Yep, based on further research, and what others have said above, a non 'rising rate' reg is linear, a 'rising rate' reg is non linear.
OK lads, just to clear up. Linear rate FPR's are just that. Thy reference to manifold and the delivery pressure rises with boost and FALLS with vacuum in a proportional, and linear fashion. 10psi boost results in 10psi extra fuel pressure to maintain a constant pressure differential across the injector nozzle A rising rate fpr works in exactly the same way but the fuel pressure rises, and falls according to its "rate" or ratio. as above, say 2:1 give 20psi fuel pressure for 10 psi boost. Whats important to note when thinking to use a RR FPR is that not only does the delivery pressure rise according to its rate with boost but the fuel pressure FALLS below ambient at the SAME rate when into vac. .So -7psi in the manifold gives a 14psi drop in fuel pressure from "base" So you get a disproportionate drop in fuel pressure when going into vac resulting in significant enleanment below ambient and enrichment above ambient. So its not so simple as to get a bit more fuel up high to compensate for small injectors when you LOOSE extra fuel when going into vac. Varying spray patterns and so-on...no thanks. Ill give it a tune!!!! E "
Tass, just for my information (and cause I am too lazy to work it out myself) Ambient atmospheric pressure absolute is 14.7 psi An NA engine with zero PSI in the manifold (14.7 psi absolute) IE: flat out. You then back off the throttle and it starts to pull vacuum. What would be the typical value of absolute vacuum that the engine could create in the manifold?
Thats the reg in my photo. Its an adjustable version of the stock reg. AND yes its 1:1 rate. I got it to fit OK with a bit of fiddling. That photo is actually that reg on my car.
Finally someone posted this up in clear english lol. This I didn't know though Is this common for all rising rate regs?
So I have been thinking it may be easiest to run two sets of oxygen sensors and switch between them for "power/economy" ???
How is that going to work???? O2 sensors only work in the closed loop portion of the map (low revs/low load) and the only ones I have seen are for stoich of 14.7:1. Buy Nistune already and stop faffing about.
I think its a good idea. I want to see a full write up with pictures and results! Should be fantastic!!
Not 100% sure to be honest. This is why I post question. But I would base it upon either modifying, somehow, the sensors. Or switching between sensors that give different readings. I thought open loop was only during warm up. AFAIK, with a Holden, open loop is only during warm up. So O2 sensor has no effect on power output and/or track driving?? I'm starting to think more along the lines of running piggyback ECUs. Nistuned or whatever. I get more help than I need here. :thumbup: :rofl::rofl::rofl:
No, open loop is everywhere other than low load/low revs. O2's have no influence on 'proper' driving. Nistune is not a piggyback, it's a simplified method of modifying the OEM tune within the standard ecu. Far better than a piggyback IMO.
