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Message: [QUOTE="TARM, post: 1424308, member: 578"] There are other effects to increasing VOP PSI. When VOP goes up the later the injector opens, and the shorter Injector Pulse Width (read: ACTUAL TIME, NOT REQUESTED TIME that the injector is delivering fuel). It creates a delay. I know Nate and I am sure Swamps and other injector manf tested these and while you noticed a difference in the idle sound they did not see benefits in power or off idle performance. I am in no way saying that on the street and certainly at certain PW and ICP the b code cannot outflow a hybrid. For that matter a given set of parameters an A code can beat both of them all things being equal. It would not make much of a difference as it would not net you much but still A codes can tech outflow the others at certain a set of conditions. One issue is you can only put so much CP and thus tq to a engine before you rip it apart not to mention you can only use so much power a given level or your just spinning your wheels. You have to widen the RPM band and that means as you need not only fast injection rate itself for say a single pulse but you need decreased time to get the injector primed to fire again. As that time shortens the A code goes from first to second and then to last. The B code goes from second to first and then to second again. The hybrid goes from last to second and then to first. B codes based on this are sort of middle of the road. That could and can possibly be a good thing for some people. Actually many street trucks that is if they have big oil. The nozzle size also comes into play as well. Because as the limiting factor moves away from the nozzle as it gets bigger it puts more demand on the oil side. Say a hybrid and B code with 100% nozzles. The B codes are going to win as the nozzle is still the limit on flow not the oil. Move to 200% and we are just past the tipping point. Move up past that and hybrids are clearly pulling ahead. The faster the fuel can flow thru the nozzle the faster the oil side has to move. In an ideal world the nozzle would always be the point of restriction limit and we would always have as much flow capacity for a max fuel pressure as needed or any injection system. This in part why CR blow the doors off and at the same time and drive like stock with a tune change. With our HEUI the oil at some point as PW shrinks can not keep up with flow rate to keep pressure up to drive the piston down fast enough for the given time and thus you get lower injection pressure which translates to less fuel being injected. This eventually happens to all of the injectors just at different PW ICP demands. The hybrid can make it the farthest before it hits this limit as its has the lowest hydraulic ratio. The hybrid is a bit harder to tune ( more to alter from stock). ICP ramp up etc.. Not that it can not be done easily it just that it takes more knowledge of ICP to PW etc at low demand levels etc and abit more tinkering. Thus tech B codes are easier to tune but to get a hybrid to flow the demands of a B code you increase ICP and ramp up for the PW at the lower demand levels / broader PW. This negates the advantage of the B code ratio for better fuel pressure injection. But it takes tuning to do it. You can not take tuning for a hybrid with 200% nozzle switch to B codes same nozzle size and call that a fair comparison. Both need to be tuned differently and the hybrid will be the most effected as its farther away from the stock A code ratio. It all comes down to what is going on the oil side. The pressure drop from and time to fill effecting piston speed and then time refill again. What people forget is if the engines both have enough HPO ie big oil then there are not HUGE differences between B codes and Hybrids flow rates until nozzle siz gets larger. But then at the smaller nozzles you can go with less hpop if you are going hybrid. There is far more variation in each trucks setup that would mask any comparisons IMO on peak HP etc until you pass 200% threshold from what I have seen reported. Maybe peak RPM HP and TQ are made at but again this assume tuning that was well worked out on both to push thing to the max. Best done on a engine dyno with only injector swap and tuning changes. B code can make great injectors especially on a street truck but if we are talking about which will give the best perf a hybrid wins. Once you get into the 300-400% nozzle size the hybrid pulls away clearly. Another thing it seems some people ( not speaking of you 96F350KID) is that the injector capacity does not indicate in any way how much fuel is actually be used other than it can not be more than the capacity. It should always be less as its not good to set injectors to fully empty. Thus just because a person has 400cc injectors does not mean in anyway that is what they are injecting @ say 2ms pw. I hope no one honestly thinks my 200% 465cc are actually injecting 465cc LOL Maybe in 4+ms :doh: Its was done for other reasons and possible later nozzle swap. Another thing to consider is the HP vs TQ levels made with B codes vs hybrids. What tq level stock rods could take before coming apart? That is another area why its better when you can fuel up high as it means lower CP and TQ for a given peak HP rating. Think of the TQ and CP it takes to make the same peak HP number at 2700 rpm vs 3700 rpms. Just an example not real numbers. When you can fuel higher you can hold fueling down lower keep CP and tq lower as you can keep fueling up top extending the power band which nets more HP. Here are a couple posts by HRT and one by Charles that say it way better than my ramblings and bumblings... [url]http://powerstrokearmy.com/forums/showthread.php?t=4087[/url] [url]http://powerstrokearmy.com/forums/showthread.php?t=4087[/url] Quote from Charles that I think gives a good basic explanation of the issue and what is happening on the oil side and thus why we actually get better perf if we drop hydraulic ratios. Do not forget that we have control over ICP pressure and at low demand times we can offset the difference of hydro ratio with increase ICP. [/QUOTE]