hhrfreek I was trying to decide if I should just modify the K&N intake I have, or install the MAF in the cool charge pipe. It looked to me like John GM tech used the same size pipe as stock. I could be wrong. Though I couldn't see how that would work with 29lbs of boost that he was running. Pictures are hard to tell actual size.

 

I am aware of how the MAF measures the air. When I say boost...I speak in generality because thats what most understand.

Moar Boost = Moar Faster

LOL

Moving the MAF to a 2.5 could work at whatever the air flow is at that level, but you lose resolution as you approach the top of the maf scale then you really have to rely on the MAF correction table.

I absolutely love tuning in the cold side. It is way easier. If the MAF is in the intake its measuring air ~8ft away from the engine? So in a WOT transition, the fueling is rich because you are fueling an amount of air that has not made it to the engine yet. So the trims pull fuel but usually over shoot then you have a slight lean correction to trim. This does not happen with the MAF relocate because its measuring air less than 2 ft from the engine. That is my theory anyway. Ive learned/theorized a ton of goofy stuff by relocating the MAF.

 

 

What I meant is for all of the folks that don't understand. The MAF measures how much electricity is needed to keep the heating coil at a set temp as air flows over it.

The "Hot Wire" section of:

https://en.wikipedia.org/wiki/Mass_flow_sensor

Just an interesting technical tidbit. It explains how those rip-off "tunes" work, with a $.02 resistor.

 

hhrfreak nice work. Sounds and looks like you found the right size pipe to maximize the resolution of the MAF for your combo. I too intend to move my MAF sensor when I do my swap.

Look at your MAF at idle to make sure it's flat lined and steady, what I have found when going to the larger (4") tubes with the card style MAF is that the air needs to be flowing as straight as possible before getting to the MAF.



With my Impala setup I have a honeycomb airflow straighter Honeycomb Airflow Straightener
the the pipe end just ahead of the MAF. Prior to me adding the straighter my MAF signal was moving all over the place at lower and idle flow rates.

Moving the MAF does make a lot of sense, the only drawback I see is that also moves IAT 1 as well so any inefficiency of the IC at higher boost and air loads will show as a higher IAT 1 temperature. There is one table that we have available to help but who knows what other algorithm they may be using that temp in, and, maybe I'm suggesting something that isn't even issue in the whole scheme of things.

 

The single wire type of MAF must have laminar flow. That means straight line air flow, no turbulence. And be correctly oriented.

I don't know if the computer wants the air temp before or after the intercooler. My wild guess is just as it enters the TB.

 

Nice job hhrfreek!!!

 

The SS has 2 Air Temp sensors, one is the MAF sensor the other is the TMAP sensor after the intercooler.

 

As does ours on temp sensors, one in T map and one in the charge pipe. I have watched all 3 temp sensors to see how underhood temps effect intake temps. Then it's nice to see how well the inter cooler is working. Even though the temp sendor in the maff does help the PCM to figure how dence the air is, I don't think it makes much difference. Once your fuel trims are dialed in your gold.

 

I have used straighteners in the past. Actually used one from Saxon on my stock intake on the Solstice with very good results before I relocated.

I was having an idle issue caused by the blow off. On my old tubes, the BOV was maybe 6-8" from the maf. I thought by moving up over 12" away and around a bend the air would be smooth enough when it hits the MAF, but it still wasnt. BOV cracks open just a tad at idle from vac and causes an erratic idle. I was hitting about 10 MAF cells for idle and it was not steady. I installed a straightener right after the BOV before the bend and it cut down to 5. I coated the spot where I was going to put it with a little RTV and slid it up the pipe into place. Thought I'd try this before chopping my new tube and putting in a coupler before the MAF. Works good even with it before the bends pretty far from the MAF.

Also the light flywheel makes idle the most difficult, I think. I'm betting if I had the stock fly like before, I wouldn't even have to correct the fluctuations at the MAF because the RPMS would be a lot more steady. Even turning on the lights, fans or turning the steering wheel drops the idle a couple hundred rpms sometimes. It always recovers without stalling though. A LOT more drivetrain noise is heard from the clutch too without the stock dual mass. I had a light flywheel in my HHR and noticed no difference in noise.

Just thought I'd share some things you could run into or notice.

I was able to get about 300 miles on the car over the past 2 weeks. I did some pulls last night at 15lbs and it felt great. Really moved along for such low boost. Changing the oil this weekend and cranking it up to 28-30.