4 bar fuel pressurre regulator

1. stueyp Infrequent Poster Joined: Mar 2009 sunny old blackpool Posts: 153 Zafira gsi, saxo vts, mk2 golf 20vt

   #1 15th December 2010, 08:25

   is it worth getting a 4 bar fuel pressure reg on a VTS that just has breathing mods? will it make any difference to performance?
2. yr51ocw Frequent Poster Joined: Oct 2005 Posts: 751

   #2 15th December 2010, 08:37

   it will overful the engine on WOT and reduce performance and fuel economy
3. axsaxoman Saxperience Forum Bum Joined: Jan 2003 Scotland Posts: 3380

   #3 15th December 2010, 09:03

   no it won,t won,t --not if lambda control system is operational ,it will probably help idle +cold start and make it more responsive on acceleration ,
   once above 4k there is no closed loop on the ecu ,only then will it allow more WOT fuelling ,which quite often is all that is needed when fitting fast road cams,
   the extra difference of having it remapped is small and if money is tight you may consider not to be worth the money it costs for a remap .
   this all on the presumption that the car is running perfect now and you are not trying to solve another problem by lifting fuel pressure
   i would use a 4.5bar unit

   1 user thanked this post: stueyp
4. stueyp Infrequent Poster Joined: Mar 2009 sunny old blackpool Posts: 153 Zafira gsi, saxo vts, mk2 golf 20vt

   #4 15th December 2010, 11:04

   what does WOT mean?
5. stueyp Infrequent Poster Joined: Mar 2009 sunny old blackpool Posts: 153 Zafira gsi, saxo vts, mk2 golf 20vt

   #5 15th December 2010, 11:06

   Quote:

   Originally Posted by axsaxoman no it won,t won,t --not if lambda control system is operational ,it will probably help idle +cold start and make it more responsive on acceleration , once above 4k there is no closed loop on the ecu ,only then will it allow more WOT fuelling ,which quite often is all that is needed when fitting fast road cams, the extra difference of having it remapped is small and if money is tight you may consider not to be worth the money it costs for a remap . this all on the presumption that the car is running perfect now and you are not trying to solve another problem by lifting fuel pressure i would use a 4.5bar unit

   so fitting it wont cause it to overfuel etc?
6. ryanmt Established Member Joined: Oct 2004 Warrington Posts: 1987 AX VTS 57 3.0 TDI A5

   #6 15th December 2010, 11:23

   it will cause more fuel to go in past the injectors for the time they are opened so in that sense it will over fuel, except the lambda sensor will detect its over fueling so reduce the time the injectors are open to compensate. So whenever the lambda sensor is operational and trimming the injector dwell it will not be over fueling
7. bengtt5 Regular Poster Joined: Oct 2010 bournemouth Posts: 272 ph2 clio 172

   #7 15th December 2010, 12:35

   you can get a 3.8 bar one from vauxhall for the the vectra b 2.6 v6 engine which fits straight in for £26
8. axsaxoman Saxperience Forum Bum Joined: Jan 2003 Scotland Posts: 3380

   #8 15th December 2010, 16:21

   std unit is 3bar or 3.5 depending which saxo /106 you have ,so difference in fuelling will be small using a 3.8 bar one--no point
9. axsaxoman Saxperience Forum Bum Joined: Jan 2003 Scotland Posts: 3380

   #9 15th December 2010, 16:22

   Quote:

   Originally Posted by stueyp what does WOT mean?

   Wide Open Throttle
10. RustySkull Saxperience Post Whore Joined: Oct 2009 Basildon And Corringham, Essex Posts: 5179 MK1 Focus RS, Discovery TD5, Renault Trafic 2.0

    #10 15th December 2010, 18:18

    I was thinking of getting one too, this helped me out too
11. bengtt5 Regular Poster Joined: Oct 2010 bournemouth Posts: 272 ph2 clio 172

    #11 15th December 2010, 19:02

    Quote:

    Originally Posted by axsaxoman std unit is 3bar or 3.5 depending which saxo /106 you have ,so difference in fuelling will be small using a 3.8 bar one--no point

    im guessing its for his vts which have 3 bar as standard
12. welshpug Saxperience Forum Bum Joined: Jul 2010 South Wales Posts: 3078 ZX 16v, 205 GTI, 309 Goodwood, 405 MI16.

    #12 15th December 2010, 19:44

    utterly pointless without re-mapping
13. user_39613 Established Member Joined: Dec 2009 Essex Posts: 1006

    #13 15th December 2010, 20:41

    It will overfuel, the ecu will not be able to trim the fuel enough to compensate, so ultimately all you'll get from it is borewash.
14. bengtt5 Regular Poster Joined: Oct 2010 bournemouth Posts: 272 ph2 clio 172

    #14 15th December 2010, 23:23

    use to do this with vauxhall 2.5 v6s they have a 3 bar as standard if you put a 3.8 bar one on it was fine (got rid of flat spots etc)
    a 4 bar one would over fuel
    what about a 3.5 bar from a vtr