well as you may have noticed i have a 02 with a ho cummins. the pump went out and i replaced it was a ho pump. one year later the ho pump goes out again. i think about a hot rod and ask some guys on here and they tell me to go with a so pump(235hp) over the 245hp. i ordered the so pump and installed it today. only took 3 hours using nothin but hand tools. anyways i was gonna tell the results. there is a definite notice in low end loss goin from the ho to so...injectors i hear will fix that. mine seems to idle a bit weird also. just doesnt sound the same, also when im drivin and i push in the clutch it goes to about 1000rpm and then when i stop it drops down to about 780 rpm. it does seem to run pretty smooth down the highway though so far. plenty of high end power. can wait for injectors!

 

The SO pump has larger pistons than the HO pump but the HO pump has a more aggressive cam. Because of the SO pistons, they can make more power than the HO pump. I understand that the hot rod pumps are SO pumps with HO cams.

 

whats with the weird 1000rpm when i push the clutch and idle down when i let off

 

when i stop is what i meant to say...got distracted with something else while i was typin

 

If I understand you right, when you're driving down the road and you push in the clutch, the RPM's will drop to only 1000 RPM and remain there until you come to a stop (with the clutch still in) and then the RPM's will drop to the normal idle speed? Do you have to come to a complete stop or do the RPM's drop to normal at some slow speed? Does it do it when you just slip it in neutral or only with the clutch in?

 

ya when i go to stop at a stop sign it dont matter if i push in the clutch or just take it out of gear it will go to 1000rpm until i come to a complete stop then go to about 800 rpm or so. its still runnin at a higher idle than my ho pump did. not sure if this is normal or not

 

No, thats not normal. Sounds like something elses isn't right. Does your speedo act normal?

 

yep everything works just fine. worked just the same as it always has other than the idle goin up like that. it seemed like my ho pump idled at about 700-750 and this one is about 800. my buddy has an 02 that is the exact same year, bodystyle, and trans as mine and he has a bd pump on his and his does the exact same thing

 

Hmmm..... Idle should be about 825-850 RPM. And I still have never heard of this happening when installing an SO pump on a HO motor. Maybe your Quadzilla is playing a part? I'd be calling some VP vendors and asking if this is normal.

 

well maybe it did idle at 825 850..i was just kinda lookin on the tach and tryin to guesstimate on it. im thinkin my ho pump wasn't right and that i was just used to its idle then when i put this new one on that has a correct idle its got me worried. it performs perfect. just was wonderin about that idle thing.