Notices
928 Forum 1978-1995
Sponsored by:
Sponsored by: 928 Specialists

FPR Question

Thread Tools
 
Search this Thread
 
Old 03-31-2018, 02:26 PM
  #16  
Adk46
Rennlist Member
 
Adk46's Avatar
 
Join Date: Aug 2014
Location: Adirondack Mountains, New York
Posts: 2,420
Received 318 Likes on 166 Posts
Default

What’s inside a damper? I’ve been imagining a spring and a rubber bladder. What happens without them? I understand that there must be a significant “water hammer” sort of thing, since the injectors all open and close at the same time, but is it strong enough to break something?

And is vacuum used to control a regulator or damper? I thought I read that the vacuum is just to remove gas from a small leak.
Old 03-31-2018, 04:29 PM
  #17  
FredR
Rennlist Member
 
FredR's Avatar
 
Join Date: Jun 2005
Location: Oman
Posts: 9,926
Received 764 Likes on 609 Posts
Default

Originally Posted by Adk46
What’s inside a damper? I’ve been imagining a spring and a rubber bladder. What happens without them? I understand that there must be a significant “water hammer” sort of thing, since the injectors all open and close at the same time, but is it strong enough to break something?

And is vacuum used to control a regulator or damper? I thought I read that the vacuum is just to remove gas from a small leak.
Curt,

In a certain sense the regulator and the damper have the same basic objective in that both of them seek to maintain the fuel rail at a specific pressure relative to the inlet manifold but that is where the similarities start and stop. The regulator is needed to position the pump on its curve such that it pumps at a constant flow rate and it does this by reacting to the steady state fuel rail pressure. The response, although reasonably prompt, is not a fast response loop. The dampers on the other hand are trying to control resonant pressure fluctuations caused by the reaction you mentioned and thus the dampers need to respond much quicker to smaller variations and thus are at the other end of the control spectrum or so I understand. If the regulator was effective as a damper there would be no need for dampers would there? The system needs to keep a constant differential pressure between the fuel rail and the inlet tract in order to ensure the amount of fuel delivered for a given injector opening time remains constant thus the vacuum lines supply the reference pressure the regulator and the dampers respond to.
Old 02-29-2020, 09:23 PM
  #18  
928928
2nd Gear
 
928928's Avatar
 
Join Date: Feb 2020
Location: Tallinn
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
Default

Hi. I have Euro 86 16V i.e. same setup as above, 2 FPR, 1 damper. That damper is leaking fuel to vacuum a bit. Need to find a new one. Bosch stopped production of 0 280 161 008 in 2019 I think.
Any ideas where could be Bosch NOS or Porsche's 928 110 202 00 available for not too crazy price? Also, could I use 928 110 202 01 which is for the 32V engine? Any othe ideas? Thnx in advance.
Old 03-01-2020, 08:20 AM
  #19  
C531XHO
Burning Brakes
 
C531XHO's Avatar
 
Join Date: Jul 2015
Location: Dorset
Posts: 836
Received 108 Likes on 71 Posts
Default

Originally Posted by 928928
Hi. I have Euro 86 16V i.e. same setup as above, 2 FPR, 1 damper. That damper is leaking fuel to vacuum a bit. Need to find a new one. Bosch stopped production of 0 280 161 008 in 2019 I think.
Any ideas where could be Bosch NOS or Porsche's 928 110 202 00 available for not too crazy price? Also, could I use 928 110 202 01 which is for the 32V engine? Any othe ideas? Thnx in advance.
see post #10?..
Old 03-01-2020, 08:27 AM
  #20  
928928
2nd Gear
 
928928's Avatar
 
Join Date: Feb 2020
Location: Tallinn
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by C531XHO
see post #10?..
That's years old post and I don't need FPR's but an fuel damper. His webshop has the right thing available @$415, too high.



Quick Reply: FPR Question



All times are GMT -3. The time now is 11:42 PM.