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Fuel pressure regulator?

Posted: Thu Apr 02, 2015 12:24 pm
by falcor
What kind should I get for my 914 ITB conversion? I'd like to avoid the cheap tuning store chinese stuff.
I really dont need any adjustability, a set 3 bar regulator would be fine, is there anyhing usable from a standard car?
I would prefer hose inlet/outlet connectors.

Re: Fuel pressure regulator?

Posted: Thu Apr 02, 2015 1:05 pm
by Steve Arndt
Stock bus type Bosch from an L jet model work. Easy to mount and very robust.

Re: Fuel pressure regulator?

Posted: Thu Apr 02, 2015 1:11 pm
by andy198712
Steve Arndt wrote:Stock bus type Bosch from an L jet model work. Easy to mount and very robust.

any like that on 90's 2000's cars? just thinking for ease of finding at the scrapy or parts shop

Re: Fuel pressure regulator?

Posted: Thu Apr 02, 2015 5:51 pm
by Piledriver
Places like Summit/Jegs sell 2 versions of the Bosch Djet adjustable regulator, use with or without manifold vac reference port.
(basically a modified adjuster screw, looks like it comes with both)

MSD branged, but is a proper Bosch regulator, down to the correct part# for Djet.
Usually a ~20-45 PSI-ish adjustment range
http://www.jegs.com/i/MSD+Ignition/121/2222/10002/-1

Re: Fuel pressure regulator?

Posted: Thu Apr 02, 2015 7:19 pm
by Steve Arndt
L jet Not adjustable (easily) like a d jet but already at at 2.5 bar, hose fittings, vacuum referenced, and super affordable (plus they last 40 years). Same with Vanagon regulators but they have two in and 1 out. Makes for a balanced fuel rail flow wise.

Re: Fuel pressure regulator?

Posted: Fri Jan 08, 2016 12:34 pm
by Thorkhild

Re: Fuel pressure regulator?

Posted: Fri Jan 08, 2016 5:34 pm
by Piledriver
MSD #2222 is a Bosch DJet regulator with a vacuum/pressure tap adjustment screw.
Very good mechanically adjustable, vac/pressure compensating regulator, genuine Bosch.

Summit and Jegs seem to have discontinued them, probably cutting into their profit margin on the blingy units that don't last.

They are all over Ebay and many other sources.

Re: Fuel pressure regulator?

Posted: Fri Jan 08, 2016 10:01 pm
by falcor
I ended up buying the Bosch unit that Mario sells. It doesnt say what pressure it holds tho?

Re: Fuel pressure regulator?

Posted: Fri Jan 08, 2016 10:38 pm
by Piledriver
Its the same Bosch unit I suggested.

Can be turned down below 26 PSI and up to ~45, maybe a tad more.
That's just the baseline adjustment, the boost or vacuum reference can move it from that centerpoint.

Re: Fuel pressure regulator?

Posted: Sat Jan 09, 2016 1:21 am
by andy198712
Should you connect the vac line for NA use or just plug it?

Re: Fuel pressure regulator?

Posted: Sat Jan 09, 2016 1:23 am
by falcor
For NA motors you just leave it open to athmoshperic pressure I guess?

Hmmmm, I'll need it to be at 3 bar....so almost borderline on the high side then.

Re: Fuel pressure regulator?

Posted: Sat Jan 09, 2016 11:06 am
by Piledriver
andy198712 wrote:Should you connect the vac line for NA use or just plug it?
Never plug it, just leave it open to ATM so it can correct for variations at least.

You can do it either way for NA, but hooking up manifold vac as a reference is more technically correct.
Accels may be easier to initially tune without it, but you should leave accel off (or at least EAE off) until the VE table is well tuned, or the corrections multiply garbage.

Re: Fuel pressure regulator?

Posted: Sun Jan 10, 2016 9:13 am
by andy198712
Cool :)

Re: Fuel pressure regulator?

Posted: Sat Jan 30, 2016 6:44 am
by falcor
Do I have to mod the bosch unit for it to be adjustable? I hooked the pump up directly to the battery (inline 10A fuse) and the pressure gauge reads 4 bar... ?! From what I read it shouldnt even go that high?

Re: Fuel pressure regulator?

Posted: Sat Jan 30, 2016 11:32 am
by Piledriver
falcor wrote:Do I have to mod the bosch unit for it to be adjustable? I hooked the pump up directly to the battery (inline 10A fuse) and the pressure gauge reads 4 bar... ?! From what I read it shouldnt even go that high?
There's a screw and a locknut, that adjusts it.
The hollow screw doubles as the vacuum port.
I found tuning was easier with fixed pressure and never bothered hooking it up.
DJet used fixed pressure.
Thats a modified DJet regulator. (well, the screw with vac port is the mod)

You may just need to adjust it.

Make certain you don't have a kink in the return line.

Not sure what fuel pump you are using, but a great many will go well over 100 PSI dead headed.
If you have a roller cell (044 or friends) 160+ PSI is typical, they are flow rated at 90 PSI.

The regulator is supposed to dump anything over its setting back to the tank.

A regulator installed backwards is like a plugged return---no flow.