Rail Pressure Gauge

[hotram03]

Who makes, If anyone, a accurate mechanical or digital rail pressure gauge? Part # and manufactorer please.

 

[Summit]

the outlook monitor from bully dog has digital rail pressure (i use it all the time) and i read somewhere else of another company has digital rail pressure in there monitor as well.

there are analog ones, if you do a search you might find out who makes e'm & who's using them.

 

[raychem]

The gauge is made by SPA and Matt400 did the reaserch to get it working. It uses the factory pressure sender. Serch for matt400 under his posts in 3rd gen forums and you will find it.





Richard

 

[JRG]

I was thinking about this today. A "REAL" guage in place of the relief valve is what I was thinking.



JRG

 

[raychem]

The relief valve is there to bleed off excess pressure unless you are running a mod cp3, I know someone else is working on another gauge but if I remember correctly, it will also run off the stock pressure sender. As for a "real" gauge... I do not know what would br more real than that since I do not think a mechanical means to isolate pressure at that range is viable, I know its possible but will someone realease one since there is little demand for it.





Richard

 

[RMalone]

I have the SPA, wired to the stock sender. Can't say I have heard of a guage that measures rail pressure directly, via its own sender. Obviously you cant have a guage in the dash directly measuring 20,000+psi, so some type of sending unit is mandatory.

 

[JCleary]

I was thinking about this today. A "REAL" guage in place of the relief valve is what I was thinking.



JRG

You can measure the pressure with a transducer, but they're extremely expensive. They'll measure to over 30,000psi, but I think they cost well over $1000. I have a PM somewhere that specifies the type of transducer one popular vendor is using to tune his pressure boxes. I can dig it up if necessary.



I have a SPA gauge and they are still available from SPA.



DLeno on this site is also working on a DiPricol Optix analog rail pressure gauge, it's supposed to be ready soon. I've been putting off installation of my SPA as I'd rather have the DLeno gauge.

 

[jokerzwild]

SP Diesel has a rail pressure gauge built into there new boxs have 1 on my wifes Jeep liberty diesel an my buddy has 1 on his 06 Dodge both work great thinking about getting 1 for my truck.

 

[hotram03]

thanks for the replys,I believe I will wait for dleno's gauge as well... .

 

[DLeno]

Here is a description of what I'm working on. -Doug

 

[Luken]

I can't wait Oo.

 

[JohnCooper]

Who makes, If anyone, a accurate mechanical or digital rail pressure gauge? Part # and manufactorer please.

I believe the new "Commander" engine monitor from Quadzilla will do this. Says that it monitors (and displays) injection pressure, I'm assuming this is rail pressure.



http://www.quadzillapower.com/commander/index.html

 

[DLeno]

There are other digital options as well. I've just found that watching the real behavior of the rail is just best accomplishe with an analog gauge. I have eight SPA channels going in my truck, so I'm a real digital guy in most respects. But for this one I gotta have analog.



One of the important goals I had in this project is to produce an independant gauge, separate from anyones' pressure box, that can be independantly plugged into the rail pressure sensor and stacked with anything else.

 

[jokerzwild]

Not trying to get off subject but what should I be seeing in rail pressure with no boxs or programmers fooling things just injectors? It idles now around 4000-5000 makes 11000-12000 cruising at 70mph and will flash up to 26000 then fall off an hold about 17000-18000 at wide open on a hard run. I took line off to check pressure relief valve an had very little fuel come out at idle.

 

[DLeno]

the answer depends on how you are measuring it. to obtain those numbers, are you using DRB III or an after market digital guage?

 

[jokerzwild]

Using a digital gauge built on the SP diesel box going to check it with a scanner tonight.

 

[DLeno]

I think what you may be seeing is a digital spike. average rail pressure never reaches 26,000 in that rail without pressure fooling. What I have noticed is that when I measured rail pressure with a fast digital gauge, I saw some very high spikes that approached the electrical limit of the factory sensor. This can occur especially if you are running heavy fueling (like injectors). when you suddenly back off, the CP3 can't react quick enough so rail pressure spikes up momentarily.



your average numbers sound right to me. if you are seeing a hard flash up to 26,000 under constant load (not backing off the throttle) then you are probably seeing an artifact of the digital circuitry interpreting the analog signal from the factory sensor. What you need to know, in order to intepret this result, is the averaging behavior of the digital gauge; how fast it reacts. there's a lot of noise on that line and a fast, sensitive gauge can lie.



your injectors could be influencing the rail; I just can't say without knowing more about the averaging behavior of the digital gauge. now you see why I like the analog so much it can follow a quick surge in the rail but it won't follow a digital spike. and what you watch is the true averaged analog behavior of the factory sensor



Doug

 

[JRG]

High Pressure ???

What I have noticed is that when I measured rail pressure with a fast digital gauge, I saw some very high spikes that approached the electrical limit of the factory sensor. This can occur especially if you are running heavy fueling (like injectors). when you suddenly back off, the CP3 can't react quick enough so rail pressure spikes up momentarily.



Doug

Doug, are you saying that one could see high rail pressures with just injectors?



High enough that when there is a sudden lift of the foot it could cause enough pressure to pop a relief valve?



JRG

 

[JStieger]

I maxed out my SPA gauge with just injectors and TST. The high number recall was 27,000 psi. I don't remember if this was at WOT momentarily or if it occurred when I lifted off the throttle quickly.



Before the TST, I popped my relief valve late last summer when I was running the 03 Edge Juice (timing/duration/pressure) with injectors.

 

[jokerzwild]

Thanks for the info DLeno I did some playing tonight with the drbIII an found that it is within 1000 psi of gauge usually on the high side. I think your right about the gauge not reacting as quickly I did not see those spikes on scanner making a pass it would hold about 18000-19000 an jump to about 22000 between shifts an came down to 16000 on a long run in 6th gear. This is with box plugged in but on 0 an injectors no programmer. Checked pressure at cp3 pump holds 14psi at idle an drops to 9 on a pass. With the programmer on 70hp tow or the box on anthing over level 5 the pressure wouldnt get above 16000psi anything over lvel 5 an box foooled drb an gauge on box would barely hold 15000 at best. Does this sound like my pumps going bad or is a little over 100hp all a stock pump can supply?