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Ok, well i've been fiddling with the boost settings on my car a little over the last few days. I've got a ProfecB...great little unit by the way. Now basically I've managed to adjust things (mainly the sharpness control) so I get full boost @ 10psi by 3,500.. its great.

Running past that to 12-13psi it will do it, but it doesn't seem as "solid" and takes much longer to hit full boost (around 4,500), so its a lot less streetable. Then again it would probably need proper dyno S-AFC adjustments to get the most of that setting, as last tune it was pretty much tuned to 10psi.

Now basically @10psi it holds that rock solid right through to the rev limiter, not dropping from what i can observe on the boost guage.

My main question - is there any disadvantage to having such a broad power band all the way between 3,500 -> 7000rpm? Am I actually losing heaps of power this way? It seems fast :cheers:

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naw.... EBC is connected up correctly.. stock boost solenoid is completely disconnected.

ok, what i think i meant to get at that at 13psi it doesn't seem as strong as running at 10psi and it takes longer to spool up so is there any point running 13psi at all? but of course its hard to tell without a proper dyno reading where the peak power is really being developed.

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Probably b/c your A/F mixtures get screwed at higher boost.

A related exaple (not entirely the same though):

I was running 11psi before I tuned my SAFC, and obtained a max of 164rwkw. After tuning te SAFC to obtain near perfect A/F ratios, I got 200rwkw on 9psi.

Basically what I am trying to say is that the ECU will more than likely richen your A/F ratios as boost increases, so, there is a trade off between boost / A/F ratios.

If the car feels better at 10psi, then just leave it there for that reason. If you want to increase boost, then think about a SAFC, or aftermarket management.

Zahos

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