Positioning & Orientation of MAF

[Stephen Hackett]

Put this down to the enthusiasm of building over reading instructions...

I installed the MAF last weekend on the Allan recommended air intake tube (Spectre Performance Air Intake Tubes 97291 - Free Shipping on Orders Over $99 at Summit Racing), and was very happy that I was smart enough to hide it by placing it (a) close to the throttle body and (b) installed it on the bottom of the tube - so it's not really visible - see pic attached

Only afterwards did I read the GM instructions where it says to place it in (at least a horizontal position or closer to the top) and place it a min of 10 inches from the throttle body.

My question - Has anyone installed the MAF in a position like this and does it really cause issues with the engine (it's an LS7 by the way)?, or should I just bite the bullet, cover up the current hole, and relocate the MAF closer to the filter and higher up on the tube.

 

[Will Campbell]

I don't know about the orientation, but I suspect that has to be correct.

As far as the length is concerned, the guide lists the distances that are optimal for the tune in the ECU. But I understand that a knowledgeable tuner can compensate for this, and make it work.

The problem with getting too close to the TB is probably reversion, which confuses the MAF, and so the computer. So you shouldn't mount it too close. How much is too close? I'm guessing not too far off the recommended distance from the TB...

If it were my car, I'd get a new tube and mount it where it needs to be. Probably cheaper than welding, better looking, and no worries about laminar flow being interrupted.

 

[Scott Rowland]

In a perfect world, you want the maf about 12+" away and in clean airflow, so not super close to bends either.
Horizontal positioning is so that condensation is not able to create a puddle and give false readings or short it. But, I assume that to be extreme weather testing.

 

[Stephen Hackett]

Thanks guys, I'll get a new tube...guess it was overly optimistic to pray that someone would post a "no problem, I've done the same thing hundreds of times and it works better than the factory recommended positioning"

 

[Shane]

Yeah....I would also recommend moving it away from the TB. Be sure to use the recommended intake pipe size also....which should be 4" I believe. On GTM's we normally run a CAI that elbows off the TB, then runs to one side of the engine, and then forward along side the engine and then angles over to one of the side scoops for fresh air. We normally install the MAF in the center of the straight pipe that runs along side the engine as this always turns out to be the longest stretch of straight pipe in the system. We have had no problems so far. We have had a few customers who mounted their MAF right at the TB like you have done and have ran into hours and even days at the tuners trying to "tune out" the problems that this creates.