Obx fmu

[bhearts]

So I purchased an obx brand fmu last week, as soon as it got in a tore it open. For how inexpensive it was 85 dollars, I feel like I got a quality piece. I ruined the lower diaphragm/fuel restricting disk. But that's my own fault. So I traced it's shape on the bottom of an altoids can and cut me out a new small metal disk. Seriously not kidding, it's installed and fits fine, very similar thickness metals so that helps. I also had previously purchased a vortech brand 3:1 recal kit, with the help of a little sandpaper I made it fit. It wouldn't write go over the bolts that hold the lower metal piece, so I took a little metal off the part that I got in the kit. We'll see how well that altoids tin holds up to corrosion, but I don't question that it's strength and flexibility are fine. uploadfromtaptalk1405631815988.jpg

[bhearts]

Heres a crazy idea for everyone running an fmu. Running the boost reference to it from different sources. Like right at the turbo, or up in the intake manifold. With an intercooler in line, you could see 1lb of boost difference between the two spots. So if you were previously running lean and referencing from the manifold, you could reference from right at the turbo and give yourself a couple extra pounds of fuel pressure. Has anyone tried anything like this?

[sketchman]

Looks fine. A mechanical FMU is a hard thing to do make badly I would think.

That's an interesting idea - reference point. You could T into the WG line like you do for a bleed valve/MBC to get the most accurate ref possible.

[Rocketman]

Always pull after the intercooler - different temps will cause different pressure drops across it. This can cause different boost levels depending on ambient conditions

I would get a replacement diaphragm for your FMU - those disks are finely calibrated. Altoids tin is cheap steel with a painted on coating

[bhearts]

Always pull after the intercooler - different temps will cause different pressure drops across it. This can cause different boost levels depending on ambient conditions

I never ever could have come up with that on my own. I'll let you guys know that I'm going to run two pressure gauges, one at the turbo, one at the manifold, for the most accurate running possible. Rocketman, in theory cooler ambient temps would cause greater pressure drops. That's great knowledge. But I would assume the difference is dismal. I read that 90 degree elbows can drop as much as .3 psi.

[Flyin4stroke]

I'll sell you a new fmu in da box. $30.

[bhearts]

o no, thats tempting. what ratio is it?

[Flyin4stroke]

Not sure. Got it with some other stuff I bought. I'm on ms so it just sits around.

[bhearts]

hey guys i need some help. what do i use in place of my stock fpr, for a bung to hook a hose to?

[eurotiva]

why are you getting rid of your stock fuel pressure regulator?

[sketchman]

Pretty sure I measured that hole the stock FPR sits in, and you can tap it with a NPT tap. Not sure on the size. 1/4" maybe. Then you can just screw in a NPT to barb adapter and hook an adjustable FPR up with hose.

[bhearts]

Yeah i got an adjustable fpr. I'm putting in b6d injectors

[eurotiva]

Ahhh i see, sorry I'm a noob.

[bhearts]

i know dickmeyer offered a oem styled oringed replacement for when you bought his fpr. that has to be something i can purchase online. or at mcparts

[bhearts]

fuel pressure regulator.jpg