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portlandareae28

Relationship between fuel pressure and boost

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Is there a relationship between fuel pressure and boost?  My truck idles at 17psi, but will dip to 8-9 on a hard run.  Is this having an effect on boost numbers?  I only seem to get to 15-18 stock and even with the edge on (comp not currently tapped) pretty rare that it touches 20psi.  Boost elbow or plugged manifold don,t seem to change anything.

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I’m a round about way, sure. 

 

Realistically its just because the electric pump. Once it’s at full voltage and pressure, it’s constantly trying to provide that pressure. Once the demand for more fuel goes up (ie WOT ie higher boost) fuel will drag a little as its still trying to keep up with the demand. The bigger pumps deal with that better, and bigger pumps with bigger lines do even better. One of the many pros to the mechanical pump is pressure increases with rpm and avoids the pressure drop.

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Posted (edited)

I have been reading up on mechanical pumps, what is the synopsis here on them?  I dig the philosophy, but of course real life and philosophy differ.

 

i am going to do a fuel system sooner than later, trying to decide which route.  Likely won’t go more than a 75hp injector and a small turbo.

Edited by portlandareae28
Added info

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If pressure loss at any point, worrying about an electric system failing or not wanting anything more then the stock fuel filter are on your list then a mechanical is probably the way to go for you. If not then FASS and AIRDOG would be on the table along with GDP’s mechanical pump and take your pick.

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Actually, the truth is BlueChip states on his website you can produce all the HP you want with a mere 5 PSI of fuel pressure. Now, this points out that the VP44 power performance will not degrade with lack of fuel pressure. Now I tell you that you are shortening the lifespan of the VP44 pump if the fuel pressure dips below 14 PSI. At this point, the overflow valve closes and there is no return flow of fuel to the tank. Now you based strictly on the consumption flow for cooling and lubing. The most I've recorded for consumed fuel rate is about 25 to 27 GPH burned on a WOT stand. 

 

 

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Realistically the vp will continue to produce power as long as it has positive inlet pressure. The internal vane pumps kicks arse. Now that being said I would not want inlet pressure that low as everything else will suffer that relies on the fuel for cooling.

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17 minutes ago, portlandareae28 said:

So I just need to decide which fuel system it appears.  I am torn between mechanical and electric...  

I'd probably go mechanical next go around, just not sure on pump hanging on bottom of oil pan, guess no different then filters hanging on side. Although I did get mine up high enough so you can't see them when you bend over ha ha.

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4 minutes ago, Dieselfuture said:

I'd probably go mechanical next go around, just not sure on pump hanging on bottom of oil pan, guess no different then filters hanging on side. Although I did get mine up high enough so you can't see them when you bend over ha ha.

 

Totally guarded by the skid plate.

Image result for mopar1973man airdog

 

Now the first trip offroad to get firewood and skid logs I would end up taking that AirDog right off the frame... Bad idea... No even protected from flying drbirs from the front tires. 

Image result for mopar1973man airdog

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