1.5Bar on those turbos with no gearbox mods is still bye bye gearbox. 660 is the proven safe limit - which looking at the compressor maps is about 1.3 bar until 4,500. That said, depending on the wastegate control ports 1 bar is always enough lowdown and build from there with a good ignition map.1.5 bar capped in low rpms will still be very quick I suspect. Yes reading loads re how to reduce lag. It seems plenty can be done through valve timing.
According to Ben my turbos are ok to 1.8bar. That will be the very max I run higher up the rev range.
That COBB stuff looks very complex and intuitive. hope its as good as it sounds
I am not sure how much control COBB gives but I intended having different boost limits in different gears to aid traction. The new COBB stuff may negate the need for bespoke limits?
I know I have a 4.6 but you know what - its a biach at breaking things.