Needswings - yes - note - we're talking 17+ psi case - not everyone.
In ref to the stock pump - as per Post#4 ....technically very likely - especially with a blocked fuel filter or aging pump.
Your years of experience helps confirm this.


Takeaway from this - When adding even a 65mm pulley - at least change your fuel filter!


Unfortunately as per Post#4 - the 255 Walbro will only satisfy at stock 56psi pressure - if you up the pressure to 5bar - it too doesnt have the legs for higher than stock boost. I was very suprised at this. But again your wealth of experience may add some light to this finding.


I'm currently looking at the SL55 pump which is "HUGE" in comparison - pulls heaps of amps and wastes alot of the enrgy back in the recycle.
One option there would be to possibly trim the pump input voltage to 11.5-12V instead of my stock 13.5V. I understand the SL55 does this with a unit dynamically on the go (GG may still have one) - but I'll just settle for a set volts reduction. My calcs indicate 11.2V should do it, but I'd probably go 11.5-12V. Could be another add on to purchase!