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?

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

Jon

Ive heard the 310s injection is not that good and wanted some feedback to see if that an issue

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.

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....

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..

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.

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.