Radium Fuel Pressure Damper

doublespaces

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I recall @martymil mentioning this has helped in another thread, however has anyone else attempted to install one of these to cushion some of the low pressure spikes?


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martymil

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We have a number of cars running these here, whilst the damper helps it doesn't fully stop the spikes and other mods need to be done to fully smooth out the lpfp.

The spikes are caused be the switching hpfp valve, the lpfp factory system is not good enough to control this when the fuel hpfp pressure is almost double what factory intended.

But it can be controlled but it's not cheap.

Unless the spikes are causing you tuning or code issues I wouldn't worry about them.

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martymil

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This is probably correct. I don't think you would see them with an analog monitor.

Sorry guys but that is incorrect, I actually run an analogue meter and you do see the fluctuations if you have them, as I said originally unless your having code or tune related issues
don't waste your time trying to smooth them out as it can get expensive just to have a pretty log.

A damper is the cheapest solution that will at least halve the oscillations but not fix them completely.

FIY don't run a boost reference line on one of these as the oscillations can get worse if you do.
 
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Blaster3500

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Sorry guys but that is incorrect, I actually run an analogue meter and you do see the fluctuations if you have them, as I said originally unless your having code or tune related issues
don't waste your time trying to smooth them out as it can get expensive just to have a pretty log.

A damper is the cheapest solution that will at least halve the oscillations but not fix them completely.

FIY don't run a boost reference line on one of these as the oscillations can get worse if you do.

Does and aftermarket regulator have more of an impact on the fluctuations compared to the damper?
 

martymil

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they complement/work together nicely with a return line.

Just a hint run the lpfp sensor off the fuel regulator reference port.
 

Blaster3500

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they complement/work together nicely with a return line.

Just a hint run the lpfp sensor off the fuel regulator reference port.

Thank you! I have followed some of the information you have posted in the past regarding the fluctuations.