I am building an intake for my LS3 in a 64 impala and need help on MAF location. I read the LS3 EROD PDF and it shows it being 6-10" away from TB and level. Is this correct? Thanks in advance for the help.

 

If you can put it in the middle of a straight run of your intake tubing, it would be the best. People have put them in all locations. but it works best if the air flow has a straight run in and out of the MAF.

6-10" would be ok.. I have seen it right in front of the TB or even a foot or more away.

 

So being level doesn't matter? Just a straight run will help me out more than level.

 

IMO.. yes.. but it would not be the 1st time everyone slam me for being wrong ... LOL

But it wouldn't hurt to try and put it level. from what I have seen on other swaps is that many are not always level.. a few have even been Vertical !

By putting the MAF right after a bend, the air flow would be turning and would be causing turbulence, that would cause bad reading (?). Some MAF have screens in them to straighten out the air flow before it gets metered.

BC

 

You also may want to make sure that the Cooling Fans dont blow at the MAF. We were speaking to GM Powertrain guys at SEMA about MAF locations and the cooling fans came up. They said that testing showed issues with the blade style MAFs when they were hit will air from the cooling fans. Not sure how big the issues were, but food for thought. I would think that having more laminar flow from a straight section of pipe on either side of the sensor would be more critical as BCZEE stated.

Jon
PSI

 

Thats silly

Cooling cans blowing on the MAF housing would just cool the case a few degrees. Doesnt have any effect on the moving air inside of it because its not there long enough nor does it have ample surface area contact to cool the charge

 

What the GMP guys were trying to say was that the air buffeting the outside of the sensor could vibrate the sensor at a really high frequency (undetecable to your eye) to a point that it would screw up the readings. Again I am not sure how much credence I put in that (seems overly sensitive), just conveying what they said. But then again, if it is possible, just clock the sensor 90-degs so it isnt in the airstream.

FYI, I agree that the thermal conductivity of a Plastic MAF housing is low enough for Cooling Air impact to be negligible on cooling air passing inside the air intake.

Jon
PSI

 

The vibration aspect makes sense to a point. Kind of odd they think each pulse of air from a fan's blades make more of an impact than say the engine's harmonics, esp if the car has something solid mounted, or a tire out of a balance

Back on topic, I agree the MAF needs to be in the middle of a strait section. Older MAFs with screens could get away with bends more, but the new card styles, esp in aftermarket housings dont have such things

 

So I don't have as much room as I thought so what about a short tube(straight) like 4"-5" long then the filter?

 

If that is what you have, go with it and see how it runs.

Jon
PSI

 

What do you think of going to a smaller tube size like 2.5" or 3"? The TB is 4" but I have tried 3 different filters and all are too high or to long!