Has anyone experiance knock related to roller rockers? I am having knock counts and timing retard that doesn't seem to have a logica source. It seems to occure in a 1200-1800rpm range regardless of load (LV8~ 156 $6E-MAF) The rockers I am using have a noticable "mechanical" sound which is more noticable at this rpm range. Any thoughts or comments?

 

Are they seated and tightend properly? i just finish building my new engine had them seated real nice broke the engine in for about 20 min and now im going back in to re adjust them.

 

yeah I don't have a lot of miles yet but pulled a cover and re-adjusted that side and they were spot on. Still a lot of "noise" associated with them but definatly no lash.

 

were they noisey? I am in a similar situation with approx. 20 mins run time for break in and I hear a noise coming from the #8 cylinder.

 

I don't know how "noisey" I'd call them. Not a "tic" like they need adjustment and not like a solid lift cam. More like rattley. If you remember the sound an old-time roller skate wheel would make when you spin it- that would be the closest I could explain. The sound of an open ball bearing. It's about the same decible level as the injectors make. When I close the hood you can't hear them but it's just loud enough to notice when driving by a highway barrier or wall. And just enough in my opinion to ask the original question.

Has anyone else seen knock retard that they attributed to the roller rockers? This "rocker" discussion is great but not the core issue of my thread.

 

Have not had any issues with my roller rockers relating to Knock .... If you confirm it is the rockers causing your issue, I would certainly look into the type and condition of your rockers .....
Are they full roller, or roller tips ???? I've heard of issues with the roller tip rockers .....

 

I've used Crane aluminum full roller rockers, Comp Cams steel full roller rockers, and Comp Cams cast roller tip rockers with no issues with the knock sensor. These were all on hydraulic flat tappet cams.

If you used Comp Cam 853 lifters (hydraulic roller) that is most likely where the noise is coming from.

RBob.

 

Thanks guys. These are full-SST roller rockers. The "no-name" brand from Skip Whites. They are brand new with maybe 100 miles, if that. They seem to be of decent quality and no, I have not linked them to my knock retard issue just yet. Pretty much a suspicion I was hoping to rule out. Thanks for the replies and I will let you know when I learn more.

So far I have pulled a lot of timing out in the low rpm/lv8 ranges. This is where I get most of the timing retard. I am now dumping more AE in to see if that may be a part of the problem. This is a 165/MAF car with a TKO 5-speed/3.70 gear. Spends a lot of time in the 1200-2500rpm range when crusing in 5th and is kpet there due to the stick shift application.