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I'm having a hard time understanding my old compression test numbers. Leak down being fine I get, as long as the valve close leak down is good regardless of timing but why the heck the compression looked good I'm confused....I guess but I screwed up in such an odd way with one can advanced and one retarded but ???
first CR test was
1-158
2-165
3-125
4-155
5-150
6-170
7-175
8-140 (this is the cylinder that eventually failed)
9-170
10-165
11-175
12-175

last CR test before failure
1-153
2-155
3-140
4-160
5-152
6-170
7-153
8-110 (this is the cylinder that eventually failed)
9-150
10-150
11-162
12-160
not great but I figure the rings needed to seat but nothing about bank 2 that would have clued me about the cams.

Timing cover time....and this is the job from hell on this engine.

First up, a stud for the timing chain drive pulled out on the last test fit so it needed to be helicoiled. I like to fit or make a drill block to be sure it stays straight



Then the bank 2 head gasket was sticking out a little bit so that had to be filed off


Then the fun really begin. First stage the cover itself with the oil pump and timing chains and the 2 crank gear/sprockets because there is no way to reach any of this once the cover goes on so it has to be in place and you have to try to get the gears on the crank and timing chain drive onto its studs as you go (I drilled hole in the front of the cover to allow access to the timing chain drive nuts so they can be installed last).


Then the oil chain tensioner goes on the block. It has a lock screw so to lock it retracted, get the cover on to about 1/4" gap then slide a lock screwdriver in and try to release it without actually seeing it.


And it all has to be covered with sealant because there is are a couple timing chain idler shafts that need to be seals but they cross the block/head line so you need to work fast before the sealant sets up


And if all goes well you end up with a cover in place that won't leak....if it all went well.


Next up is indicate the cams in., then covers, intake, clutch and bellhousing...it should be an engine by next weekend.

I love it when I log on and I am two pages behind. Morning coffee and catching up.
I have timed cams with the lash set and just deducted the lash. If i have it set @ .24, I just check the timing @.26. That makes .50. I have done this and then set the lash to zero and rechecked the timing. It was spot on, so it works.
So with your lash @.011 & .007, cam timing is checked at .039 & .043 and will be spot on.

Can't wait to hear it run properly.

_________________
Wade Williams
Master Ferrari Tech
Restoration Tech
Engine Machinist
Fabricator
Racecar Driver

With the software its maybe even easier....it gives you the valve timing accounting for lash, that is the the row with the pointer shows and you can see its less duration than the row above which is the cam(o lash) timing


Woke up early and rather than waste the time before work sitting I timed bank 1

first I confirmed my TDC setting on the degree wheel with a high tech welding rod extension for the dial indicator. Actual TDC is pretty hard to read directly so I read the indicator at +/- 15 degrees and make sure they are the same, TDC is exactly in the middle.



I did exhaust first, if you look close you can see my pencil marks on the wheel that way I'm not trying to remember anything. I got it within 1 degree which is about the best I can do...the cam moves about 0.6 degree each pin hole, the crank 1.2.



Then did intake, I got it almost perfect. then a brought the engine to TDC to see were my original marks were...they were correct
Intake


Exhaust

I'm felling pretty confident.....just ordered oil, filters, coolant and a scale because I'm really curious what it weighs, hopefully under the 1100lbs the scale reads

I timed bank 2 then rolled back to #1 TDC to remark them....the marks are perfect which caused more staring in disbelief. Finally I arrived at I did the clay test pretty wrong. I put it together correctly but because of the clay I just turned it and disassembled and then wondered what the hell had gone wrong. For a real assembly its align the marks, rotate, realign the marks cam by cam until they all come to the mark with the chain under tension and all the lash out of the system. I didn't do that for the clay because once I turn it the clay is smashed. Not sure how I convince myself they were as wrong as I thought I was seeing them....but the marks are right and the bank 2 exhaust cam clay looked as bad as it did because its last on the chain which does stretch under load and would have had the most slack to begin with I guess..... so it l so on to other things.

So you did the clay test with no tensioner?

_________________
Wade Williams
Master Ferrari Tech
Restoration Tech
Engine Machinist
Fabricator
Racecar Driver

No, No Tensioner in place but there is a lot of rolling friction up in the valve train and a lot of lash in the timing chain drive.....20 degrees probably? And there is chain stretch..5-10 degrees? Its a very unsettling process honestly

When you get a few miles on it, pull it back out to re-check cam timing.

Sadly, at this point I'll be pretty surprise to actually get a few miles before it comes back out

I started cleaning up the cam covers last night...I just don't have the heart to paint over the pretty aluminum. I'll paint the air box red when I get that built.

This whole cam thing still has me confused about what I thought I was seeing...I rechecked lash this morning and its right where I set it but I will probably also do a quick leak-down as a sanity check before I go any farther.