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    Producing Quality Computer Tools for Racers and Engine Builders since 1986






Head Flow

What is Head Flow?


Flow Curves
Flow Curves
Head Flow is the efficiency at which the air/fuel mixture flow through the ports of the heads. Back in the 60's and even as recently as the 80's, car manufacturers where making very inefficient heads. They had small valves and very poor efficiency. Around 35%. Now car manufacturers are getting efficiency ratings in the low to mid 40's. And some aftermarket head manufacturers are getting efficiencies close to 50%. These my not seem to be a big increase but think of it this way. back in the 80's the Ford Mustang 5 liter V8 engine was making about 225 horse power. Now the 2011 Ford Mustang with the same displacement is rated at 400 horse power. And even more impressive the 2011 Ford Mustang 3.5 liter V6 is rated at 305 horse power. And they are doing this mostly with improved cylinder head efficiency.

Another example would be the Mopar 318 vs. the 340. The 318 was always considered to be somewhat of a dud. But the 340 was considered a great motor. Why? Because of the heads. If you where to put aftermarket heads on the 318 engine it would perform better than the stock 340 (depending on the heads that where chosen).

Programs and tools that can help you find your Head Flow and Flow Efficiency.

Our Port Flow Analyzer v3.5 program can be used to figure out the efficiency of your existing heads and can also be used to see improvements (or losses) in modifications to your heads.

Plus we have 3 tools that can be added to your Performance Trends EZ Flow System, or other flow benches. Starting with our Automatic Valve Opener. Allowing you to make 50 different lifts automatically. Plus our Swirl Meter allows you to measure intake mixture motion on your flow bench. And finally our Tumble Adapter makes it possible to mount our Swirl Meter sideways so you can use it to measure Tumble.

We have 3 programs that work with Head Flow data inside the the engine when conducting Engine SimulationEngine Analyzer v3.4 Standard allow you to calculate a Flow Efficiency from Flow Bench Data from up to 3 data points. Engine Analyzer Plus v3.4 builds on the Standards version by allowing you to specify up to 8 valve lifts. And Engine Analyzer Pro v3.9 also builds on the Standards version by allowing you to input up to 12 valve lifts.