High RPM Mods

[Greenleaf]

Hi guys. Question for some of you who run in the mid 3,000 rpm bracket.



What do I "HAVE" to modify to ensure against destruction? The only one I'm aware of is heavy duty valve springs. What exactly do I use? My local shop has like no idea. I guess I'll just call PDR like I always have



Another mod is the dampener. My Cummins book lists two types. General duty/speed (for lack of a better term) and the heavy duty/high speed unit. I don't recall the exact rpm range of the latter, but the former isn't recommended much above stock/factory speeds.



What do you recommend there? I'm not running in the mid 3's often. Only rare occasions, but don't want to throw off any important parts when I am know what I mean... ... ... .....



Thanks guys.



Scott

 

[CDegner]

Not gonna say it hasn't happened, but I've never heard of a dampener coming apart. If you felt you really needed one, I believe there is a marine one rated for higher RPMs than the truck versions.



Carl

 

[JLEONARD]

Yes. The marine Diamond Performace series 370 hp version is rated at 3200 rpm.

Jay

 

[HFletcher]

JLEONARD, do you have a part number for the 3200 rpm dampener? Thanks, Hank

 

[Greenleaf]

I called PDR and one of the guys there straightened me out as always However, by posting here, all may learn.



I did not ask for a part no of the springs but they have them. No biggy there, as in not tough to do nor are they big $$. Recommended above 3,300 rpm I think he said... ... ... ... ... .



The dampener. The factory unit is used. He told me these engine are running 4,000 revs with no side effects. However, I don't know why the Cummins Service Manual lists two different styles.



Scott