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Discussion Starter #1 (Edited)
Hi,

My boost used to drop from 22+psi to 15-16psi before 5000rpm and the torque followed the boost curve. Now with the new BNR WGA and retune the boost holds consistently over 21+psi over 6000rpm, but there is no more power top end. With the retune the stock injector duty cycle is up from 85%ish to over 95% sometimes and knock retard is up to highest of 14° which seems to be random too, usually about 6-8° here and there. There has always been KR but it has increased about 50%.

Any ideas why I'm not making more power? The only thing I can think of is the stock injectors can't keep up with proper fuel flow.

Can the maxed out injectors be causing the high KR too?

I have also recently installed a ZZP catless downpipe and ported the intake manifold. Max torque has not increased from before (over 220ft-lb (300nm) measured in EFILive) but the boost lag has reduced significantly. I also have the AEM CAI installed and NGK BKR7E V-Groove (Aussie version of V-Power I think) gapped to 22 thou. I'm running 98 octane BP Ultimate and after adding octane booster the knock retard didn't seem to change.

Also, the old tune still drops the boost to 15-16psi before 5000rpm. And the new tune with the OE WGA causes the boost to "wobble" at peak boost so the wastegate would be opening and closing repeatedly very quickly.

The timing is chain is a bit stretched so I'm wondering if that could cause false knock too.

Any help would be greatly appreciated.

Thanks,
Muz...
 

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so they upped the boost on standard injectors and never said they would need uprated , what size are the standard injectors and whats the fuel pressure on this car ?
 

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Discussion Starter #8
so they upped the boost on standard injectors and never said they would need uprated , what size are the standard injectors and whats the fuel pressure on this car ?
ZZP website says stock injectors are 33# and I have read that they are 26 or 24LB. Also I think the fuel pressure is 43.5psi. And no advice about needing upgrade...
 
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