Rob,
The cams will move the VE of the engine to a higher rev range and hence the fuelling will require adjustment - reduce at low & mid RPM and increase at higher RPM. You will also be moving the peak torque point and hence the ignition timing will require adjustment.
From info I have heard and witnessed a knock of 35 correlates to the onset of very minor detonation, should be ok if it exceeds once in a while but I woudl not map a car to regularly exceed that. This number has been identified via det cans on a couple of vehicles now. It is however likely to vary between engine and knock sensor slightly.
When tuning to that level I woudl want to know that all of the fuel system is capable of providing enough fuel CONSISTENTLY, bear in mind all these items are now circa 10-11 years old. IMHo I woudl change fuel filter, fuel pump & either replace injectors or get teh old ones cleaned. Old tired injectors after 60-100K miles are likely to have started to hose rather than spray mist. With teh cams you are likely to spend more time up in teh rev range and hence my personal opinion is that you will run out of fuelling with teh 540cc injectors. The stock setup appears to be ok for upto 1.25 bar at high rpm according to thor. you could probably get away with running high boost in teh mid-band as injector period is longer here. I know Don has managed 340-345 bhp on stock injectors at circa 1.5 bar and IIRC he has seen 80% duty cycle at 6K rpm ish when running his regular 1.3 bar? (I am sure Don will correct me if I am wrong
)
I woudl change to larger injectors, new fuel pump (walbro or sytec or wha have you) and replace fuel filter. I would leave the stock FPR in place - IIRC the higher pressure you run injectors ta the more likely they are to lock. I woudl alos then get the car remapped - where - I dont know
(but all this is me and not you lol)
Good luck m8
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I didn't know Uz had sold his 'Four!? As to fitting the fuel system upgrades, well that depends on what you hope to be running with regard to power on this car after the re-map. If 350bhp or more then I'd say yes as even though really you ought to also be changing the injectors too, you could get round the immediate need for those by upping the fuel pressure a little so that the stock 540's are better able to deal with the fueling required at that level.
Since I'm still running the stock ECU on mine I would expect there to be "issues" if the cams could cause them, but since I have none I can only say that if they are correctly installed and set up/timed in then there shouldn't be any issues other than the need to adjust fuelling to optimise things as JP mentioned - this more than anything is why I need an ECU on mine....
