I know that most people put their MAF sensor in the intake pipe, has anybody put it in their IC pipe instead? and if so how does your car run and idle? and what size IC pipes are you using? Any input on this would be great before we drop all the new turbo stuff in

 

You can run the MAF sensor on the charged pipe. It's call a blow-thru MAf setup. We will be running it on our TA turbo setup.





MrC

 

hey Mr. C!!! long time no talk. thanks for the reply and pictures. the tc is looking sick my friend! I was going to pm you, but I thought I'd make a post incase others would like info too.

first of all... have you guys tuned your tc yet a/ the maf in the charge pipe? my wifes car is a daily and my main concern is how the drivability is. I dont want a rough idle, or idle surge, I dont want it to stall after a wot pull! with the maf in the intake pipe, there are minimal things that cab affect it, but a friend pointed out to me that with the maf in the charge pipe there are many more factors that cone into play since the sensor is located after the fmic, bov, and most of all, air is pressurized passing thru the maf.

I just wanted to ask questions before I went and tried it myself.. I thought I might beable to limit the amount of headaches I get lol

 

Clay, good to hear from you. To answer your question, yes we have tuned a tc with a blow-thru(BT) MAF setup. The idle, wot, roll on, off throttle, etc is not affected if tuned properly. One issue one might run into with the BT MAF setup is on certain MAF sensor, the temp sensor element on the MAF is very fragile and using it in a pressurize setup can damage the MAF sensor. However, with the tC's MAF sensor, we have dynoed the car with the BT MAF running up to 12 psi (290whp-Dyno dynamics or ~325whp-dynojet) without any issues. We will try to test it beyond 12psi once we finish up our TimeAttack tc's turbo setup.

Regardless of where the MAF sensor is mounted (before or after the turbo), on a boosted tc generating beyond the high 200whp (DD), you want to clamp-down on the MAf sensor voltage around 4.6-4.7 volts, and from there tune it off a pressure sensor (MAP), otherwise the factory ecu will go nuts.

There's two main reasons why we opted to go the BT MAf setup route on our turbo setup:

- We're running a BOV setup and having the MAF after the BOV will not cause the engine to run pig rich when the BOV vents (off throttle).

- We're running a 4" cold air intake system. Mounting the factory MAF sensor on a 4" tube is not going to meter the air too accurately. Also our cold air intake tube is mounting below the front bumper and relocating the MAF sensor will require wiring in a plug extension.

Of course you can't just change the MAF sensor from a draw-thru to a BT setup without retuning the car. And the diameter of the charge pipe where the MAf sensor is mounted on will change the tune from car to car, i.e. if you are running the same turbo setup as your buddy (same turbo, same boost, etc.) with only the difference being the diameter of the MAF charge pipe, your fuel map will be different than your friends.

But again, until we finish up our TA tc and dyno tune it with the MAF sensor beyond 12 psi, we won't know what issues we may run across with this setup. We will try to get some numbers for 16psi, 20psi, 24 psi, and beyond with this setup.

MrC

 

I am interested in the MAF in the charge pipe. I initially didn't think it would work because of the design of our MAF, but I can see the benefits of having it in the pipe, especially being after the BOV. I'd be really interested in hearing your experiences after more tuning and how it differs from being located in the intake pipe.

 

interesting topic, i've been searching about this thing for a while.. but we'll see how our maf stand the pressure in the charge pipe