5.9 magnum poor perf

[cwkerr007]

have a 2000 5.9 with eq heads 202 valv ported edy air gap 750 holley nv3500hd 3:91 28"tires stock dist with gm module y pipe to dual out muffler ......... now it is running perfectly and have tied every timing change but still is a slug in my opinion... I have owned several sbm engines and this is a pig!! If u can get it wound up it has a small burst of power above its nomal operating range. most of my 318's would have left this thing in the dust. It does have more power in 5th at 30mph than any one I owned and it pulls great but it neve gets to that ah ha moment. It sounds geat like it will light the tires on fire but it just doesn't and won't lay ubber on road unless you get the tires wet and get it wound up and even then it is a short lived burst before it grabs and goes. Ive put all diff size tires on it trying to change ratio and its still a pig haven't smelled rubbe since it started WHAT IS WRONG WITH THIS PIG????????

 

[Daw14]

Maybe your distributor is not functioning correctly.

What’s it doing in 5th gear at thirty miles an hour ?

 

[diymirage]

When you (or whoever) installed the cam was it degreed or just dot to dot?

 

[Dodge59]

I did a rebuild one time, and knew i should be getting 252 HP )1957 Pontic Super Chief. Any ways is sounded a lot like your issue, but it turned out to be a Vacuum leak between the New Carb and the intake manifold. Tighten down the Plate and WOW- what a difference! I hope you issue is that simple. (It took me a week to find the issue after adjusting the Valves a bunch of time... Dd i feel like a fool! Screeching tires for 3 blocks made me feel better!.

 

[RodeoRam]

One possibility for your lower HP could be the PCM death flash Dodge did to the 2nd Gen 5.9s back in the early 2000s. It retarded the engine timing to stop spark knock. I know when the dealer did it to mine (without asking) that the power in my 2001 1500 5.9L dropped considerably.

Some info here. You can also search for TSBs like this one for the 1999 Rams.

 

[Russ89123]

What did you hope to gain by removing the fuel injection and installing a carburetor?