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replace fuel injection with carb?

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Old 08-21-2002, 11:50 PM
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Default replace fuel injection with carb?

I have a 99 7.4l mpi(310) has anyone replaced the fuel injection with a rpm manifold and carb? is there any hp gains to be made there?
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Old 08-22-2002, 12:43 AM
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Why would you want to do this? By just replacing the injection I would think you would loose 10 hp. The carb version is 300hp. Can you add a cam and other things maybe to help out? I think maybe but I would think your overall driveability would go down

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Old 08-22-2002, 06:42 PM
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Ive heard the 310s injection is not that good and wanted some feedback to see if that an issue
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Old 08-23-2002, 01:11 PM
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I have a carbed 7.4 and an MPI one with a good 4 bbl manifold exhaust etc the carb puts out more power and is easy to work on. However if the MPI was laptop adjustable thats the way I would go.
 
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Old 08-23-2002, 04:08 PM
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One thing that can NEVER happen with a carb is : melt a piston down due to a single injector clogging up. Unless the fuel injection is throttle body type. EFI is extremely efficient.....when it work right. Any problem can bring rapid trouble!! That's what happened to me....
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Old 08-23-2002, 06:04 PM
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I would think that simply changing the induction system would not net you any gains at all. If you are going to change to a carb., you would have the ability to either change the heads or at least re-work yours, and do a cam change. That way you can take advantage of a carbs ease of tuning and see a real increase in performance. I have said it on many other posts here.....I don't trust companies who claim to be able to re-map your ecu for any changes you have made to the internals of your motor. So, if your plan is to change to a carb go for a few more changes and make use of the main advantage that a carb has over efi, tuneabilty..

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Old 08-23-2002, 06:33 PM
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Check- Will ya get off the improperly re-mapped ECU thing?!! It's not the same as changing jets!...Band-Aid closed loop at best...Motors aren't blowing because of faulty programming...PERIOD!! Other reasons...sorry to be a puss, won't be back until Monday...talk to ya then. Love to All, Liquid.
 
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Old 08-24-2002, 10:05 PM
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Default swap EFI for carb

Most any engine builder will say that the Merc fuel injection system has certain limitations as far as making any big power. A carb setup probably has greater horsepower potential. But for me, I like all the other benefits from EFI. Easy starting, no fouled plugs, much broader torque curve, and a few other things. Your setup may not be a prime candidate for attempting to make big power via carb/cam/intake change. If your 454 EFI is not doing what you want, maybe a trade for a 502 EFI with a few mods done for reliability is what you need. That would be a big power upgrade.

Then again, you probably could purchase everything you need for the changeover by selling your complete EFI setup.

Good luck.
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