Fuel Injector Chat and Discussion

[soxfan143]

Originally Posted by Supa Ninja

I have messing around with my fuel maps and IAT cranking compension map. My battery has taken a nose dive with cold wave but I may have gotten it. Next week I'm ordering a Deka and a PWJ battery mount. It's better but I still need keep plugging away at it. I wish I could have a accurate AFR reading while cranking that would make this simple. I'm using the 60 psi latencies but since my 1:1 FPR reduces fuel pressure in vacuum I think is one of the reasons I'm having difficulties. Tomorrow I'm going to put the check valve back on it and see if that makes it better. With the check valve I'll be at 60 psi all the time.

Interesting. You should be able to compensate for the pressure drop in vacuum by adding fuel in the IAT cranking comp tables at that temp. You're the reason why I haven't attempted installing my IDs yet. It's 0 degrees here. Literally. No way I'll be able to get them dialed in in this weather. lol..I'm waiting for Mucter to figure it out...lol...

[Supa Ninja]

Lolololol, I'm waiting for you mucter to figure it out too. I'll be getting a new battery in the next couple of days, then I should be able to figure this out. I need to up my fuel pressure too, the last datalog I did I was at 86% IDC. Probably because of the ambient temps. Aside from the cold cranking issues these inj are the atom bomb.

[soxfan143]

Originally Posted by Supa Ninja

Lolololol, I'm waiting for you mucter to figure it out too. I'll be getting a new battery in the next couple of days, then I should be able to figure this out. I need to up my fuel pressure too, the last datalog I did I was at 86% IDC. Probably because of the ambient temps. Aside from the cold cranking issues these inj are the atom bomb.

Yea. I can't wait to get them in. Although just swapping to the Full-Race mani and stuff made my RC injectors seem to work better. I'm not getting the misfire anymore and the car idles like butter. Before it was popping and cracking at idle and i was getting hesitation at tip in but that has disappeared since unloading that Greddy log(of crap) manifold.

I can just imagine how insanely awesome my car will run with the IDs in there. Hurry up Jay and get me a starting point...Hehe..

[Supa Ninja]

If you want I cam post up what I got so far mike

[soxfan143]

Originally Posted by Supa Ninja

If you want I cam post up what I got so far mike

OK.Thanks. But your pressure is not the same as mine so my latency will be different. I should be running about 65psi but who really knows until I get a fuel pressure gauge on there. lol..

[nycclaye]

hey, did you guys get a tracking number from T1 when you guys ordered? I bought that, and the 4bar MAP sensor the same day and I just got an order confirmation from the map sensor.

[Bugermass]

One thing you guys also have to keep in mind. When the voltage drops, even if your injector offset tables are correct for the injectors, you will still lean out due to the fuel pump not being as effecient. I've seen huge differences in flow of stock and aftermarket pumps just by going from 14 volts to 12 volts and even more so at 10volts. And the worst thing about this phenomenon is that you won't notice it at idle where fuel is at a very light demand, it mainly shows its ugly face when under boost under high fuel demands. Just somthing to keep in mind.

[nycclaye]

well, if ya'll want, i have my tuning appointment set for at the latest, the first week of march, but i'll probably go up and get tuned again by forged performance in atlanta, ga around the 15th of feb or maybe even the end of this week since my tax returns didn't show up last week as scheduled.

i can ask these guys some questions too. i know we all have inside lines, whether it be tuning our own cars, or from Doug at Hondata, but the great thing about tuning is that each person does it differently and is able to create new ideas based on the opinions of others.

both Sharif and Scott of Forged Performance are open to lurking thru our threads, and I've already sent them a few of them to look thru. They do it as needed for me, but do it very often for on lots of forums...

I'm not discrediting anyone, as i've had Mike (soxfan143) be more apart my build process than I think anyone. I take everyone's input, even if Nick (Supa Ninja) picks on me for having a baby turbo compared to his , and sorry Mucter, but your the guinea pig for a lot of us. Thanks for your words, and i hope you keep trying stuff before me. that way if you break something, I know what NOT to do

even though i'm the only one on here to shatter an NST idler pulley right after being tuned though

any questions that I can shoot them?

[mucter]

Sorry guys, had an INSANE weekend. My 91 Integra started leaking coolant from the water pump, so I had to pull everything apart and have a look. Well it turned out the pump was about to esplode. Needless to say I replaced the pump, timing belt, tensioner, replaced the plugs, oil, etc, etc etc.... I kinda went nuts and just did a major tune up on the car. We also wired in a 4-wire o2 and got that up and running with Hondata S300.

I had hoped to have a bunch of info and a tune done on the Si by now. But the honest truth is that as it sits right now, it only has one fuel injector connected. I have to go out and wire up the other 3 still. The pnp clips I was sent from T1R are not pnp, I was sent the wrong clips. Mike sent me a picture of his, and his look correct, so it was just a simple mistake. Not a huge issue and I'm just working around it so I can get the car up and running.

Thanks to the teg, I didn't get to start working on the civic till late last night. Doug @ Hondata sent me his fuel pressure tester and asked me to run a series of tests as I upgraded my fuel system. I am testing the affects on fuel pressure and duty as I go from stock, walbro, ID's and crushed FPR. In that order. I'm doing tests on the fuel pressure at idle and at WOT both at the tank and at the fuel rail (this is fun because it requires a passenger to hold the pressure gauge through the window of the car LOL).

I was able to get tests done last night on the stock fuel pump and then with the walbro installed. I have some interesting data to share with everyone when I finish my tests. I'll be posting a new thread with a bunch of info when I'm done. Hoping to get it all finished up tomorrow night.


Here's a pic of the water pump, ever seen one worse than this? LOL

[Supa Ninja]

Holy crap that water pump looks bad, at least all the maintance is done for now on the teggy.

Jay I'm all excited to see your results from the fuel system testing. Finally we will have some conclusive proof as to what's really going on, instead of all this speculation.

[nycclaye]

what exactly are we looking to see?

The first test was with the stock pump and what injectors?

The second is the walbro and what injectors?

the third is the walbro and the ID1000's...

and the fourth is the walbro, ID1000's, and the crushed FPR...

couldn't we just put in a AEM brand or Comptech Fuel Pressure Regulator to keep things more stable? since most of us are running the walbro, just to keep the voltage, and the pressure up, (remember i'm still learning) I see the aftermarket fuel rail with the Fuel Pressure Regulator being logical.

fyi.. i'm a kid in a candy store right now!! looky what the mailman brought in three days ago and I just picked em up from my rental office!!

[mucter]

I recently decided that I'd had enough of being worried about fuel on my car. I simultaneously went about getting a Walbro 255lph HP pump, CT-e FPR crushing tool and Injector Dynamics 1000cc injectors.

Doug@Hondata noticed I was about to install all of this and stopped me before I did the install. He asked me to run a series of tests to see how each mod increased my fuel pressure and the resultant duty cycle at WOT. He sent me his Honda fuel pressure tester and asked me to test each mod with a 3rd gear pull, monitoring the fuel pressure at the tank outlet and the fuel rail.

I have to give a shout out to my buddy Adam for helping get this done. He had to hold the fuel pressure gauge routed through the window of the car. Trying to hold on and look at the resultant pressure while we're hurtling through the dark rainy Oregon weather...LOL

When I started the test, I had the stock fuel pump, stock un-crushed FPR and RC 550cc injectors. We started by measuring the output of the stock fuel pump. Some of the mods showed a variance in pressure from idle to cruise. Of course since the stock system is returnless, there is a dramatic pressure drop under boost. The resultant psi under boost will be signified by "WOT".

Stock fuel pump, stock FPR, RC 550cc Injectors
Duty Cycle - 100% @ 10.1psi/8000rpm

Fuel Pressure
At tank outlet:
- Idle & cruise: 54.5psi
- WOT: 49psi

At fuel rail:
- Idle & cruise: 52psi
- WOT: 43psi

Walbro 255lph HP Fuel Pump, stock FPR, RC 550cc Injectors
Duty Cycle - 98% @ 10.1psi/8000rpm

Fuel Pressure
At tank outlet:
- Idle: 58psi
- Cruise: 56psi
- WOT: 50psi

At fuel rail:
- Idle & Cruise: 56psi
- WOT: 45.5psi

Walbro 255lph HP Fuel Pump, stock FPR, Injector Dynamics 1000cc injectors
Duty Cycle - 62% @ 10.1psi/8000 rpm

Fuel Pressure
At tank outlet:
- Idle & Cruise: 56psi
- WOT: 51psi

At fuel rail:
- Idle: 56psi
- Cruise: 54psi
- WOT: 44psi

Walbro 255lph HP Fuel Pump, CT-e Crushed FPR, Injector Dynamics 1000cc injectors
Duty Cycle - 53% @ 10.7psi/8000 rpm

Fuel Pressure
At tank outlet:
- Idle & Cruise: 72psi
- WOT: 64psi

At fuel rail:
- Idle & Cruise: 70psi
- WOT: 58psi

[Supa Ninja]

So just the walbro alone added fuel pressure at wot. Looks like a crushed fpr is a good idea but your idle fuel pressure is crazy high. Fuel return ftw!

[BlueSi4]

Do we want the idle pressure to be that high?

58psi at WOT sounds good

[soxfan143]

The ID 1000s like fuel pressure at 90psi. They will idle perfectly at 90psi. The atomization is better at that pressure. No need to worry about pressure that high at idle.

[BlueSi4]

So basically, you want the FPR crushed along with the ID1000 injectors and the Walbro IF you don't have a fuel return line, correct?

[Supa Ninja]

Oriol-that sounds like a solid setup.

[BlueSi4]

With that said and sorry for my noob status as far as fuel injectors and pressures go...the 14psi change between crushing the FPR and not crushing it, what does that deliver when the car is driven? What does it affect?

Is the higher pressure something that helps lower the duty cycle? Is it something that helps the injectors deliver more constant and stable fuel?

[prizm5063]

Mucter, was your AFR consistant between the different runs? Did you do any tuning between each setup to ensure your ran a perfect 11.5(or whatever you choose) between runs?

[mucter]

Sorry it was late when I typed that up, I forgot a few details.

Yes I tuned in-between runs. I had to... each time I added a significant amount of pressure, the car would run pig rich.

The difference in AFR between the stock pump and the walbro was subtle... Not a big gain in overhead.

The ID injectors LOVE high fuel pressure, it's ideal for them. The car ran smoother at part throttle and idle after I crushed the FPR with them installed.

My car is running on the Greddy basemap, with ID's latency values for 70psi. I've done my own re-mapping of the entire fuel curve.