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ST170 Fuel Rail Options?
wombat - 8/12/14 at 09:54 PM

Was going to use the standard ST fuel rail with the pressure thingy blocked off and an 8mm tail fitted to give a return, but now wondering if I should get a custom rail made?
Thoughts anyone?

Cheers

mark chandler - 8/12/14 at 10:17 PM

Why not just use the rail as designed and take the return back to the tank?

[Edited on 8/12/14 by mark chandler]

big_wasa - 9/12/14 at 11:15 AM

The st170 has no return or pressure regulator it has a damper. You could adapt the port for the pressure switch or I would see if a Black top rail will fit.

kingster996 - 9/12/14 at 11:23 AM

My Silvertop has a modified ST fuel rail - can take a pic if you want?

wombat - 9/12/14 at 11:23 AM

Damper !!! Thats the word I was looking for last night :-)

Following what someone else had done, I was going to blank off the damper, remove the sensor from the end of the rail and tap an 8mm fitting in the end.

Was thinking that a custom rail would probably have less risk of air leaks with a straight in/return.

Are you saying a blacktop rail is effectively just that?

wombat - 9/12/14 at 11:28 AM

kingster - picture always helpful :-)

DW100 - 9/12/14 at 12:26 PM

Something that would be really useful for people doing things like this is that some cars have a rear mounted fuel filter with built in regulator, flow and return to tank pipes, and a single regulated pressure line going to the front or the car and fuel rail.

I'll try and look up a part no.

Edit to say research shows the filter / regulator I was looking at operates at 6.4 Bar. Lower pressures are achieved by PWM of fuel pump using feedback from fuel pressure sensor.

[Edited on 9/12/14 by DW100]

kingster996 - 9/12/14 at 12:36 PM

This should show you the differences - std ST170 and modded one (with yellow hoses)




[Edited on 9/12/14 by kingster996]

big_wasa - 9/12/14 at 02:12 PM

Yep that puts into pictures what I mean by using the pressure sensor port for the return but what are you using to regulate the pressure ?

coozer - 9/12/14 at 02:34 PM

Like Kingster there I took the pressure sensor off, drilled right through and put a barbed fitting on blanking the outside off with a plate, all just to tidy it up and point the return back to meet up with the pcv.

kingster996 - 9/12/14 at 04:04 PM

quote:
Originally posted by big_wasa
...but what are you using to regulate the pressure ?

You can just see the pressure reg to the left of the modded fuel rail.

DW100 - 9/12/14 at 05:01 PM

This filter/Regulator for a E46 BMW could be useful if a little long.

BMW 3 SERIES E46 320 325 330 316 318 MAHLE ORIGINAL FUEL FILTER PRESSURE KL149

Description
Description


Regulated to 3.5 Bar (3.0 With Vacuum)

wombat - 9/12/14 at 06:25 PM

🍻 great stuff thanks, will stick with my plan then.
Thanks again.