My fuel curve is kinda screwed up right now. It runs rich till about 4K when full boost is there.... then from 4K to vtec it runs lean.... sigh... then in VTEC and full boost it runs rich. I have a vortech FMU, a bosch fuel pump, a J&S safeguard with dual monitor, and a SFC-VTEC.
Besides using the SFC to rich out the midrange what other options do I have to get it to give me more fuel in just that area? I'm thinking either an adjustable fuel regulator or one of those programmable extra injector systems (does anyone use one of those?!).
A standalone is out of the question right now (broke UCLA student).....
My J&S is set to min sensitivity....
Dirtylude: I read your instructions on installation (Thanks man, you saved me a lot of trouble! =)) but as soon as its set at anything but minimum sensitivity it pulls ignition like crazy with just normal driving....
Oh yeah, I'm using the stock knock sensor and not the one included with the safeguard....
thanks a lot guys, i think i already asked questions about my fuel curve problems but i'm hoping somebody can help me out! Thanks to Pure Lude and Dirtylude for your help before!!!!
AGGHHH!!!! All the extra money a college student can put into a lude and still not running good!!!!
Originally posted by preludeboy My fuel curve is kinda screwed up right now. It runs rich till about 4K when full boost is there.... then from 4K to vtec it runs lean.... sigh... then in VTEC and full boost it runs rich. I have a vortech FMU, a bosch fuel pump, a J&S safeguard with dual monitor, and a SFC-VTEC.
Besides using the SFC to rich out the midrange what other options do I have to get it to give me more fuel in just that area? I'm thinking either an adjustable fuel regulator or one of those programmable extra injector systems (does anyone use one of those?!).
A standalone is out of the question right now (broke UCLA student).....
My J&S is set to min sensitivity....
Dirtylude: I read your instructions on installation (Thanks man, you saved me a lot of trouble! =)) but as soon as its set at anything but minimum sensitivity it pulls ignition like crazy with just normal driving....
Oh yeah, I'm using the stock knock sensor and not the one included with the safeguard....
thanks a lot guys, i think i already asked questions about my fuel curve problems but i'm hoping somebody can help me out! Thanks to Pure Lude and Dirtylude for your help before!!!!
AGGHHH!!!! All the extra money a college student can put into a lude and still not running good!!!!
when i had my ultra j&s it started to pull out a lot of timing as well. I never really figured it out, so i sold it off when i got the hondata system.
I don't know how to fix your fuel. I've never tried tuning an FMU system before.
My J&S with the stock sensor was very near min when I had the turbo on. What seems to happen to me is that when a little detonation occurs on tip in, it just doesn't want to settle down that easily. I thought it was just noise from the turbo, but when I took out the turbo and played with it using the Haltech, changing the fuel values, and swapping the stock ECU back in once in a while. Using the stock ECU, even set 1/4 away from max I can't get it to go off. With the Haltech slightly untuned I could get it to go off just like when the turbo was on. There's definitely a little detonation occuring with the turbo, I think it just takes it too far trying to correct it. It was definitely very helpful when street tuning using the stock O2 sensor, and when I took my engine apart the pistons where near perfect. Makes me wish I'd turned up the boost higher.
I'm not certain how bad it's going to be with the JE pistons rattling around in there. I'll find out soon.
__________________ DirtyLude
Mark Higgins
Toronto Prelude Club www.hondaprelude.to
What is your full boost (PSI)? With anything less than a 10:1 FMU disc, the midrange will suffer. Just the fmu with a 12:1 disc and turbo kit should be good to 8-9psi. With the sfc, you'll want to lean things out, not richen....ecu goes crazy. Since you have the bosch, use a 10:1 or 12:1 disc (if that is what you currently have, you may have other problems). A good investment for you would be bigger injectors. I found some 450 DSM injectors for about $100. With the injectors, you could run a max of 60-70psi under boost....... It does take a bit of modifications for the dsm injectors, but they're cheap.....
hey thanks a lot for your help guys.... yeah i think I'm just going to up the boost and just drive the car for the high end.... every other solution just seems a little too expensive for a couple weeks..
its good to hear about the J&S settings with your cars cause i thought my unit just sucked! =P
well i won't think its a piece of junk if it saves my motor =)
00G... i'm going to try 7 psi first and see how that works out
No matter what I set the sensitivity to, it would pull 8-10 degrees of timing on top of what I was already retarding manually. The map limiter on mine didn't work all the time, the voltage would spike and freak out my ecu. Above 5k rpms, the stock ecu doesn't listen to the knock sensor outputs because they are inaccurate (engine noise mostly), the J&S does react to the false knock sensor outputs at high rpms. Garbage in = garbage out.
I am better off now with near stock timing and a check valve.
It costs $700 with the gauge, you can nearly buy a standalone for that much.
man are those problems confirmed? damn..... anyone else with a J&S have these problems? All i know is that set on anything but min sensitivity the J&S pulls like crazy
Turning off the knock sensing above 5k is more an indication that the stock ECU wasn't up to handling the processing needed at that speed, not that it can't be done.
I ran the J&S for 6 months before I got the turbo. With the sensitivity set to almost max I never got a flicker out of it, track racing and just hard driving while redlining the car. With the turbo on I would only get it when I hit the gas. I would have to accelerate very slowly not to set the damn thing off.
The J&S V.0 (the one without all the added crap, like boost retard and the map limiter) is $429.00. If you have a fully tuned standalone, the need for the J&S is just not that great on a street car. You should have tuned all knock out properly using a safe map. The only use it would have is if you are using a race tune that is vey close to the edge or if something goes wrong, like a leaky fuel line.
I'll definitely be keeping mine, since I'll be running several different maps.
__________________ DirtyLude
Mark Higgins
Toronto Prelude Club www.hondaprelude.to
Originally posted by DirtyLude Turning off the knock sensing above 5k is more an indication that the stock ECU wasn't up to handling the processing needed at that speed, not that it can't be done.
No, I will have to disagree with you there.
This is a quote from Hondata.
"The knock sensor does not help for what most people want - preventing or detecting detonation with forced induction. The stock knock sensor does not function after 5000 rpm because it cannot distingush between general engine sound and knock. Also it just looks at the signal level from the knock sensor, so anything you do to the engine which makes it noisier (like forged psitons) will fool it. However, human ears are fairly good and by feeding the knock sensor signal into an audio filter and amplifier, you can distinctly hear detonation at any rpm. HKS makes a similar device which uses its own microphone, but I like using the stock knock sensor."
It doesn't say anything about the lack of processing power of the stock ecu. It states plainly that the knock sensor cannot correctly distinguish knock from general engine noise at high engine speeds.
__________________
Last edited by inlinefour : 10-24-2001 at 09:55 AM.
It does not say why it cannot detect knock above 5000 rpm you are reading into it that it is somehow impossible to do so. It is refering to the stock knock sensor and not all knock sensors. This is another quote from their site:
Quote:
The stock knock sensor is designed to compensate for different qualities of fuel, and has a limited scope of adjustment. It is not designed to compensate for detonation under boost and may be fooled by forged pistons rattling, into retarding the ignition when knock is not present.
Obviously they recognize the limitations of the stock knock sensor. It is not even close to the sophistication of the J&S. The idea that the human ear using a speaker attached to the sensor can detect knock that an electronic device made specificly for that task cannot is absurd. The J&S listens to the specific frequency that knock causes the block to ring, and also only listens at the specific time in the engine cycle that it will occur (the compression stroke for all 4 cylinders).
You yourself may have had a problem with it. You're the only one I know of who tried it on an H23, and the H23 is known for it's very loud valvetrain. Many people have been using this with JRSC boosted B series engines with no problem. So far you are the only one I have heard of who has had problems using it at any sensitivity with a stock bottom end.
The only problems I've heard that fake out the J&S is VTEC cross over, which has supposedly been solved on the new versions, and the loose forged piston issue. I'll see on my own in about two weeks about the forged pistons on my own car.
__________________ DirtyLude
Mark Higgins
Toronto Prelude Club www.hondaprelude.to
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