Converting MAF to MAP

[Keyan]

I'm considering doing this to my car. A couple reasons because: I want to be able to blow off atmospheric, my MAF sensor is shot, and when its raining or humid out, my MAF shorts out, reading as if it's sucking in much more air, and that coupled with the unichip, the ECU dumps fuel and the car doesn't idle and throws a system too rich code.

I did a search and found that mahonroy has also done this swap. Does anyone know if he got the rich idling issues fixed, and if he kept this swap or switched back to MAF?

I have a loaded intake manifold sitting in my garage, I have the parts to do it. I just need to double check the voltage range of the sensors and of how the operate, and I may do this swap next month.

Thoughts?

[KeWLKaT]

You will need the ECU and possibly redo wiring.

If you want to blow off you just need to put the MAF in the charge piping after the BOV...

Comon keyan, you KNOW it's not worth it.

[yamaha]

Mahonroy did it, but I don't think he ever updated us with what happened. All you need to do is put the MAF sensor in the chargepiping after the BOV. That would be loads easier and your MAF won't be dirty. Your main problem is your in New Jersey, and running it through the firewall, a big nono especially for boosted cars.

[KeWLKaT]

Errr yamaha, I thought you did it on your rd?

[yamaha]

I run mine after my BOV and before the intake manifold. I run my aircleaner in the engine bay too.

[Keyan]

MAF sensor in the charge piping is not an opition for me, alpine kit piping is 2" and the MAF is 2.75" there is no room for me to shove in in there, plus going from 2" to 2.75" and back down to 2" is not good at all for readings of the MAF.

[KeWLKaT]

MAF sensor in the charge piping is not an opition for me, alpine kit piping is 2" and the MAF is 2.75" there is no room for me to shove in in there, plus going from 2" to 2.75" and back down to 2" is not good at all for readings of the MAF.

So instead of just redoing your piping for 80$ you want to buy an ECU, map sensor, wiring, dozens of hours of frustration, and possibly a setup that doesn't work afterwards?

Wow, Keyan, your (non-existent) logic stuns me.

[Keyan]

So instead of just redoing your piping for 80$ you want to buy an ECU, map sensor, wiring, dozens of hours of frustration, and possibly a setup that doesn't work afterwards?

Wow, Keyan, your (non-existent) logic stuns me.

and your inability to read stuns me, as well.

i have already mentioned in this thread that i have an entire loaded non-cvvt inake manifold sitting around. also, mahonroy was able to run the MAP sesnor on his stock 04+ cvvt MAF ECU. Also keep in mind NGM is now doing ECU reprograms and can reflash my ecu with the values of the MAP. Also keep in mind that the MAF in the charge piping will most likely get different readings and (may) require a re-tune on the unichip.

[Mahonroy]

Thought I would post a little insite on this as I've tried to do this.

From what I could tell I was able to splice the MAF wires correctly into the MAP wires. What I noticed was the signal was a lot different. The MAF sensor voltage increased as air intake increased, and when I converted to the MAP sensor, it worked the same, it was just shifted up (or down I can't remember). So I know I got the signal wires good. Its possible if I swapped out the ECU's and tried it, it would have worked perfectly I don't know. Oh and another thing. I later gave that MAP sensor to Dave as his needed to be replaced, and the MAP sensor I was using ended up being faulty. So its possible that it would have worked all along and that I was just doing my experiment with a f**ked up MAP sensor.

[Cypher]

Damn, now i feel bad that it was faulty! At least it was free right ;)

[BColeman]

Keyan, it would be highly impossible to swap the ECU's from a non-CVVT motor to a CVVT motor, due to CVVT. You won't have any activation of it if you swapped ECUs. However, the reprogramming sounds like a good option.

Like others have mentioned, the MAF between the IM and BOV is ideal, while still retaining the sound of the BOV. But, like you mentioned, you are dealing with a piping size issue.

I would recomment replacing the piping from the IC outlet to the IM with the proper size pipe to accomodate your MAF. It is not unheard for the charge pipes between the turbo and the IC to be one size, while the piping from the IC to the IM is a different one. As a matter of fact, most WRX/STi's, Supras, etc. use this. It's not only because of space requirements, but I would venture to say it "slows" down the velocity of the compressed air a little. That could be a good thing, or a bad thing, depends on how you look at it. But since the MAF will be in a "blow-through" position, "slowing" the velocity down would be a good idea.

Of course, if you opt to do the piping on the cold side, you'll want to replace your MAF since you have already been having problems with it.

[Mahonroy]

Thats what I did. I have 2.25 pipes running from turbo to intercooler inlet, then 2.75 pipes fronning from intercooler outlet to the throttle body. Having the MAF in the charge pipes and the BOV inbetween the intercooler and the MAF. Works great so far, only issues I'm having is getting the clamps tight enough around the MAF, because you don't want to tighten it down so much to crack the plastic, but if not enough the pipes keep blowing off under boost (though only of had this problem above 22psi). I was going to weld on a bracket to hold the two pipes together around the MAF to eliminate this problem.

[Keyan]

i am stuck using an alpine 5th injector elbow which is 2". i already have a 2.25" pipe with my BOV on it that goes to a reducer, to the alpine elbow.

[BColeman]

Vibrant Performance sells the weld on type clamps that will hold the charge pipes together. I'll look for them on their site and add the link to this post.

On struck1481's ride, we used the T-Clamp style clamps on the MAF, and so far so good. In the very beginning, we seemed to only blow the couplers off the intercooler or the IM, never the MAF. But we were using cheap worm gear clamps at those locations. Now they are all T-Clamp style.

Boost Clamps (http://vibrantperformance.com/catalog/index.php?cPath=1022_1036_1213&osCsid=239abf6b53789205f18c1332280c3d7a)

[Mahonroy]

Yeah I have every clamp in my turbo system using the stainless steel T-clamps.

http://www.jattus.com/Performance/elantra_img4.jpg

I found the vibrant ones:

http://vibrantperformance.com/catalog/images/12640_WEBL.jpg

http://vibrantperformance.com/catalog/images/12642_WEBS.jpg

Only thing is it would cost me $110 bucks for them which is a little steep when I can do a similar thing out of home depot parts for under $15. Does look pretty sharp though

[BColeman]

Yeah, I agree. You are basically paying for the quick disconnect feature and the polished stainless steel.

You can definitely go cheaper with Home Depot stuff, and it can look just as good to. But it's the idea that counts.


Keyan, now I understand why you can't really do anything with the piping. That 5th injector does pose quite a problem for piping. And getting a 2.75" elbow and attempting to weld in a spot for the injector would be a major PITA. It is possible, but for DIYer's, it's too much trouble.

[KeWLKaT]

...or just upgrade to real fuel management? lol