Iron Horse

My VP is slowly dieing, dead pedal, low power, erratic throttle response, all the normal codes, etc.

The question I have is do I put an HO pump back on it, or will an SO pump work? Reason I want to do the SO is for more power potential, as the HO pump tends to peak at about 500-550HP, where as the SO pump is capable of more.

HOHN

Stick with the HO.

Iron Horse

Kinda what I have been thinking, more for simplicity sake, but is there a reason? I would think that the higher HP potential would make it worth the switch.

JAFAW

The HO and SO have different heads, different cam rings, and program different on the stand. You need to stick with the HO if that is what you have.

caleb c.

Can't he put a HR VP-44 in it?

Iron Horse

$600-700 difference in price, and the HR is no more reliable then a stock pump, and have yet to see hard evidence showing the hot rod pump makes more power then a stock replacement

Iron Horse

Heads, cam gears, etc are the same between the two engines, only differne that I know of is a smaller plunger on the HO pump, then the SO, and the HO has a slightly higher compression ratio, do to differnt pistons. (16.3-1 to 17.0-1). This come from the info at dodgeram.org.

As far as pump calibration, the VP44 is calibrated to a certain keyway on the shaft, to set the proper base timing, not speciffacly to a certain engine. The power differnece comes from the higher pressure of the HO pump, but overall lower volume then the SO pump.

95ram

I was told by TST that the HRVP would make about 60HP more than stock. It also gives you the full gains of any performance box. ie. instead of only getting 90RWHP from a comp or pmax you'd get the advertised 125/130, what ever it is. It would also allow you to run the drag comp or TST comp which from what I understand neither are recomended with the stock HO pump. Someone please correct me if I'm wrong.