Starting to understand why building engines may be best left to the professional

[Yellow Truck]

Brent, the dots are lined up, or more specifically, the gear teeth they are aligned with. That picture mostly showed my inexperience, it clearly shows the cam gear is advanced relative to the crank.

I just took it back to the 0 keyway and measured it again. It should have been the same as before I dismantled everything, but I am showing the intake open 0.050 at 3 degrees instead of 8 and closed 0.050 at 52 degrees ABDC.

I am now thinking about what to do. Clearly these measurements are different than before I took it apart. I think I should just do the 4 degree advance and put it back together.

[Yellow Truck]

For the avoidance of mistakes by me...IMG_3354 by Fred Snoyd, on Flickr

[blykins]

Ok, I was just making sure that wasn't the issue. 

I wouldn't make any rash changes.  You have to get to a point where you're confident with your measurements and can repeat them.

[Yellow Truck]

I'm getting consistent results, they just are not what I expected. I just went back and moved the indicator, re-zeroed it, and ran the sequence again. 0.050 open at 3 BTDC and 0.050 closed at 50 ABDC, max lift is .337, so the readings are consistent. What is different is I'm using a pushrod and a conical tip to keep it centered and lined up.

The pushrod gets a better seat in the lifter.
IMG_3407 by Fred Snoyd, on Flickr

[blykins]

So you're showing 6 degrees retarded from where it should be.  Cam card says it should open 9 degrees BTDC and it's opening at 3.

What happens if you put the crank gear on A6?

[Yellow Truck]

Haven't tried 6 yet, took a break for dinner. I'll do that next.

BTW, when I had it on the A4 keyway I was getting more or less what the card called for - 8 BTDC and 46 ABDC is only one degree off the card.

[blykins]

BTW, this is the essence of engine building.  Take measurements, be comfortable with them, then make it do what you want it to do.

Its rare but I've seen more than a handful of combinations where the tolerances just stacked up.  Crank may have been out, cam may have been ground wrong, timing set may have been off.

I have put more than one crank gear on in an 8 deg advanced or 8 deg retarded keyway to make it right.

[blykins]

Then if you're comfortable with your measurements and the A4 keyway made it right, then you can put it there.

I have missed a lot of the dialogue between you and Ross but if the math shows that it would work, I'd run that cam way ahead....like on a 104-106 ICL.

[Barry_R]

Put that thing in the A6 position and recheck your measurements.  If you notice, the cam card is spec'd for events when installed at 108 ICL.  I bet everything just "comes in" at A6 or A4.  After you get done verifying the open and close event you can go ahead and recheck using the centerline method.  Even though some folks might say it won't work with an assymetrical lobe I bet it comes in right where it's supposed to with the open and close events right.  I have degreed that cam a couple of times...

[My427stang]

Could this thing be going funky from the hyd lifter? 

It'd be nice if there was a way to reach down and push off the body

[blykins]

If he's just pushing a dial indicator, I don't think it would compress the lifter. 

His lobe lift measurements also match cam card.

[Yellow Truck]

Done for today - and not much less confused.

A4 shows open at 8, close at 47, and peak of 0.338 (note this is slightly higher than the cam card calls for but I am getting it consistently with each test) starting at 110 and continuing to 116.

A6 shows open at 10, close at 45, and peak lift starting at 108.

The cam card is right between A4 and A6. I check TDC before and after measuring for each position with the piston stop.

I won't get back at it until tomorrow afternoon, at which time I need to make a decision and button it up because on Tuesday it rains (hooray, forest fires are out of hand) and the truck is outside.

[comet2]

looks like a6 is your straight up!  goes to show how important it is to check your parts ! if this happened to me when i built my motor i would have been screwed there was no fe forum i could picture myself in the garage staring at the wall wondering why i didnt do an ls motor. NOT!!!! anyway good luck! that thing will be a bear when your done !

[blykins]

You can button it up and know that you're pretty stinkin close to the card or you can stick it on an a8 keyway and advance it a little more. 

Comet, "straight up" actually means that the ICL equals the LSA.  He isn't straight up right now, he's actually around 2 degrees advanced.  I'm only stating that because a lot of guys call putting the cam in the way it's ground "putting it in straight up" and although that term is thrown around a lot, it's technically incorrect.

[Barry_R]

looks like a6 is your straight up!  goes to show how important it is to check your parts ! if this happened to me when i built my motor i would have been screwed there was no fe forum i could picture myself in the garage staring at the wall wondering why i didnt do an ls motor. NOT!!!! anyway good luck! that thing will be a bear when your done !

A6 it is.  I bet it runs far better.  Timing chains stretch in service so it will retard a bit over time.