fmi does not have a bung for me to connect my mbc

[chavez408]

I recently purchase a fmi from punishment racing, and I realise that this fmi does not have a bung for me to connect my mbc. What do I do? I know I am not suppose to tap it to the bov line. Other than the wastegate, where does the other line go to now? Am I going to have to weld a bung to the j pipe or lower pipe of the fmi?

 

[TSiAWD666]

Yeah pretty much. You could drill a hole, tape, and use a barbed fitting that threads but that will of course screw in quite a bit into the airflow path. Also the threads might not hold very long depending on how thick your piping is, and they may not seal well either.

 

[talon187]

i know they say its not the best way but me and all my buddies just put a t off the intake manifold line going to the bov ive had no issues

 

[chavez408]

What kind of t fitting did you use? You got a link? Iv been to home depot and they have nothing!
Pretty much your tapping into the bov, right? (Talon187)

 

[MrBoxx]

Do NOT tap into the BOV line. This causes more problems than you'll ever realize.

The proper place to tap is on the lower intercooler pipe or the compressor housing. Drill and tap your J-pipe/IC pipe, thread in a barbed fitting that you can get at any auto parts store, and use teflon paste or tape to seal it. Some people even use a little JBWeld to seal it permanently.

 

[chavez408]

Thanks. Do you have a link for the procedure for this? Like how big the drill needs to be, and what kind of fittings people use. Thanks a lot, again eric.

 

[MrBoxx]

Most people use a 1/4" or 1/8" NPT brass fitting if I remember right, so a tap that size is needed. The drill bit used should be a fraction smaller than that.

Oldman recommends putting it as close to the J-pipe entrance as possible, that way you can get inside with a dremel tool and try to cut as much of the protruding fitting as you can from inside, thus reducing the flow disruption that the fitting causes. While it's easy enough to do, I wouldn't think it would cause as much of a problem as it's worth on a street-driven vehicle. If the car were balls-out dragging every weekend, sure, cut it off. But I wouldn't lose sleep over it.

 

[chavez408]

Does the fitting need to have two opening? I guess I will be PM oldman real soon.

 

[forcefed4]

These work great, not too bad of a price if you don't want to drill and tap.
FTG-QuickTap-CompHSG: atpturbo.com

 

[MrBoxx]

Why would it need two openings? You're going from the IC pipe/compressor housing to the MBC to the Wastegate Actuator. That's it. It's the simplest setup and it won't interfere with your BOV's operation, like teeing it's vacuum line would do.

 

[talon187]

i dont know if i like that idea... why how much damage can it do if you tap in at the bov ?

 

[MrBoxx]

An MBC is essentially a boost leak. You don't want a boost leak on your BOV line.

Taking the pressure source from the j-pipe fitting has many benefits.

1. The main reason why alot of mbc instructions and some tech articles suggests to tap from the BOV line is because it's connected to the intake manifold, the argument is that this is more accurate because it's the same pressure the engine sees. In reality this is a non issue because the boost gauge is tap to the intake manifold no matter where you tap your mbc so there is no advantage in tapping the bov/manifold pressure as previously thought.

2. The proper functioning (opening and closing) of the bov depends greatly on the accuracy of the pressure in the vacuum hose you're thinking of tapping on or off boost so it's best to leave it connected directly to the manifold without any interference.

3. Tapping off the compressor/j-pipe offers the shortest vacuum hose route which greatly reduces the chance of boost spike.

4. In the case of boost leaks, tapping off the compressor/j-pipe will help prevent over boosting the turbo.

5. Hooking up a bleeder type mbc like the TurboXS standard mbc to the bov line will result in a vacuum leak as well as affect the working of the BOV.

 

[chavez408]

These work great, not too bad of a price if you don't want to drill and tap.
FTG-QuickTap-CompHSG: atpturbo.com

That looks good. Would that work for my IC pipe? How does it work... it doesnt require drilling or tapping?? You just mount it?

 

[chavez408]

http://www.nexternal.com/hombre/images/barbed.jpg
So this would work, boxx. With a 'close' bottom. I am thinking of tapping It on my lower pipping since I am still on the stock 14b but I am upgrading soon.

 

[MrBoxx]

Yes, either of those will work, assuming the barbed end is the same size as the rest of your vacuum line system.

 

[chavez408]

Ok good. See, I always thought the other end (not the end for the vacumm line) had to be open. But I guess it works if its close.

 

[MrBoxx]

The threaded end is hollow, not closed. Air passes completely through that fitting. At least, that's what I'm assuming you're questioning.

 

[chavez408]

Yes sir, you got it. Kudos!