Replacement injectors for 861260T (502MPI Whipple)
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Replacement injectors for 861260T (502MPI Whipple)
I would like to replace these injectors with ones that flow more (to get rid of the enrichment injectors in the Whipple system), does anyone know of any injectors that fits?
#2
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Tomas,
I am not familar at all with the Whipple system, but I wonder if those extra injectors are used to lubricate the rotors? Or are they below the blower?
I purchased Trick Flow injectors from Summit. They are flow matched to 1% and I was given the opening time from the engineers at Trick Flow. That was good info to have for my EFI.
I am not familar at all with the Whipple system, but I wonder if those extra injectors are used to lubricate the rotors? Or are they below the blower?
I purchased Trick Flow injectors from Summit. They are flow matched to 1% and I was given the opening time from the engineers at Trick Flow. That was good info to have for my EFI.
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I don't believe the side mount whipple blower need fuel for lubrication?! But I might be mistaken.
Eddie, I don't know what size I need yet. Trying to figure out what injectors that fit to start with.
Howe much power will the stock injectors and stock fuel pump be able to handle with an increase in fuel pressure and a re map?
Eddie, I don't know what size I need yet. Trying to figure out what injectors that fit to start with.
Howe much power will the stock injectors and stock fuel pump be able to handle with an increase in fuel pressure and a re map?
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Tomas-
If you have side mount Whipples and remove the extra injectors, you do lose some of the cooling effect that is gained by injecting fuel into the airstream ahead of the blower.
I have side mounts and have already done what you are planning. My setup works very well. I bought my injectors from www.fiveomotorsports.com . They are made by Siemens and fit perfect and have a great spray pattern. I think they are 65 lb/hr. rated. They will work with the stock Merc MEFI 3 computer.
Make sure if you order a set that you have them flow a set and get 8 that match.
Pm me for more info or we can talk via phone and I can help you with your setup.
Smitty
If you have side mount Whipples and remove the extra injectors, you do lose some of the cooling effect that is gained by injecting fuel into the airstream ahead of the blower.
I have side mounts and have already done what you are planning. My setup works very well. I bought my injectors from www.fiveomotorsports.com . They are made by Siemens and fit perfect and have a great spray pattern. I think they are 65 lb/hr. rated. They will work with the stock Merc MEFI 3 computer.
Make sure if you order a set that you have them flow a set and get 8 that match.
Pm me for more info or we can talk via phone and I can help you with your setup.
Smitty
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This might also help. His part number is 107962.
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Last edited by Smitty; 01-04-2011 at 08:57 PM.
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If you are using a side mount WHipple, then you will want to keep the extra injectors in the blower. Not only do they help cool the blower, but they also help it to seal. The rotors can only be so close without touching each other. There has to be some room between them. The fuel will help to close that gap up and make a better seal.
In the side mounts that I have done, I used (2) 80# injectors in the blower, along with the stock injectors in the intake. With that and a 2000 cfm throttle body, I was able to make well over 700 hp. If you are running a side mount and still using the stock throttle body, then you will have problems busting 700 hp. If that's the case, then the additional 80# injectors will be more than enough.
What is your setup? What blower? Side mount? What other mods? How much power are you looking to make? I need more info to tell you which way to go.
Eddie
In the side mounts that I have done, I used (2) 80# injectors in the blower, along with the stock injectors in the intake. With that and a 2000 cfm throttle body, I was able to make well over 700 hp. If you are running a side mount and still using the stock throttle body, then you will have problems busting 700 hp. If that's the case, then the additional 80# injectors will be more than enough.
What is your setup? What blower? Side mount? What other mods? How much power are you looking to make? I need more info to tell you which way to go.
Eddie
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I bought a pair of used 502MPI's (#0M36) with side mount Whipples and one of them are missing the injectors and the fuel pump and according to the seller both of them had burnt one or two pistons (I haven't had the time to tare them down yet but will do in the next few weeks).
Unfortunately I don't know what caused the burnt pistons, if it was bad fuel, bad injectors, bad fuel pumps but since it's both of them I'm guessing on bad fuel...
I'm not looking to get more than 650HP out of them but wan't it reliable. How much power will the bottom end put up with??? What is the weak link, crank or rods?
Is the stock fuel pump really enough?
I'll get you more detailed info when they're torn down!
Unfortunately I don't know what caused the burnt pistons, if it was bad fuel, bad injectors, bad fuel pumps but since it's both of them I'm guessing on bad fuel...
I'm not looking to get more than 650HP out of them but wan't it reliable. How much power will the bottom end put up with??? What is the weak link, crank or rods?
Is the stock fuel pump really enough?
I'll get you more detailed info when they're torn down!
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As for the fuel system, Whipple added a seperate small fuel pump just for the 2 additional injectors in the blower. It was it's own seperate fuel system. I do away with all of that and the stock fuel system and replace it all. The way to do it is to run one larger pump. The stock pump is not enough. An Aeromotive A1000 pump will work just fine. There are several other pumps that will work as well.
The stock injectors in the intake and 2 80# injectors in the blower are the way to go. You really should do some mods to the fuel rail. There is one injector that has a VERY small feed hole going to it. That one cylinder has a tendency to run lean. That injector feed hole needs to be opened up. Also, I drill and tap the ends of the rail for larger fittings and hoses. The stock hoses are very small. I also feed fuel to the rail from both ends. I also drill and tap a bypass hole in the rail for a return. It depends on which rail you have. They made 3 different versions over the years. Some are easier than others to modify. If the rail has a built in regulator, then it will need to be removed and a seperate remote mount regulator used. An Aeromotive regulator is fine. I would be glad to do the mods to your rail if needed.
I use the one fuel pump to supply both sets of injectors and then return to the tank. You also need to get rid of the stock fuel filter head and replace it with a larger one if it already hasn't been done.
The bottom end will certainly handle the 650 hp you want to make. The crank and rods are more than strong enough for that. It previously burned a piston because it was lean. Whether it wasn't tuned correctly or the fuel system could not deliver the fuel, it was too lean.
That will get you started in the right direction. Feel free to contact me if you have any more questions or if I can help.
Eddie
The stock injectors in the intake and 2 80# injectors in the blower are the way to go. You really should do some mods to the fuel rail. There is one injector that has a VERY small feed hole going to it. That one cylinder has a tendency to run lean. That injector feed hole needs to be opened up. Also, I drill and tap the ends of the rail for larger fittings and hoses. The stock hoses are very small. I also feed fuel to the rail from both ends. I also drill and tap a bypass hole in the rail for a return. It depends on which rail you have. They made 3 different versions over the years. Some are easier than others to modify. If the rail has a built in regulator, then it will need to be removed and a seperate remote mount regulator used. An Aeromotive regulator is fine. I would be glad to do the mods to your rail if needed.
I use the one fuel pump to supply both sets of injectors and then return to the tank. You also need to get rid of the stock fuel filter head and replace it with a larger one if it already hasn't been done.
The bottom end will certainly handle the 650 hp you want to make. The crank and rods are more than strong enough for that. It previously burned a piston because it was lean. Whether it wasn't tuned correctly or the fuel system could not deliver the fuel, it was too lean.
That will get you started in the right direction. Feel free to contact me if you have any more questions or if I can help.
Eddie
Last edited by Young Performance; 01-05-2011 at 09:44 AM.