Eesh, this is bad.
#1
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Went to the dyno today and these are the results. I know this is bad, but I'm not quite sure why it is so bad and why I'm running so lean between 4k and 5k.
Here's my setup.
Greddy kit at 5psi using the Greddy AFPR with the stock disc.
Tony downpipe
Hi-flow cat and exhaust
1.8 injectors
190HP fuel pump
Olderguy O2 Clamp
Bipes timing controller.
So, yeah it's a band-aid setup, but I didn't think the fueling would be this far off. It seems like the Greddy AFPR isn't really adding enough (any?) fuel in when it gets into boost (which is obviously right around 3500rpm where it starts climbing into lean territory).
I took a pic of the engine compartment because I'm afraid I somehow hooked up the AFPR wrong.
http://www.ihatethissite.com/images/...reddysetup.jpg
Not sure what I should do to fix this.
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***** fucked up.
You could start by ditching that horrible excuse for an FMU and try to find a deal on a used BEGi FMU. I wouldnt be surprised if that fixes the problem.
But in all seriousness, Its time to squirt.
You could start by ditching that horrible excuse for an FMU and try to find a deal on a used BEGi FMU. I wouldnt be surprised if that fixes the problem.
But in all seriousness, Its time to squirt.
#3
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I have a BEGI afpr that I could hook up that I got from a friend. I just need the bracket to hang it in the car. I might as well do it since the Greddy does not seem to be doing anything.
I've also been thinking about Megasquirt.
I just ordered an LC-1 so I can actually tell what is going on with fueling.
I've also been thinking about Megasquirt.
I just ordered an LC-1 so I can actually tell what is going on with fueling.
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The BEGi unit is muuuuuchbetter, since it has adjustable onset and ratio.
When these pulls were made, did you note how the turbo was spooling?
Im thinking that the Vortec FMU, since it doenst have an ajustabvle onset, isnt enriching fuel until you build quite a bit of boost (cuz it sucks), so when it starts spooling at 3500 rpm, it goes lean, and then finally up at 5k when youre into some real boost, he FMU decides its time to add fuel.
If the BEGi unti is workinf right you should be able to tune it out muuuuch better. So at least the car will be safe.
Then get to work on the megasquirt
When these pulls were made, did you note how the turbo was spooling?
Im thinking that the Vortec FMU, since it doenst have an ajustabvle onset, isnt enriching fuel until you build quite a bit of boost (cuz it sucks), so when it starts spooling at 3500 rpm, it goes lean, and then finally up at 5k when youre into some real boost, he FMU decides its time to add fuel.
If the BEGi unti is workinf right you should be able to tune it out muuuuch better. So at least the car will be safe.
Then get to work on the megasquirt
#5
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You're supposed to get the vacuum for the FPR from the stock FPR, t'ing off that little 2" line. If I remember correctly. Try that. Nothing else should come or go from the two fuel pressure regulators in terms of vacuum lines.
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This measurement was a fourth gear pull and I'm sure I was fully spooled to 5psi by 4500k RPM probably even earlier.
The Megasquirt would be ideal since I have some RC550 injectors I got from a friend for free, but I've yet to commit to the install and tuning that will be involved. I have no ability to tune the thing so I'm paying someone to steady state dyno tune it. Still, my resistance is weakening, especially now that I ordered the LC-1.
The Megasquirt would be ideal since I have some RC550 injectors I got from a friend for free, but I've yet to commit to the install and tuning that will be involved. I have no ability to tune the thing so I'm paying someone to steady state dyno tune it. Still, my resistance is weakening, especially now that I ordered the LC-1.
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In this pic I circled which line is going into the Greddy and it's coming off the manifold.
http://www.ihatethissite.com/images/...up-circled.jpg
So, if I'm being a giant a-hole and haven't hooked this up right can someone point out what line I should be looking for?
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The crazy thing is, I've been running it like this for 10k miles now! And I have at least 30 autocrosses with it like this!
Can anyone tell me if it makes a difference if the line for the Greddy comes off the manifold where I circled it? Looking at it I'm pretty sure it doesn't make a difference, but I guess I could be wrong.
Can anyone tell me if it makes a difference if the line for the Greddy comes off the manifold where I circled it? Looking at it I'm pretty sure it doesn't make a difference, but I guess I could be wrong.
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So, you T off the line going between the stock FPR and the manifold. That could make a difference if the pressure is really different coming off the other location.
In that case where does the line I'm using currently end up going to? In the above pic I'm not really sure I can tell where that is going to.
All they say in the BEGI instructions is that the signal line has to come from the intake manifold after the throttle body, which would seem to be what I'm doing.
Obviously it could be different for the Greddy.
In that case where does the line I'm using currently end up going to? In the above pic I'm not really sure I can tell where that is going to.
All they say in the BEGI instructions is that the signal line has to come from the intake manifold after the throttle body, which would seem to be what I'm doing.
Obviously it could be different for the Greddy.
#12
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I believe it also has to do with signal stability. T it off the FPR, see if it makes a difference. One of the two barbs by the throttle body fed my BOV, the other went into the cab, tee'd into the O2 clamp, and then to my boost gauge.
#14
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Sounds good. In the mean time, seeing as though it's free, change your vacuum location and disconnect your waste gate, or don't drive it. That'll keep the boost from building, and if it does build a little bit, since the waste gate hole is small on our turbos, it'll still hopefully add a little fuel if it does see some boost, which it will.
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You only need three things to tune anything, automotive or not.
1. Targets
2. Feedback
3. Controls of variables that affect feedback.
AFR targets can be found in several threads on this forum.
LC-1 will give you great feedback.
Now you need to familiarize yourself with the few controls you have over fuel delivery.
1. Targets
2. Feedback
3. Controls of variables that affect feedback.
AFR targets can be found in several threads on this forum.
LC-1 will give you great feedback.
Now you need to familiarize yourself with the few controls you have over fuel delivery.
#20
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Got the wideband installed and I replaced the Greddy AFPR with the BEGI AFPR. That seems to have things relatively under control in that I'm not seeing that hefty lean condition getting into boost anymore, but I do have to get back on the dyno to fine tune it a bit.
I'm sure everyone on here has money for a Megasquirt and dyno time, but I've seen the issues involved and I'm just not ready to go that route quite yet. Possibly next year, but I just replaced all the suspension for coilovers and swapped out the bushings as well so now I'm really ready to drive the thing for a while rather than figure out how to get it running with MS. I don't mind the low boost levels as long as I'm not going to blow the thing up.
I'm sure everyone on here has money for a Megasquirt and dyno time, but I've seen the issues involved and I'm just not ready to go that route quite yet. Possibly next year, but I just replaced all the suspension for coilovers and swapped out the bushings as well so now I'm really ready to drive the thing for a while rather than figure out how to get it running with MS. I don't mind the low boost levels as long as I'm not going to blow the thing up.