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Measuring air flow

EFI Tuning Fundamentals

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Ok so here's my dilemma. Brand new to tuning and calibrating and I need a little bit of help understanding a few things. I've got the general idea and I know I'm just missing a piece of information. I've got access to both a chassis and engine dyno at my job thankfully. So I have a 347 Ford stroker that I am working with on the chassis dyno and an aftermarket Holley Sniper EFI system. I am fairly familiar with the software layout already. So here is where I am at. Working on a spreadsheet for my engine math and my volumetric efficiency. I will include a screenshot of what I am working with there in a moment. Basically I'm trying to get my VE calculations done so I can populate everything a little bit quicker. I've calculated the airflow, the mass airflow, I've calculated for air density using an assumed pressure of 14.7 and 60 degrees farenheit or 519 on the rankine scale, I've got the area of bore figured, the volume of the cylinder figured, and I just need a way to get the VE.

So long story short I guess I could have asked what air flow meters are available aftermarket or what are you guys using? Will be doing a lot of carbureted cars/efi retrofits, aftermarket efi installs, and some factory car tuning. Any help would be greatly appreciated.

Here is my chart that I've kind of been working off of. If you guys have any questions to how I arrived at anything let me know. I've got my equations and math with me

Attached Files

So you have table with what the airflow would be at 100% VE. The missing piece of information is what your actual VE is at all the operating conditions. You can probably fill the entire table with 60% , get the engine started and running on the dyno, then start to dial in the shape of the curve. We use the wideband output to help us figure the Volumetric Efficiency. Set a target Lambda of 1.0, and adjust the cells while the dyno is holding the engine in that condition. I'm pretty sure the worked examples in the standalone courses show this process. The Holley may have a default map that could be an even better starting point, or a map from a similar engine.