Quote:
Originally Posted by NC427
Fred,
Thank you so much!!!!!!!!
The information you provided is helpful to me in any respect - So I will very likely follow your suggestion and start training myself prior to making any final decision.
I guess this really will make sense as we do have a variety of so called "experts" on this side of the pond in regard to tuning aspects for FI systems but frankly I cannot judge their real life abilities and I have heard some stories which have not really been encouraging as well as others which sound quite promising.
Myself I would rather prefer being able to make a well founded decision instead of "betting" on choosing the right expert. This is also why your input is appreciated so much - you went through the process already......
As my heart is still torn appart between a real life (almost) self tuning system like the mass flo (which has no traction control feature) and a stack system which will force me to really get involved into the mystery of FI I will follow your recommendation and try to get started from the right end: "Tune" my own abilities and make my choice once I feel that my own knowledge base has grown.
Fred, alongside to your general helping attitude I guess the thread and evolutionary discription about ERA 753īs development is outstandingly helpful in many respects and to many people / especially once it comes down to non-standardized solutions for certain obstacles we are all running into from time to time. I persume I am not the only one having read the thread mmore than once.
Thanks again
Carsten
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Hi Carsten,
Thanks for the kind words. I think that the more folks like you who learn EFI systems and use them on their cars, the better for our hobby in general.
Just a couple of additional thoughts to help you think through the choice of a "self tuning" system like MassFlo vs. more advanced systems like FAST etc. While I have not worked with a self tuning system I suspect they do work well on relatively mild engine combinations that don't have alot of tuning issues to begin with. For a system to "learn" the proper tune, you need an engine that does not have an issues like reversion problems, or other difficult to tuning characterisitics. They systems also have somewhat limited performance capabilites due the the Mass Air Sensor approach they use which is arguably the easiest to use fuel management strategy (most EFI system like FAST, etc. offer multiple engine management strategies which usually include a minimum of Mass Airflow, Speed Density, and Alpha-N fuel management strategies). If you are working a maximum performance application (say 500 hp or more or if you are using nitros, turbos, or a supercharger) you will probably not be able to get the best results with a self-tuning system. The other reason to spend the time learning to tune a more advanced system is that its fun! Once you get the hang of it, you can make your car do what you want it to do pretty predicablely and you will also have the satisifcation that you optimized your car's performance in the way you see fit. I personally think its pretty cool to be able to change my engine's characteristics with a laptop and some time spent testing and making adjustments.
BTW, here's a little more on the three most common fuel management strategies:
+ Mass Airflow - a sensor is used on the intake side at or ahead of the throttle body that estimates the mass of the air flowing into the engine. This approach is very accurate because the mass of the air one of the most basic variables that determines how much fuel an engine needs. The drawback to this approach is that measuring air mass usually involves a sensor that can have somewhat resticted airflow. These sensors also aren't practical with multiple throttle body systems like stack injectors, hat injectors, etc.
+ Speed Denisty - this is probably the most common strategy in street max performance and many racing applications. The Vacumn or pressure in the intake manifold plus the air temperature are used together to acurately estimate the mass of the air going into the engine. This approach has the advantage that it does not restrict the inlet of the throttle bodies and it works extemely well with turbos and superchargers because in can accurately measure boost pressures and inlet temps under boost which allows for some special tuning techniques in these very high performance applications (ex. you can add more fuel under high boost to manage detonation and control combustion temperatures so you don't melt pistons, overheat exhaust valves, etc under this high stress situations). Speed density can be used with stack injection systems if the manifold has the necessary plumbing to create a common plennum between the runners where the manifold pressure can be measured. I am using Speed-Density on both by superchanged motor and the stack injected FE in my cobra.
+ Alpha-N - This a more tunable, computerized version of the system that mechanical fuel injection systems have used for years. The angle of the throttle blade(s) and the engine RPM are used to determine how much fuel the engine needs. This method is often used in race applications where the camshaft selection is such that the motor his little or unsteady manifold vacumn at idle and low RPM. This approach works OK in a race application where part throttle and low-RPM drivability are not the primary concerns but usually results in less than an ideal tune for a street drive vehicle. The usual end result of this strategy is an engine that runs more rich than is ideal in some ranges of the car's operation.
Glad you are find this information useful and I am happy to answer you questions to help you and also hopefully help others on the forum.
- Fred