Looking for FI expert

[LVJimmy]

I'm looking to replace my MAF with one from a Corvette.The connector on mine is a 5-wire but larger than any of the corvette MAF's that I have been able to find. any idea on which MAF I would need to get. The engine is an '04 6 liter out of a GMC van. The engine is in a '70 Jimmy.

 

[Blue85]

Why do you need/want a Corvette MAF? What is wrong with the original? Why aren't other donors acceptable?

I don't know the answer to your question, but there is more to making it run right than just matching up the connectors. The MAF is an "airflow to frequency" converter, which has to be mapped with the same table inside the engine controller. So the ECU will probably need the table updated. If you use a larger MAF (is this your goal?), you may run out of bandwidth in the ECU to read the airflow.

There is a method where you use a frequency converter in-line withe MAF to rescale the signal. This is common to allow a higher bandwidth MAF to work with a stock ECU by reducing the frequency into a range that the ECU can read. However, this still requires a new airflow table in the ECU to scale the signal back up.

Of course there is no need for a larger-scaled MAF unless the airflow into the engine exceeds what the old MAF can measure. There is some *potential* benefit to a larger diameter because it *might* allow a little more airflow at high rpm, but generally it doesn't help at all unless the engine has been modified a lot (i.e. bigger cam and/or heads).

 

[Russell]

Those MAFs flow extremely well as is, you probably don't need to worry about changing it unless you've gone to forced induction or something similarly drastic...

As far as which ones will fit, anything from an gen III engine should technically fit, I was under the impression that all those MAFs were the same from a 3.1L to an 8.1L...

 

[LVJimmy]

Those MAFs flow extremely well as is, you probably don't need to worry about changing it unless you've gone to forced induction or something similarly drastic...

As far as which ones will fit, anything from an gen III engine should technically fit, I was under the impression that all those MAFs were the same from a 3.1L to an 8.1L...

I was under the same impression but it ain't so. I posted on LS1tech and no answers there either. The tuner who did the computer said some of the vans use the same connector as the LS2 MAF. Not sure if it's true but he is shipping a new connector. The reason for the change is mainly asthetics. The CAI was made for a 4" MAF now it looks stupid with the 3". The tuner has already changed the computer tables to run the 4"