Did not have this issue before, I actually ran more pressure na at the regulator than I am right now.
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I'm with Noobz. The the idle and cruise under control and address the WOT after that. You should be seeing about 14.7 at cruise under light pedal, no matter what the speed and your idle should be about the same. If anything, your cold start idle should be a little rich. Once you've got that dialed in, then take a look at your FMU.
I have a suspicion your FMU isn't functioning. Seeing 13.5-14.2 at WOT is N/A numbers....heck, it's even lean for WOT N/A numbers. For optimal power and drivability, should be seeing between 12.8ish-13.5 N/A and in the 11.5-12.0 range with the blower. Are you certain the FMU is functioning correctly? I'd try tee'ing it off and hooking a vacuum/boost gauge to it to ensure that it's even functioning properly? Who knows....maybe you've got a line on incorrectly and aren't seeing enough pressure to activate it?
This causes me to wonder: Was your car digitally tuned while pressure at the regulator was this high?
If your tuner thought that this was where the fuel pressure needed to be for your injectors and motor combo, then you may be flat out of injector.
If it's true that previously, fuel pressure was elevated, the 8:1 diaphragm just became a 5:1 diaphragm with diminishing returns.
I highly doubt my little iron headed cobra intake 306 needs more than 30lbs of injector........ but seems that way don't it....
New set of 42# on ebay are only 160$.....
Then a tune 300-600$..
Or the mega squirt 415$
New set of 42# on ebay are only 160$.....
Then a tune 300-600$..
Or the mega squirt 415$
Let me clarify somethings
My current fuel pressure at the regulator is 36 with vac off to lean out the idle cruise.
On my na setup I ran 40# with no vac on the regulator.
The question is why has the engine loaded up on fuel?
Things that have changed.
Different plugs colder range smaller gap
Higher octane fuel 93
The supercharger piping
The filter no longer has a shroud over it, maybe fan wash is skewing the reading?
High pressure 255lph fuel pump. The old one was the stock 90lph..... lol
My current fuel pressure at the regulator is 36 with vac off to lean out the idle cruise.
On my na setup I ran 40# with no vac on the regulator.
The question is why has the engine loaded up on fuel?
Things that have changed.
Different plugs colder range smaller gap
Higher octane fuel 93
The supercharger piping
The filter no longer has a shroud over it, maybe fan wash is skewing the reading?
High pressure 255lph fuel pump. The old one was the stock 90lph..... lol
Tried today.....
-Shrouded the filter with some abs plastic sheeting to stop fan wash.
-increased fuel pressure to 40# vac off.
-timing back at 10* base
-shot 5psi into the fmu at idle pressure increased to 80lbs.
-changed the location that I got my boost reference from (put a vacuum T on the fpr then down to the fmu).
Still have lean condition, cruise afr is in the 14 range, idle 13range, wot 13.5-14.4?????
With 30lb injectors and a fmu this should not be an issue.........
What is the cheapest self tuning option??? Moates? Tweecer? I still want the ms tho.
-Shrouded the filter with some abs plastic sheeting to stop fan wash.
-increased fuel pressure to 40# vac off.
-timing back at 10* base
-shot 5psi into the fmu at idle pressure increased to 80lbs.
-changed the location that I got my boost reference from (put a vacuum T on the fpr then down to the fmu).
Still have lean condition, cruise afr is in the 14 range, idle 13range, wot 13.5-14.4?????
With 30lb injectors and a fmu this should not be an issue.........
What is the cheapest self tuning option??? Moates? Tweecer? I still want the ms tho.
Ok... You are seeing the fuel pressure rise on the gauge when you get into the boost.
Is that a true statement?
Is that a true statement?
I've got a couple of theories working around in my head but you'll have to verify them somehow;
1. You need to find a way to watch fuel pressure and boost rise. It's really the only way to ensure that the FMU is doing what it's supposed to do when it's supposed to do it. My thought here is that the diaphragm currently installed is not a high enough ratio.
2. Fuel pump can't handle the pressure: Could be a weak pump, it could be that power to the pump is falling off. If you're running a Walbro 190, I'd swap it. They have a tendency to bypass internally
2 65ish psi. If 255L or 255L High Pressure, I would pull voltages at the pump with lights and fan on then again with lights and fan off. Easy place to do this is at the relay under the seat. If the differences are significant then you may need something like a boost-a-pump to regulate voltage to the pump. If you're going with 42's then this should not be necessary.
3. Vac/boost gauge causing lean condition, if there is one.
That's all I got for now. Lemme know.
1. You need to find a way to watch fuel pressure and boost rise. It's really the only way to ensure that the FMU is doing what it's supposed to do when it's supposed to do it. My thought here is that the diaphragm currently installed is not a high enough ratio.
2. Fuel pump can't handle the pressure: Could be a weak pump, it could be that power to the pump is falling off. If you're running a Walbro 190, I'd swap it. They have a tendency to bypass internally
2 65ish psi. If 255L or 255L High Pressure, I would pull voltages at the pump with lights and fan on then again with lights and fan off. Easy place to do this is at the relay under the seat. If the differences are significant then you may need something like a boost-a-pump to regulate voltage to the pump. If you're going with 42's then this should not be necessary.
3. Vac/boost gauge causing lean condition, if there is one.
That's all I got for now. Lemme know.
2 is done already.
Gss342 255 hp model. Unless I got a bad one
And its already in the tank
Gss342 255 hp model. Unless I got a bad one
And its already in the tank
Bad part from supply is possible but not very likely IMO.
Power would be next thing to check. Check to see how much power dips while accessories are turned on and off. You'll need to override the pump motor via the connection at the firewall. If you're not sure what I'm talking about, JRichker has a pictorial diagram of it somewhere. I'll pull one up if you need it or can't find it.
Unless I'm missing something (not at all unlikely) this would be the last thing that we can really check without taking something apart and/or spending money.
Even though you have the correct diagram (the one indicated on paper) it doesn't rule out that it's not a large enough ratio. That I think, would be the next thing to look at BUT ONLY IF you're planning on skipping the 42's and tune.
Skip over any tuning system that is a TwEECer or even remotely like it in terms of user tuning. I consider myself to be a pretty tech savvy person. To make a really long story short, all I wanted to do was set that POS on-top of a fence post and shoot it till I was out of bullets. The hardware is all very first gen and the software is the geek project of a group of guys who swear it's the greatest thing on the planet.
If you want a another effin hobby. Buy a TwEECer.
After that experience, I had it chip tuned on a real dyno, by a real tuner who had specific experience with the equipment he was using (these are ALL qualities that I did not possess). I gave the man my $500+ and drove that mofo all the way home (2 hour drive by sane people) giggling like a bich who just smoked pot for the first time.
Since then, I've used an Anderson PMS on a couple of different cars. Pretty simple beast. That is all.
These other guys will have to get you about MOATS and QH, and all the others. Different features, different abilities, different ways of doing things. Some are verynice and a lot more advanced than the two systems that I've used.
Power would be next thing to check. Check to see how much power dips while accessories are turned on and off. You'll need to override the pump motor via the connection at the firewall. If you're not sure what I'm talking about, JRichker has a pictorial diagram of it somewhere. I'll pull one up if you need it or can't find it.
Unless I'm missing something (not at all unlikely) this would be the last thing that we can really check without taking something apart and/or spending money.
Even though you have the correct diagram (the one indicated on paper) it doesn't rule out that it's not a large enough ratio. That I think, would be the next thing to look at BUT ONLY IF you're planning on skipping the 42's and tune.
Skip over any tuning system that is a TwEECer or even remotely like it in terms of user tuning. I consider myself to be a pretty tech savvy person. To make a really long story short, all I wanted to do was set that POS on-top of a fence post and shoot it till I was out of bullets. The hardware is all very first gen and the software is the geek project of a group of guys who swear it's the greatest thing on the planet.
If you want a another effin hobby. Buy a TwEECer.After that experience, I had it chip tuned on a real dyno, by a real tuner who had specific experience with the equipment he was using (these are ALL qualities that I did not possess). I gave the man my $500+ and drove that mofo all the way home (2 hour drive by sane people) giggling like a bich who just smoked pot for the first time.
Since then, I've used an Anderson PMS on a couple of different cars. Pretty simple beast. That is all.
These other guys will have to get you about MOATS and QH, and all the others. Different features, different abilities, different ways of doing things. Some are verynice and a lot more advanced than the two systems that I've used.
I have Kenne Bell gauges (no idea who actually makes them) and it does not bounce... ever. I wish all my gauges were as nice.
Is yours electric or direct read?
Ok... slightly different animal but a very similar fix unless the gauge is actually bad.
Put a flow restriction in-line with your gauge. Hell, there's a ton of things I can think to try. I usually start with a plug of some kind that fits the vacuum line well and drill the smallest whole in it that I have a bit for. If gauge response is too sluggish, I drill it out the next size larger until I'm happy with it.
No vacuum lines on a fuel rail.......
Jk. I will try that tho....
May have a bad fpr..... line smell slightly of fuel.. when I prime the pump you can actually hear fuel moving thru the rail, the pressure spikes to 42 then when the pump stops priming it falls down to 36. Leaks down 1lb per minuet.
Jk. I will try that tho....
May have a bad fpr..... line smell slightly of fuel.. when I prime the pump you can actually hear fuel moving thru the rail, the pressure spikes to 42 then when the pump stops priming it falls down to 36. Leaks down 1lb per minuet.
I am leaning tward a bad fpr..... new piece of vac hose and after 5 mind idling the hose has a hint of fuel in it.... this may be my rich idle.
I shot compressed air into my boost gauge and adjusted it till I got 3# of boost. (Which is hard to do with a 150# regulator)
Then hit the fmu with that 3#... saw 46# of fuel pressure.....
Since I make 3-4 with the pulley setup I have, I can say with some certainty that it's not enough. So I am ordering the vortec master kit 69$ comes with all the pressure discs and a rebuild kit. I think the 10:1 disc is what I need.
Also getting new Kirban afpr.... it's obvious that it's gone bad.
Then hit the fmu with that 3#... saw 46# of fuel pressure.....
Since I make 3-4 with the pulley setup I have, I can say with some certainty that it's not enough. So I am ordering the vortec master kit 69$ comes with all the pressure discs and a rebuild kit. I think the 10:1 disc is what I need.
Also getting new Kirban afpr.... it's obvious that it's gone bad.