Just for clarity in regards occasional instances when we have deemed a 4bar FPR will be necessary for a particular modified 225 & its hardware (stock K04) if we are too >[/COLOR]
1. Extract maximum safe performance
2. Maintain well managed EGTâs
3. Avoid totally maxing the injectors out
4. Ensuring EGT protection management (fuel flood) is still possible. (Where applicable)
In regards the 4bar FPR itself & the stock pump, yes it will be tasking the fuel pump more than with the stock 3bar reg that is a given, & we do normally convey this when discussing the options. If its not going to be needed for an individual vehicles tune then all well & good, as of course there is no good reason to place any component under more stress unnecessarily.
The pump will cope with a 4bar reg + reasonable amount of boost providing it is healthy. Unfortunately as these vehicles get older in turn the pumps have also had a long life, & sometimes are already weak & sagging & in this instance fitting a 4bar reg would likely only expedite the pumps demise.
Will it be needed with a stock K04 + full set of popular bolt on mods like intake, TIP, DP, cat/decat, cat back, FMIC etc, well this is dependant on how much air the turbo is able to push, how much boost is asked for by the tune at higher rpmâs, & the tuners desired AFR.
We normally prior advise customers (in instances we think we might see a very high IDC) that we will review/log the vehicle with the stock fuel system before making the call on whether we are going to have to fit & calibrate for a 4bar to comfortably support our AFR targets.
If it can be avoided then we do avoid it (less load on the pump, less cost for the customer etc)
We are however also mindful to be sure the fuel pump is up to it in instances where a 4bar FPR is to be used, & measure/log fuel pressure if there are any doubts at all over the health of the pump.
Ideally it would be a better overall solution to fit & calibrate for larger injectors when the stock injectors cannot flow enough with a 3bar reg, however costs are obviously quite a bit more with this route.
Hope this helps.
Regards
Morgan