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Ctsc fuel pressure

Joined
15 February 2015
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Location
Coral ridge, Ft. Lauderdale
I'll be installing gauges this weekend on my 6 psi ctsc anyone here know what the usual fuel pressure should be in boost? I hope it is not over 100psi cause that's as high as my guage goes.
Thanks.
 
I can't tell if you are serious sometimes :). Yes, 0-100 PSI will be fine as far as the gauge goes. If you're exceeding 100 psi fuel pressure then you might as well be flying to the moon.
 
Sometimes I fly to the moon depending on how rough my day was and how much booze I drank. But no, in honesty I don't know what fuel pressure the ctsc should run normally.:wink:
 
With the RRFPR, the pressure can exceed 100 psi in my experience. And that is one big reason I prefer using a piggyback and larger injectors.
 
That is why I posted. I have read here that it is over 100 psi but then I have read that it is under 100 psi.
 
When I'm at my computer tomorrow I can probably find a log of fuel pressure to show you.

Edit: here is is. This is after I replaced my dying OEM fuel pump with a Deatschwerks DW200. It has (to my understanding) a 100 psi relief valve, so one wouldn't expect the pressure to go much above that. In the second log set (fuel pressure is labeled "User 2"), you can see the pressure fall off a bit after peaking, perhaps as a result of that valve.
2014-10-17_newPump.jpg

2014-11-02.jpg
 
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When I'm at my computer tomorrow I can probably find a log of fuel pressure to show you.

Edit: here is is. This is after I replaced my dying OEM fuel pump with a Deatschwerks DW200. It has (to my understanding) a 100 psi relief valve, so one wouldn't expect the pressure to go much above that. In the second log set (fuel pressure is labeled "User 2"), you can see the pressure fall off a bit after peaking, perhaps as a result of that valve.
View attachment 122634

View attachment 122638

Crap. So according to your engine management charts, I need a fuel pressure gauge with a 110 psi max or so.
 
All you need is proper data logger. All those gauges are useless unless you know a midget who's willing to sit in the engine bay and watch that needle dance.

If my memory serves me well on NA we should see 45-50psi peak. Didn't know supercharged at 6psi drinks twice as much fuel. What injectors do you have [MENTION=31260]Jinks[/MENTION]?
 
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Yes the OEM regulator is 1:1, so pressure is ~40 psi at idle and ~50 psi at WOT. The FMU/RRFPR used with the CTSC base kit changes that ratio so that you get the pressures in my curves above. Thus the OEM injectors can supply (kind of) enough fuel. With a piggyback/standalone controller, we go back to the 1:1 ratio and use bigger injectors. Fuel pump is happier and the tune determines fuel under various conditions (load and engine speed, generally).

And I obviously very much agree with solidol that you should have a logger with gauges, not just gauges. The Zeitronix is awesome.
 
@solidol just running the Oem injectors. All Oem fueling system with the standard ct fmu.
Also, my fuel pressure gauge is an in cabin one.
 
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found a log from a few years ago :)

View attachment 122696

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Check out that IAT! :(

It was 65F outside...

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AFR, Boost, Fuel Pressure, RPM, IAT, TPS, BTW :) :)

Thanks Ryu and jwmelvin, it appears that a ctsc runs about 103-106 psi under full boost/ rich setting. That is what I was assuming. I guess my 100 psi gauge will give me a pretty close idea if the fuel pump starts to fail. At one point I almost said, shoot let Shad set it and forget it because as most people state, it is very hard to monitor such things when being thrown back in a seat being forced to drive. But I just wanted mostly to monitor boost to determine a loose belt so I added the fuel pressure gauge as afr on a fmu obd1 car is just inaccurate. Besides I couldn't get over drilling a huge hole to weld a bung on my headers for a uego gauge. I think my gauge hopefully will provide a caution of a possible issue at 100 psi peg.
 
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I have my gauges installed and it appears that my fuel pressure peaks under full boost at 84 psi. But that might also be because the gauge only goes to 100 psi I think, not sure. What's weird is, in first and second gear my boost peak is 6psi. In third gear or higher it peaks at 7 psi.
 
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Seems quite low. The problem with a simple gauge instead of a data logger is that you can't determine if the fuel pressure follows MAP to a point. It's theoretically possible that the FPR is the issue but I would suspect the fuel pump.

Also, I can't see that a gauge maxing at 100 psi would be a problem. It should measure up to that point accurately.
 
The motor runs strong. So I guess I will just take the 84 psi as a point to look at as the normal operating pressure.
I'm liking the stepper motor gauges.
 
No. I only want to measure fuel pressure and boost. Being that I want to keep my Oem cats and not drill into my headers.
I researched afr gauges for months and for what I am running on all stock with ctsc I felt a fuel pressure gauge in cabin was far more simple then a afr gauge being the car is a obd1 with narrow band 02 sensors. The only reason I chose to run a fuel gauge is to monitor my Oem fuel pump only if there is ever an issue. I trust Honda Oem quality and I believe, that if the pump handled the boost in voltage on the dyno, it will handle it on the regular. Some may say that is a risky thing to do but I trust a Honda brand far more then any others. It is very unlikely I will go to high boost anytime soon. The car feels absolutely perfect for the street and requires very little maintenance from what I gather. For now that's the way I would like to keep it. Another 50 hp doesn't seem worth it to me for the risk of a blown motor.
I also messed up my last post. It appears my fuel gauge pegs at 85 not 100 psi. But I guess in theory it will still give me a general idea if the rising rate fpr is working under boost. That is my only concern.
 
Seems like if you are going to rely on fuel pressure as your indicator, you'd want to be able to measure it accurately.

My engine felt perfect until the car was being loaded on a flatbed. Good luck.
 
Thanks for all of your advice. I'm gonna stick with a fuel pressure gauge though as that is really all you have on a stock ctsc, higher fuel pressure under boost. If I went with a afr gauge, I'd have no idea what is optimal and what is not, not to mention, a warm up period for the sensor. If I had bought a used ctsc I might not have been so careless of afr.
 
Not joking.
For example, the ctsc afr can and does move around a lot when on the stock rising rate fpr.
My only statement was, for a guy like me, I have no idea what is deemed optimal afr unless reading it here or having a
gauge that shows rich/optimal/lean and those guages are usually narrowband and worthless. So, call me crazy here, but I trust Shad and ct engineering with the low boost kit. My fuel gauge is to just monitor the Oem fuel pump. The only time the fuel pump gets squeezed into submission is when under boost. At that time, I'm far to busy focusing to look down.
I guess I just have not made it to a stage where I feel a monitoring system is necessary but at some point it may for me.
But either way, I enjoy hearing all sides of the story here. Any knowledge is good knowledge.
 
I agree about looking down although some real-time display is helpful. Logging is key, IMHO, so long as you look at the logs from time to time.

Safe AFR seems to depend on a few factors but I think the idea is that if you see 13:1 under boost, you have a serious issue. 12.5:1 is pretty much the same if you're under significant boost, where target is under 12.
 
I agree about looking down although some real-time display is helpful. Logging is key, IMHO, so long as you look at the logs from time to time.

Safe AFR seems to depend on a few factors but I think the idea is that if you see 13:1 under boost, you have a serious issue. 12.5:1 is pretty much the same if you're under significant boost, where target is under 12.[/QUOT

Here is my afr from the tuning of installation. Looks like it moves around quite a bit with the rrfpr.View attachment 122887Also, I have no idea what I am looking at.
 
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My understanding is that it is undesirable for the AFR to rise above 6500 rpm as yours do. I can find one of my prior logs when I'm back at a computer. It is your duty to learn about AFR now that you have a boosted engine. The shape of your curve is what led me to an FIC and larger injectors. I know you don't like hearing that. And others have good longevity with your setup. I did not, so I made a change.
 
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