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Discussion Starter · #1 ·
The Mach Z engine management system monitors intake air pressure, intake air temperature, engine RPM, throttle position and engine coolant temperature. For a given set of the above parameters, the ECU sends a predetermined amount of fuel to the engine. After installing your cylinder domes, the ECU will still send the same amount of fuel to the engine for these same parameters. So here are my questions.

Is the increased horsepower coming from improved combustion efficiency?

Is the compression ratio increased?

Can the same horsepower increase be achieved by leaning out the fuel charge therefore improving combustion efficiency?

Note: I have seen a 7 or 8 horsepower increase (Dynotech Research data) on a stock Mach Z by just leaning out the fuel charge.

Can an even greater horsepower increase be obtained with your domes if the fuel charge can be increased?
 

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Discussion Starter · #2 ·
One more question is it harder (as in pull) to start with the new head?

The heads really look great!
 

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Discussion Starter · #3 ·
I guess no one has a response to these questions. There are more questions that should be asked.

Does the exhaust gas temperature change? + or -

If BRP does a remap, will the modified head still work? I guess you won't know depending whether they lean or enrich the existing mixture. Or maybe change the ignition curve.

Can your heads be run if the decompression plug has been eliminated?

Can your heads be run if timing is advanced?

I will understand if you don't answer these questions on the internet, since somebody always jumps down your throat. Feel free to PM me if that is the case or maybe you are just too busy which I can also understand.

Don't get me wrong. I believe all of your claims for your products and think they are all top quality. If it wasn't for businesses like yours, we would all be driving stock Mach Zs or even worse doing our own trial and ERROR.
 

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I think these inserts are all similar to an RKT head-hemi chamber that is supposed to burn more efficiently. Hemi dome is supposed to make more power with less fuel-and you can lean it out more with less chance of detonation. I believe Cudney's head raises compression .85 over stock-that is where the power increase is coming from-he can get away with the increase because of less detonation because of the chamber design. I would think they will work with re-map and everything else-knock sensor will do what it does now. Timing advance, decomp plugs, etc should all be ok with the change in heads-computer will do the rest.
 
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