Bigger Mass Air Flow Sensor

[shadowsniper3006]

LOL! ONLY 671RWHP and running 9's. Come on, that is just awesome! Congrats on hitting the 9's...that is quite an acomplishment.

 

Just my recommendation however have your tuner do a detailed 3bar COS Speed Density Tune. It will have all around better control of the fueling IMO. If done right, the car should have fairly good street manners and of course be an animal at the track.

 

i was thinking the same thing...only 671 RWHP and only 9's.....like i'll ever be able to do that....

 

Why is the MAF tune more street able? From what i have been seeing, with my truck, the MAF is all over the place at idle but the MAP is very consitant. What about one is more "streetable" then the other, and i guess deffine streetable, like idle quality?

[Warden]

Thanks guys.In my group I'm not really that fast.Actually.I know of a C5 that makes 600RWHP and runs 9.9s.Of course the car leaves like a bitch.I have added too much extra weight on the front end with twins,intercooler and an iron block.At 14#s I've a lot left but I need to get the car to hook.

I'll let Krambo explain the difference between a MAF and SD for steetability.It's not a huge difference.Idle,responsivness and normal driving seem to be better with a MAF.

I've had a lot of fun on the street with the car.With normal street tires I can spin them at 100 MPH!The first time I did that it scarred the shit out of me.I've owned a couple of 8 second cars but never really drove them that far on the street.Even with Nitto DRs this car is an animal on the street.I can't do anything under 60 MPH.I just bought an eBoost II and I'm going to dial the boost in for each gear.

Since I've bought the SS I've lost a little interest in the Vette.I'm sure when the weather breaks I'll be right back into it.

Thanks

[misterp]

...with my truck, the MAF is all over the place at idle but the MAP is very consitant...

 

The root issue is the type of device/instrument Delco chose to use to measure engine airflow - a hot-wire MAF sensor is perfect for measuring LAMINAR airflow, meaning airflow going across the sensor that is perfectly stable, non-turbulent, and flowing at a steady rate - and the MAF sensor works fantastic under these limited conditions. But when you have any form of turbulent airflow, or pulsing airflow, or airflow that reverses direction a couple hundred times a second then it is physically just not possible to use any kind of "hot-wire" instrument, no matter how 'precise' it is. The approach of using a hot-wire element device in attempt to measure turbulent airflow is just fundamentally flawed; Delco knows this, it's why the factory tune does not (mostly) use MAF readings until 4000-RPM - after that point assuming a factory camshaft and intake manifold the air going through the CAI tube and across the hot-wire inside the MAF sensor are known to be nice and steady and smooth and the readings from the MAF sensor reliable.

 

If you install an aftermarket cam that has enough overlap, you will have reversion meaning that the air in the intake manifold is actually reversing direction a few hundred times a second - as a result the column of air going through the CAI tube will not be flowing steadily into the throttle body, but rather be 'marching' or 'pulsing', or even vibrating like the air in the port of a ported speaker enclosure; under these conditions a MAF is totally helpless, it was never intended to deal with this kind of non-laminar airflow.

 

If you relocate the MAF to directly in-front of the throttle body (very close to the intake) then even with a factory cam it will see enough reversion to render it useless.

 

If you change the CAI plumbing and put a 90-degree elbow before or after the MAF then you will make turbulent airflow inside the column of air in the CAI tube, and that turbulent airflow will shoot the MAF in the foot.

 

If you install an IAT sensor immediately upstream of the MAF then you will also "install" turbulence in the air column, and it will affect the MAF.

 

On forced-induction setups - if you install a big-assed ATI bypass/blowoff valve just upstream of the MAF sensor, then you will cause major turbulence in the CAI air column and render the MAF useless (ask Zachm89!)

 

AFA driveability with MAF versus without MAF, this is my opinion - a vehicle should ideally run identically either way, if it doesn't then the tuner is not done tuning; the reasons for this are another topic but my point is, there is no reason to not expect great driveability manners & mileage out of a SD tune, on my own truck with my lame-attempt-SD-tune-in-progress I have stock driveability and mileage and it's totally SD (no MAF -or- oxygen sensors).

 

Mr. P.

[misterp]

...Even with Nitto DRs this car is an animal on the street..."

LOL yeah I bet!

 

...I just bought an eBoost II and I'm going to dial the boost in for each gear...

Exactly what I would do! I am very eager to hear how that works out.

 

Mr. P.

[shadowsniper3006]

Thanks Steve, my truck is also not running on the o2's and MAF and runs really good on the street (thanks to my tuner), so i didn't understand why SD was getting looked at like that.