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CKATM wrote:Thanks for clearing that up.

So with installing a larger MAF, do I just enter the new frequency outputs in the Mass Flow tables, and everything else takes care of itself (more or less) ?

Larger Injectors, enter new figures in Run A/FParam ?

So I could see the Open Loop Air Fuel Ratio V's RPM is the target fuel ratio in open loop, so which tables set the target fuel ratio in closed loop ?

There is a MAF table calculation spreadsheet around that you will want to look at (in the VT A5 thread from memory).

There is an injector flow rate scalar for adjusting the injector size, once that is correct you adjust the injector rate vs rpm vs mgc to make the commanded A/F ratio (the on that the PCM thinks it is outputting) match the actual measured A/F ratio via a wideband. you should leave the A/F ratios alone until you have dialed in the injectors because the ratio won't be correct.

target A/F ratio in closed loop is stoich, closed loop uses the narrowband o2 sensors which are only useful to tell if you are rich or lean of stoich, they won't tell you how rich or lean.

Thanks for that Charlay,
I'll have a look at those tonight.

Hey Guy's,
I've been a bit busy, sorry.

With all that we've been discussing with larger MAF's and adding extra flow tables, are we talking about me going to a VT V6 PCM, or can I stay with the VS PCM ?

Cheers

Holden202T wrote:yeah 1 bar map sensor = 14.7psi negative pressure, from there 2 bar is 14.7psi positive, 3 bar is 30 psi positive etc.

yep 1 bar map is 1 bar relative to the vacuum of space more or less.

So a complete practical vacuum is 0 bar (ie in space) and the atmosphere is 1 bar of pressure at sea level.