Well, he's in good hands and I know you got him taken care of. I didn't mean to confuse the situation. I wouldlike to hear more about the FPR and what you've done to tune these systems. I'm not sure exactly how this VAF system works....I always assumed since it uses a flapper door to measure air flow that it has a better abiliy to compensate for mods, as opposed to Speed Density. Many guys have used the adjustable spring/gears on the flapper door to adjust the AFR. I imagine this would be a global adjustment, but I don't know if it would have much or any effect @ WOT. It would be great if you (or anyone else "in the know") could lay down some tuning knowledge on this sometime.
I didn't realize I had any copies of any early dyno runs I did. Here is one from a few years ago. This run was a fuel pressure test ONLY. Run 1, 38 PSI. Run 2, 40 PSI. Run 3, 42 PSI. As there is no effective way to adjust the fuel curve with the OE Denso EFI, this illustrates small changes can have a real effect. As you can see, the saying "Lean Is Mean" shows here. The leaner curve made more top end HP but made less torque. Also the "Snatchiness" of the tune is noticed in drivability as well as in the wavy power curve. You will notice that just a small change in FP satisfied the engine. Tho losing a small amount of top end HP it improved peak torque & average torque considerably & was also much smoother while driving. This also shows the VAF function. If you look at the AFR potion of the graph, you will see that, contrary to popular belief, the VAF is not linear in its function & works more like an on/off switch. You can see the VAF flips open near 4500 RPM & richens the fuel curve for WOT operation. At that time, the only things done to this engine were an intake, mild port work & a header.
I really prefer a phone conversation as it allows a more fluid dynamic, where at the end "you" understand what I can do for you & I understand what your expectations are in a span of just a few minutes. Sometimes thru e-mail this process seems to take days at a sentence at a time.
Matt and old man once told me that "unrealistic expectations lead to unrealistic resentments".
I have often said that "words on a piece of paper are at best 2 dimensional. They have little tone and less reflection as to the authors true intent. It is left up to the reader to decide"
I think that we, collectivley, and way too often, believe that we have made clear what we wanted later to find out that we were not clear at all. But we still believed that we should have gotten more with just one change to the engine. You have made a difference in the world of the "pea-shooter engine". I like the baby step approach myself. I, for on am very appreciative of your skill and know how.
OK.....so given the relative on/off function of the VAF meter, adjusting the spring tension on the flapper door would not have any effect on AFR, but rather change the RPM point at which it switches over to enrichment???
OK.....so given the relative on/off function of the VAF meter, adjusting the spring tension on the flapper door would not have any effect on AFR, but rather change the RPM point at which it switches over to enrichment???
i cant wait to see this high compression piston rod kit all made up. just the though of having some super tight squish for us fuel economy guys. i think that with the stage 3 head would be sick to mate some propane injection with. how sick would that be? full duty cycle lpg running in your engine.
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