454mpi with procharger loses power ,smokes,etc...
06-14-2008, 10:10 PM
#11
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Not totally sure about the 454 MPI but that base fuel pressure sounds way high. I know that the mag motors run around 37 as a base. More fuel pressure will make it go WAY rich. It could be dumping a bunch of raw fuel in the exhaust
Ditto what Kenny said on fuel. Go with at least 91. Is the gas in the tank old?
Ditto what Kenny said on fuel. Go with at least 91. Is the gas in the tank old?
news:
the procharger has a small water leak in the intercooler.
that water has maybe done some damage ot valves.. the backfires i hear out of the intake ..maybe the bent valve or valves...
compression sunday !
new procharger intercooler is coming in with fed ex !
hope i dont need to yank the head or heads off.
06-15-2008, 01:35 PM
#12
it is new fuel.
news:
the procharger has a small water leak in the intercooler.
that water has maybe done some damage ot valves.. the backfires i hear out of the intake ..maybe the bent valve or valves...
compression sunday !
new procharger intercooler is coming in with fed ex !
hope i dont need to yank the head or heads off.
news:
the procharger has a small water leak in the intercooler.
that water has maybe done some damage ot valves.. the backfires i hear out of the intake ..maybe the bent valve or valves...
compression sunday !
new procharger intercooler is coming in with fed ex !
hope i dont need to yank the head or heads off.
Don't even try octane booster. It does not work.
I would look into the fuel pressure deal. That still sounds way too high.
Last edited by ZXXX Donzi; 06-15-2008 at 01:37 PM.
06-15-2008, 10:35 PM
#13
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You need to get some race gas and figure out how the correct ratio to get your octane up to 91. You can technically run 89 in a M-3 but I would not even think about it without forged internals. I am guessing that you have an M-1 with the AW 304 intercooler. You run 87 in an MPI with a M-1 Procharger and you will be back in the shop.
Don't even try octane booster. It does not work.
I would look into the fuel pressure deal. That still sounds way too high.
Don't even try octane booster. It does not work.
I would look into the fuel pressure deal. That still sounds way too high.
the intercooler is a aw-324 engine mounted.
what can b wrong that my pressure is too high ?
btw, we took compression today and i have 150+ all over with one at 170 .... so , i have no bent valves...
i noticed one plug had the tip bent with no gap at all.
we had the new plugs put in last week...
i think that explains the little backfires i had after they did the plugs... the spark must be occuring with difficulty and late and the combustion occuring after the valve opens up and i could hear this combustion in the intake through the throttle body...
does this make sense ?
06-16-2008, 11:13 AM
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06-16-2008, 05:34 PM
#15
I really hope that you are kidding about the whole Octane and fuel pressure issue. If you don't be careful you will fry that engine in a New York Minute.
Fuel injectors fire for a specific pulse width based on programming. For any given amount of time an injector stays open, a certain amount of fuel will be injected. The higher the fuel pressure, the more fuel. One way Procharger compensates for not using larger injectors and reprogramming the ECU is to use a boost reference regulator. That regulator reads boost and jacks up the fuel pressure to keep the engine from leaning. The typical ratio for them is 3 lbs for every 1 lb of boost. If your base fuel pressure is off then the issue will be compounded. That is why Brian asked if your regulator was sticking. It may be stuck
If your injectors are expecting a base fuel pressure of 37 psi and your are shoving 47 psi at them, you will be way rich and are shoving unburned fuel into the exhaust causing a backfire. You will also be fouling plugs etc.
Not to try to be demeaning, by I would recommend that you take your boat to someone that understands supercharged engines. If you don't know the importance of octane or understand that whole boost fuel pressure relationship then you are at risk of making a very expensive mistake. Right now it sounds like you are on the rich side. If you make these types of mistakes on the lean side and then give it some power bad things will happen quick.
Like I said earlier, I am not sure about the 47 lbs thing but it sounds way high.
Fuel injectors fire for a specific pulse width based on programming. For any given amount of time an injector stays open, a certain amount of fuel will be injected. The higher the fuel pressure, the more fuel. One way Procharger compensates for not using larger injectors and reprogramming the ECU is to use a boost reference regulator. That regulator reads boost and jacks up the fuel pressure to keep the engine from leaning. The typical ratio for them is 3 lbs for every 1 lb of boost. If your base fuel pressure is off then the issue will be compounded. That is why Brian asked if your regulator was sticking. It may be stuck
If your injectors are expecting a base fuel pressure of 37 psi and your are shoving 47 psi at them, you will be way rich and are shoving unburned fuel into the exhaust causing a backfire. You will also be fouling plugs etc.
Not to try to be demeaning, by I would recommend that you take your boat to someone that understands supercharged engines. If you don't know the importance of octane or understand that whole boost fuel pressure relationship then you are at risk of making a very expensive mistake. Right now it sounds like you are on the rich side. If you make these types of mistakes on the lean side and then give it some power bad things will happen quick.
Like I said earlier, I am not sure about the 47 lbs thing but it sounds way high.
06-16-2008, 08:07 PM
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I really hope that you are kidding about the whole Octane and fuel pressure issue. If you don't be careful you will fry that engine in a New York Minute.
Fuel injectors fire for a specific pulse width based on programming. For any given amount of time an injector stays open, a certain amount of fuel will be injected. The higher the fuel pressure, the more fuel. One way Procharger compensates for not using larger injectors and reprogramming the ECU is to use a boost reference regulator. That regulator reads boost and jacks up the fuel pressure to keep the engine from leaning. The typical ratio for them is 3 lbs for every 1 lb of boost. If your base fuel pressure is off then the issue will be compounded. That is why Brian asked if your regulator was sticking. It may be stuck
If your injectors are expecting a base fuel pressure of 37 psi and your are shoving 47 psi at them, you will be way rich and are shoving unburned fuel into the exhaust causing a backfire. You will also be fouling plugs etc.
Not to try to be demeaning, by I would recommend that you take your boat to someone that understands supercharged engines. If you don't know the importance of octane or understand that whole boost fuel pressure relationship then you are at risk of making a very expensive mistake. Right now it sounds like you are on the rich side. If you make these types of mistakes on the lean side and then give it some power bad things will happen quick.
Like I said earlier, I am not sure about the 47 lbs thing but it sounds way high.
Fuel injectors fire for a specific pulse width based on programming. For any given amount of time an injector stays open, a certain amount of fuel will be injected. The higher the fuel pressure, the more fuel. One way Procharger compensates for not using larger injectors and reprogramming the ECU is to use a boost reference regulator. That regulator reads boost and jacks up the fuel pressure to keep the engine from leaning. The typical ratio for them is 3 lbs for every 1 lb of boost. If your base fuel pressure is off then the issue will be compounded. That is why Brian asked if your regulator was sticking. It may be stuck
If your injectors are expecting a base fuel pressure of 37 psi and your are shoving 47 psi at them, you will be way rich and are shoving unburned fuel into the exhaust causing a backfire. You will also be fouling plugs etc.
Not to try to be demeaning, by I would recommend that you take your boat to someone that understands supercharged engines. If you don't know the importance of octane or understand that whole boost fuel pressure relationship then you are at risk of making a very expensive mistake. Right now it sounds like you are on the rich side. If you make these types of mistakes on the lean side and then give it some power bad things will happen quick.
Like I said earlier, I am not sure about the 47 lbs thing but it sounds way high.
one spark plug gap was completey shut. the were new installed last week. seems like they missed one !
this is where the backfire into the intake came from...we are almost sure.
i have a new intercooler landing anytime now. after it is installed , we will know for sure what it is we are looking at ! i need to check the fuel pressure using a gage on the fuel lines...just in case the one on the dash is bad.
06-16-2008, 08:23 PM
#17
compression is all fine, they scanned the computer today and found no errors.
one spark plug gap was completey shut. the were new installed last week. seems like they missed one !
this is where the backfire into the intake came from...we are almost sure.
i have a new intercooler landing anytime now. after it is installed , we will know for sure what it is we are looking at ! i need to check the fuel pressure using a gage on the fuel lines...just in case the one on the dash is bad.
one spark plug gap was completey shut. the were new installed last week. seems like they missed one !
this is where the backfire into the intake came from...we are almost sure.
i have a new intercooler landing anytime now. after it is installed , we will know for sure what it is we are looking at ! i need to check the fuel pressure using a gage on the fuel lines...just in case the one on the dash is bad.
I am staying with my you need to get someone that knows what they are doing comment.
06-16-2008, 09:20 PM
#18
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06-18-2008, 12:04 AM
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Ditto.....and I can almost gurantee the guage on the dash for fuel pressure is wrong.....either high or low. Back to the intercooler thing....don't really think this is a contributing factor to your backfire issue, and really don't think it has anything to do with your soot ,smoke problem. I am standing by my diagnosis of the FMU hanging open dumping fuel into the motor , are yo making any oil? and again you need to verify the FP @ the rail under operating conditions... Find a new shop that knows Blower motor set up ....but hey it's your motor.
Bryan
Bryan
once the intercooler is back, we will have the fellow install a mechanical fuel gage to really see what pressure it is showing.
06-18-2008, 08:13 AM
#20
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Good idea on the gauge. P/C says .028-.030 with a stock ign. If you run @.035 it will probably miss on the top end or under load. I run mine @ .030 AC MR42T's.
