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Hi all, it's been a while. Turbo motor has been running great, had to tear it down as one of the cylinders was weak plus I wanted to see how everything was doing. I've ran e85 for about 2000 hard miles. So far the original cam which is basically a web 494 equivalent with 112LC had some pitting on the front lobe so it took out the lifter. The other lifters have a wear line across the middle of almost each lifter, best I could come up with is they didn't rotate? I'll have to look at my geometry again, maybe I missed something on the first go around. I have an actual with web 494 with 108LC with their mechanical lifters on the way. One thing I've never seen before appeared on all the cylinders. These lines are appearing on the meat of the cylinder and seem to follow the cooling fins - what's going on? Whatever it is its definitely not all the way through. Think a hone can clean it up? I had some special sauce done to them for sealing so I would rather not replace the set if possible.


picnic logo images

Talk to AA. I don't mean that rudely, but I think they'd want to see that. Then they could tell you how to proceed.

H2OSB

I have an email in - let's see what they say

AA is sending a new set of pistons. We worked it out, I'll be sending them one for them to look at. They haven't seen something like this.

It wouldn't be your rocker geo. How well do the lifters spin in the bores ? And what oil did you use ? You know you need the oil with minerals (ZDDP) like zinc and phosphorus to name just 2 of them, to allow the cam lobe to rotate the lifter.

sweetlokin66 wrote: ↑Fri Jan 10, 2020 10:05 am AA is sending a new set of pistons.

Pistons or cylinders?

Some of those marks look like a combination of casting flaws w/potential thin spots causing cracking or weak/thin spots. A lot of what I am seeing in the metals (et al) mix now days fills me with suspicions like they (and they means at a lot of different levels of business) aren't necessarily complying with the specs that cover the making of the specific material itself assuming they are going by a ANSI/USASI or ISO specification.

Lee

cast iron?or aluminum cast nickies? witch ever thats not good. Im looking for some dead wore out cast aluminum nickies or brial
s I can sleeve down to 94's. as for the lifters...is the clearance good? broken in properly? correct taper on cam& lifters? good oil?

While its down get your lifters ground with more "crown" to promote spinning.