I've looked at the so-called facts from dyno runs where IR set-ups are compared to any numbr of EFI set-ups. On, say, Boss or World/TFS Windsor based V8's, EFI systems that have single or dual throttle bodys are most definately produce a better 'Simpsons rule' or 'RMS' style area under curve from off idle to maximum rpm. So the total engergy released on an EFI engine can be superior. It's like a stereo, Route mean square or between the peaks. Which one is best is based on if your 15 or 51, listening to the beat of Basement Jax, or the Robert Plants high range. An EFI mapper worships area under the curve, and some engine builders are into as much power for as little revs as possible. Its like Lary Perkins said when talking to Street Machine Hot Holdens article back in 1990. A 308 with 460 hp at 6700 rpm beats 462 at 6900. When he said that, I latched on to the fact that if the engine is sitting at 6700 rpm all day, its 2.5% more efficent, and under 2.5% less load than an engine at 6900 rpm. He then said the engine that makes 500 hp with the least fuel is the more efficent race engine. Everything is based around brake effective horsepower at the rev range its being used at.
When a butterfly or slide throttle set-up like Motech is used, torque is sacrificied, and some of the lowend area under curve is lost for good, with a gain at the top end. When mechanical or converted to EFI systems are used (Hilborne etc), then the EFI profiler tends to link the ingition in with the package, so there is a full quota of fuel and ingition optimsation.
When going to AVESCO set-ups, with slide throttle and injector postion far away from the stock EFI set-up, peak power is again imrpoved, and low end claibration becomes very difficult. The engineer then applies more science to the whole power curve to get some kind of driveaility to the pits or 40 km/h drivability in the pits..
When you look at the IDA Weber versions of the same Windsor engines, then they yield class leading power at the peak rpm because they size the carb to the given curve, then optimize. Area under the curve is probably less, power peak is often more. The ignition systems are often separated like in the bad old days of TransAm, so effective engine mapping is 'fuel only, by Weber', not a linked fuel and ignition set-ups like we are seeing.
Once made, a modern EFI system is type cast, and the injectors and inlet runners are fixed. On most DCOE/DHLA/DHRA/IDA set-ups, tuned length , carb position (elevation and runner lenghth) can be easily changed.
On Motorbikes, a similar situation exists, where the EFI set-ups are employed due to modern constraints. Mapping a engine takes an age. In the old flatside Mikuni world, more power is there at the rpm peak.
Anyway, I've not been hard working enough to do what you've done, so my asserations are based on other peoples evidence. I read automotive agony columns, where people relate their calibration problems, and the focus of my attentions are V8's and fours. I've been immersed in doing 5th order polynomial regressions on experimental data, and I believe that an engine is just a pump which can recieve modulation form the EFI system. I think that the EFI system cannot actually create any extra power, even if the EFI system has inlet runners which have no 13 to 30% restriction via venturi, its CV or conventional 3 circuit Weber workalike counterpart will eclipse it.
Any way, the solution set for the function of a function I've listed above has been a 5 year problem for me.
I've used residential mapping to create a lookup table of data sets for road roughness and chemical applicator projects, and have come up with valid selections that are easy to implement by a computer. I'm not anti-Electronic per se, I just don't like putting scala values into some boxes like GM's cal pak set-up, it makes you think your controlling the VE table. You not, your obtimising fuel delivery by pulse width. I've been bitten by that bug twice, and recon that a lot of wrong thinking comes about from just working out which lever gives you a good result, when its better to find out why on a one alteration per test basis.
With electronics, there are serveral ways of getting good results which are actually wrong. For example, Mitsubishis fuzzy logic Magna transmission, and the torque demand optimisation system where ingition and throttle are performance inputs (David Vizard discussed this in 1983 in his Ford SOHC turbo work, on how to degrade spark to control torque rise)
The solution for the above IR Carb "function of a function" is not to integrate dy over dx, but to map a 4000 to 10000 rpm table in 100 rpm steps, and vary the Ln's Y intercept scala co-efficients as a function. I've done that many times in five other major projects. You are then forced to understand how the engine responds to inertial ramming, in a manner like Fords F3 EEC graph. You are creating a 3D Autocad relief map of an engines air supply needs.
Inertial ramming in an Independent runner engine is the reason for the changes in co-efficent. I'll post it when I've mapped it. It is an example of what I like about electronics.
With as much respect as I can muster, I'm certain the realtionship between venturi and rpm and cylinder size is a heck of a lot simpler by eliminating VE.
If I'm wrong, I'll just copy what you do, after I've worked it out, but I'm certain 40 years of engine research brings into relief that an engine is just a pump, and we tune to the air supply, we don't have to think VE all the time. VE is going backwards to go forwards, in my opinion.
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When a butterfly or slide throttle set-up like Motech is used, torque is sacrificied, and some of the lowend area under curve is lost for good, with a gain at the top end. When mechanical or converted to EFI systems are used (Hilborne etc), then the EFI profiler tends to link the ingition in with the package, so there is a full quota of fuel and ingition optimsation.
When going to AVESCO set-ups, with slide throttle and injector postion far away from the stock EFI set-up, peak power is again imrpoved, and low end claibration becomes very difficult. The engineer then applies more science to the whole power curve to get some kind of driveaility to the pits or 40 km/h drivability in the pits..
When you look at the IDA Weber versions of the same Windsor engines, then they yield class leading power at the peak rpm because they size the carb to the given curve, then optimize. Area under the curve is probably less, power peak is often more. The ignition systems are often separated like in the bad old days of TransAm, so effective engine mapping is 'fuel only, by Weber', not a linked fuel and ignition set-ups like we are seeing.
Once made, a modern EFI system is type cast, and the injectors and inlet runners are fixed. On most DCOE/DHLA/DHRA/IDA set-ups, tuned length , carb position (elevation and runner lenghth) can be easily changed.
On Motorbikes, a similar situation exists, where the EFI set-ups are employed due to modern constraints. Mapping a engine takes an age. In the old flatside Mikuni world, more power is there at the rpm peak.
Anyway, I've not been hard working enough to do what you've done, so my asserations are based on other peoples evidence. I read automotive agony columns, where people relate their calibration problems, and the focus of my attentions are V8's and fours. I've been immersed in doing 5th order polynomial regressions on experimental data, and I believe that an engine is just a pump which can recieve modulation form the EFI system. I think that the EFI system cannot actually create any extra power, even if the EFI system has inlet runners which have no 13 to 30% restriction via venturi, its CV or conventional 3 circuit Weber workalike counterpart will eclipse it.
Any way, the solution set for the function of a function I've listed above has been a 5 year problem for me.
I've used residential mapping to create a lookup table of data sets for road roughness and chemical applicator projects, and have come up with valid selections that are easy to implement by a computer. I'm not anti-Electronic per se, I just don't like putting scala values into some boxes like GM's cal pak set-up, it makes you think your controlling the VE table. You not, your obtimising fuel delivery by pulse width. I've been bitten by that bug twice, and recon that a lot of wrong thinking comes about from just working out which lever gives you a good result, when its better to find out why on a one alteration per test basis.
With electronics, there are serveral ways of getting good results which are actually wrong. For example, Mitsubishis fuzzy logic Magna transmission, and the torque demand optimisation system where ingition and throttle are performance inputs (David Vizard discussed this in 1983 in his Ford SOHC turbo work, on how to degrade spark to control torque rise)
The solution for the above IR Carb "function of a function" is not to integrate dy over dx, but to map a 4000 to 10000 rpm table in 100 rpm steps, and vary the Ln's Y intercept scala co-efficients as a function. I've done that many times in five other major projects. You are then forced to understand how the engine responds to inertial ramming, in a manner like Fords F3 EEC graph. You are creating a 3D Autocad relief map of an engines air supply needs.
Inertial ramming in an Independent runner engine is the reason for the changes in co-efficent. I'll post it when I've mapped it. It is an example of what I like about electronics.
With as much respect as I can muster, I'm certain the realtionship between venturi and rpm and cylinder size is a heck of a lot simpler by eliminating VE.
If I'm wrong, I'll just copy what you do, after I've worked it out, but I'm certain 40 years of engine research brings into relief that an engine is just a pump, and we tune to the air supply, we don't have to think VE all the time. VE is going backwards to go forwards, in my opinion.
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