454 L29 1997 moves to next stage of repair
So the trouble started last September when a fill up in NJ, (55 gallons), yielded a pinging and suspected bad gas. Then with confirmation it was not the gas, and after idling with octane booster, the ...
Forum Discussion
Daveinet,
Any diesel spec oil addresses the flat tappet issue. If you really want the most ZDDP in your oil the original Delo 400 is available in 5 gallon pails. However, to much ZDDP will slow ring seating in a new engine. The point I was making on the roller lifter is that the original install recommendation would lead a novice to think they can just be dropped in while the manifold is off. No mention is made about the material difference in the cam, the choice of cam gear (grafted or not), the difference in lobe profile, controlling the thrust and lifter design choice. Also remember that roller lifters do not like to be used in situations where there are extended periods of idleness. When the engine sits the oil drains out of the rollers and start ups are a bit tough on the needle bearings. This along with cost were the primary reasons it took so long for rollers to get in to production. The roller lifter failure rate was finally offset by CAFE penalties and the materials needed to produce a good lifter finally became affordable.
Randy
Any diesel spec oil addresses the flat tappet issue. If you really want the most ZDDP in your oil the original Delo 400 is available in 5 gallon pails. However, to much ZDDP will slow ring seating in a new engine. The point I was making on the roller lifter is that the original install recommendation would lead a novice to think they can just be dropped in while the manifold is off. No mention is made about the material difference in the cam, the choice of cam gear (grafted or not), the difference in lobe profile, controlling the thrust and lifter design choice. Also remember that roller lifters do not like to be used in situations where there are extended periods of idleness. When the engine sits the oil drains out of the rollers and start ups are a bit tough on the needle bearings. This along with cost were the primary reasons it took so long for rollers to get in to production. The roller lifter failure rate was finally offset by CAFE penalties and the materials needed to produce a good lifter finally became affordable.
Randy
