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mpampis_
25-04-11, 12:34
hello again guys, i have two important question to make you, so i would be glad if anyone know some things

1. what is the max fuel pressure that we can rise? i have a walbro 255lt fuel pump and stock injectors (iw055)

2. the second question is about remaping. does anyone change the WOT enrichment. i read some things tha i found here http://www.berlinasportivo.com/pages/hexmaps.php#WOT

please reply to me
thanks

jimnielsen
25-04-11, 22:32
Hi Mapis. I am using the same walbro fuel pump (and also the standard pump in tandem). I am using the standard fuel pressure regulator to deliver approx 50 psi static pressure and up to 75 psi pressure under boost.

the problem with changing the WOT values in the standard map is that if you are using the standard injectors but are trying to get additional power by increasing the boost table values, you will already be maxing out the injectors before you get to 1.35bar - so there is no headroom in the injectors for additional WOT enrichment..

mpampis_
26-04-11, 12:33
Thanks, I understood what you say. As i saw the WOT enrichment table about 4000 - 4800 rpm it is 23% . after these RPM it is 10% , 6% and 0% . I just wondering if I could increase the enrichment to 25% to all rpm brakepoints after 4000rpm. I have a boost controller and I boost to 1 - 1,2 bar turbo boost.

When you say 50 psi, you mean engine running at idle and the vacuum hose on the regulator unplugged?

jimnielsen
29-04-11, 00:06
Hi Mpampis - yes, 50 psi measured with the ignition in the on position BUT the car engine is OFF. The WOT table has extra fuel between 4000-4800 rpm as this is where the engine is most susceptible to detonation damage. You can easily change the values in the table if you have a wide band lambda sensor to see the results - but its easy to drive the standard injectors to 80% duty cycle - their max. The demand for fuel increases as revs rise so the car will demand more fuel at 6000rpm WOT than 4000 WOT. keep a close watch on the lambda sensor as damage can occur quickly if you run lean.

jim

MaxiBoost
29-04-11, 05:17
Q4 injectors IW058 not IW055

mpampis_
29-04-11, 08:23
I meant iw058. I am writting by phone so I make mistakes. Jim thanks for your answers. The point is tha I would like to make it a bit more rich, I have an innovate wideband with lamda, so I guess if i will make the wot enrichment table a bit more (ex 1.10) after 4800 rpm that the stock is 1.23 I will be a bit richer isn't it?

jimnielsen
30-04-11, 09:50
I think its a good idea, but just because you can put values in the WOT table does not mean that the fuel system will be able to supply the required amount of fuel. Increasing the static fuel pressure will help but you cant go to far..

jim.

mpampis_
30-04-11, 20:11
i know jim. i think in the injection table the max label is 17.32 ms which it means about 80-85% of injectors. that's why i thought if i increase the wot enrichment at high rpms (that in stock is 6 - 0 %) it would help in adition with increasing fuel pressure. at least to run stock injectors at their limit. i would like new injectors but is bad moment now, so i'm trying to limit the stock ones :)