect setup the PCM should detect the proper airflow (even with an aftermarket airbox), inject the proper amount of fuel, and get a perfect mixture. The O2 sensors monitor the exhaust system and provide "feedback" to the PCM. This feedback tells the PCM how close the delivered mixture was. If the O2 sensors report rich the PCM will reduce closed loop fuel delivery with negative fuel trims. If the O2 sensors report lean the PCM will increase closed loop fuel delivery with positive fuel trims.

So if you run a new airbox, get more air into the motor, and the MAF properly detects it you will get more air & more gas into the motor. This should result in more power. If the MAF does not properly read the incoming air with a new airbox (which happens very often) the PCM will not really know how much air is entering the engine. The result is the initially delivered mixture is off and the PCM corrects with fuel trims. If the fuel trims are off by a lot the WOT open loop mixture can be affected. This is where PCM tuning really helps.

If you have an intake or vacuum leak the PCM's initially delivered mixture will be much too lean. The PCM will see this from O2 sensor feedback and it will compensate with positive fuel trims. The PCM will set a DTC and turn on the Check Engine light if the positive fuel trims are maxxed out and the O2 sensors are still reporting lean.

Game on, gotta go.

lager99

:skep: I disagree...I've dyno'd after installing a Blackwing, after LT headers & cats, and after Bullet exhaust. Every one showed a gain. :chevy