roller cam motors with high spring pressures

[Jim Comet]

So as discussed in a prior thread, I am running a lot of spring pressure. About 650 open. This 416ci motor goes through the traps at 6900rpms. The motor has been running very well. This fall when I put it away for the winter, I was wondering if I should pull the T&D rockers and Crower lifters and send them in for inspection. They will have about 80 passes on them at that point. How often should I have them inspected if I am not having any issues? Thanks Jim

[jayb]

Jim, I'm not sure that T&D will be able to tell if the rockers are close to the limit.  With only 80 passes, I doubt that they are.  Eventually with enough spring pressure all aluminum rockers will fatigue and break, but your pressures are not that high.  If you are concerned I would take them off and make sure the shaft bearings and the roller tips feel OK, and if so, reinstall them.  My approach to this issue, when I was running T&D race rockers, is to just buy a couple spares so that when one of them breaks you have a backup.

[Jb427]

I am around the same spring pressure as you Jim I have not bothered to look into my resent brakeage as I am still waiting for replacement and some spare rockers. My shaft bearing and tip was perfect I will do as Jay and remove them all have a good look and reinstall them. The more times I look at the photo of how mine broke the more I think it was just a bad rocker

Here is a close up of the area Mine are 3000 street miles old when I went back and looked.

[hbstang]

as for the roller lifters i would send them in to at least get checked out.broken lifters destroy engines at 6900 rpm.

[dozz302]

As per the title of this thread > HIGH BREAKAGE RATE & High Maintenace > END

[bluef100fe]

My aluminum T&D race rockers have survived since 2017 in my 520 and the springs are around 250 on the seat and over 700 open, .700ish lift cam and seen north of 7000 rpm alot… plenty of passes and street miles on my deal. Engine is apart now for a freshening. Crower bushed lifters looked surprisingly good after that amount of time. 100’s if not a 1000 passes and several thousand street miles… some pulling a trailer or the boat to the lake lol. Love driving my old truck. I wouldn’t be worried yet on yours. T&D and Crower make some very good stuff.