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Fuel pressure fluctuations

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Is it normal for fuel pressure to fluctuate 2 psi like the below pic. Would this be an issue worth looking into deeper? Im using a new Turbo-smart FPR and Walbro 450 pump. Map pressure looks good tho.

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That's within normal range, nothing to worry about.

Mine has 4psi fluctuation through WOT operation when running at 60psi, and we just had a look at the log from the 86 and it gets a 2.9psi variance.

The quicker your sensors react, and the higher the refresh rate of your sensors the more you notice these things.

Depending on what is causing it, it's possible that a fuel pulsation dampener might help.

But I suspect what you're seeing is just the fluctuation of the FPR needing to react to a different volume of fuel passing through it as the injector demand increases. As it is a mechanical device that doesnt work instantly. Remember that if you are logging at 100hz, the reaction time of the FPR that you're noticing is still maybe only 1/20th of a second or something like that.

Thanks David that makes me feel better. I have a Marren pulse damper and the the pressure trend is the same with and without it installed on the fuel rail.

At least the differential pressure is consistent and not dropping off.