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Fuel Pressure Regulator

Idle isn't where the fuelling matters though - that's full chat, full boost where the head gasket (at best) is at risk if it's wrong...

Still, the 3.8 bar should be rich if anything which is the safe way to go if you aren't going to be running ideal mixture.

Anhow, what does the ECU do if it sees rich mixture (as Tony asked)?

These cars run cats as standard (and have to in the US to pass 'smog', so Danno's chips will be designed to retain that) so must have closed loop emissions monitoring or whatever. The ECU should correct fuelling to 14.7:1 or whatever is ideal stoichiometric (sp?). Since a 3.8 bar would overfuel then the ECU could correct that back - the danger would be underfuelling which the ECU can't correct if 100% duty cycle on the injectors isn't enough.
 
That was kind of my origional thinking about going for the slighly higher pressure rating, running slightly rich at the end of the day will produce abit more emmisions, but i asked about the ECU altering the fueling to suit if it was at slightly higher pressure, cant remember what if anything was said.
 
And what happens on the non cat UK cars that dont have a lambda sensor?

I think I am going to try the S2 / 968 part (I have one on order), but put in an A/f ratio meter so I dont run it either too rich or too lean for long (if this looks bad I will go for some sort of adaptor Hose for my guru supplied (3.0 bar labelled) FPR - I may also go for the lindsey fuel rail gauge (got to be usefull for fault finding anyway a nice visual check on fuel pressure) and a boost gauge. So next question is other than demon tweeks who does a nice A pillar 2 gauge pod?
I am getting married on Friday though so don't expect any immediate developments I have plenty of other stuff to keep me busy this week and next [:D][:D][:D]


Tony
 
Come on Tony get your priorities right. Only takes a few hours to get married, you could get back into the car in the late afternoon. Ok ok take the whole day off but get things moving the next day then. Don't our cars have CATs anyway, I know mine is pre 92 but I thought it would still have a CAT.? [;)]
 
My '89 does not have a cat (decatting was an option when new) and also does not have a lambda sensor so cannot correct if it runs rich, and guess what?

When I had it dyno'd the operator did say it was running slightly rich. I have no figures but the car did not noticeably use any more fuel after chipping, and the tailpipe does not get covered in black soot though it does smell rich. Ideally I too want to fit an AFR gauge before I start tracking this year, just so I know everything is ok, but I will have to sort out a lambda sensot and connecting it in first.

Incidentally it has passed MOT emissions quite happily with the kit fitted.

Tony - CONGRATULATIONS mate [:D][:D][:D], I hope you and Mrs Sidestream are very happy together (though you don't deserve her [;)]
 
Yeah, congratulations Tony.

I didn't know you were after a wife - I could've doen you a deal on mine [:D]
 
[:D]

Hopefully, further up the learning curve now, (still slightly confused by the higher pressure less fuel description on renlist) but I believe at full throttle the ECU ignores the lambda sensor and just relies on the pre-programmed map - that is why the AFM gauge doesn't swoop back and forwards and sits solidly at the rich (hopefully) end of the scale, where as at part throttle it sweeps back and forwards as the ECU constantly adjusts the mixture.

Tony

So I think I will just fit the guru supplied regulator with some sort of adaptor or my original hose with the end cut off (if it is long enough) better get started!
Its a shame as I assumed Porsche swapped to the threaded one for a reason, but never mind I can always go back to the S2 one when I get my DPW, MAP sensor and custom remap. (that would be sometime after my new cluitch, torque tube overhaul, gearbox rebuild, my new suspension and paintwork tidy up then i.e. not soon)
 
Just hurry up and fit the Guru kit, I'm getting impatient to hear how it goes with your rebuilt Turbocharger and monster exhaust [8D]

No pressure of course, but you've had the gauges on a week now [:D][:D][:D]
 
Well its not as far progressed as I hoped, wastegate is shimmed - and intake adaptor pipe shortened ( a job I have had waiting for a long time) . Most of the day was spent messing about with my Patrol which now starts - as Iwas trying to investigate the non-starting and sorting Yudra's Polo which had an annoying cold start problem. Oh and almost an Hour looking for a bolt I dropped from the air filter housing.

Tony
 
Well finished yesterday and done around 200miles.
The reliaboost (direct to wastegate) at its factory setting gave me 12PSI, a quick adjustment and I now have a peak of 16.5 PSI (right in the middle of the 15-18PSI) and it drops to 14 near the red line. Its is much quicker than before and I find I am often one gear higher than before fith now giving plenty meaningfull acceleration at 80. Almost too meaningfull a space opened up in front of me on the M27 so a quick squirt seemed to be in order - fortunately I was looking in the rear view mirror when the blue lights came on allowing a rapid return to 70 and the nice gentleman in the dark blue volvo carried on his way without a chat.
I think it might still be running a touch rich at high RPM, but will have the plugs out for a good examine tommorow. which brings me onto my next thread.
Tony
 
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