Timing marks; look good BUT.......opinions

The alignment looks about the same as when I degreed my 308QV. Looks like you're good to go.

 

Leave it alone. If the car ran well before there is no need to bother with degreeing the cams, especially if you are not 100% confident in what you are doing.

I did degree mine, found two of the cams were slightly off, adjusted them, and when I finally finished and got it running again felt...... absolutely nothing. Still a fun exercise, but unless they are way off it's not something you will notice seat of the pants.

 

Degree wheel/dial gage! If Brian where here he would say....(read my signature below)

 

1, 2 and 4 look pretty good (assuming that the factory marks are correct). But 3 looks off enough to think about resetting it. Remember, the width of the timing mark itself is about 3*+/-, IIRC, so what you've got there could be off by 6* or more. The timing gear pins have multiple combinations, so you can adjust the cam by as little as 1 or 2* with the cam pins, again IIRC. So if you wanted, you could get that cam much closer to the factory marks with a little trial and error.

The problem with that, of course, is that if the cam slips while adjusting, or if the other cam on that bank moves, you will be doing a full cam timing job on that bank. If the car was running well before you opened it up, and everything is exactly where it was when you opened it up, apply a corollary of Murphy's Law -- if it ain't broke, don't fix it. Hopefully, you checked the location of the marks before you started, relative to TDC, so you can confirm that everything went back as they were supposed to. When you start it up, you'll have a good idea if it's correct or not.

 

I agree with Carl, dial indicator and degree wheel--if you want it done correctly.

 

Do you want it "close enough" or spot on as the factory intended? The engine could run OK, or great. In that it sure looks like you've put a lot of effort into this job, why not pass on mediocrity and dial her in.

Here's the right way.
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Those are assembly marks ..... NOT timing marks.


Search and find RifleDriver's thread with pics on how far off those marks can be.

 

FastRadio shows the way.



Degree the cams properly or accept the factory's half-assed effort.

Fatbillybob gives one of the best tutorials on the subject.


I am degreeing my cams shortly after I replace the screwed up shims and replace the cam gears with single piece aluminum gears.




And BTW, ALL 4 of my cam assembly marks line up PERFECTLY even with the flywheel mark.

It is 100% perfect ..... on the OUTSIDE.


I KNOW; however, with 99% degree of accuracy, it is wrong on the INSIDE.

 

In order to phase the cams, you have to be reasonably comfortable that the pistons won't hit the valves while turning the crank.

The assembly marks are the first pass of the process; a starting point.

Once you have the cams set to the assembly marks, you can proceed with dialing in each of the cams with a degree wheel and get all four right on the money. Don't pay attention to the marks after that...

 

Correct.


I have to admit I have read alot about doing this but never have done it.

Can't wait to give it a go !!!!!!!


Can't wait to become "EXPERIENCE Educated" instead of just "book smart."

 

Seriously, Welcome to the joys of Italian car ownership.


I stand right with you with a "deer in the headlights look" much of the time too.

 

just went through this myself. it took me nearly two weeks until i was satified with things. there will come a point where you realize it just can't be any closer. the car was built by humans; accept it.

 

If you're going to loose sleep about this, then just bite the bullet and let the timing exercise begin. I bet I spent at least 16 hours the first time I did a cam timing. Performed every step at least 3 times. Take a deep breath and have fun.

 

THAT is 99% of the battle.

If you are not having FUN, STOP .... and take it to a PRO.

 

Given that the timing pins on the pulley are capable of smaller than 1 degree of adjustment;
Do you really think you can read the timing mark to that kind of accuracy?

My guess is that you could be off by 3+ degrees and you would never know.

 

Dial gauge and timing disc is the only way to go...
Chris

 

Everyone has an opinion on this, but many are based on what people have read (probably elsewhere on this board).

I would ask that everyone who is saying that he should degree the cams and has done this job himself on his own car please raise their hand.

 

Good post. As it happens I suspect some have but not by any means all!

 

Yup...

Many hundreds of times...(Here's another recent QV engine job having her cams dialed in)
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Great thread.

So does degree the cams mean you pick up like maybe 20hp? Isn't that like going from having a REALLY, REALLY slow 30-year old car to a REALLY slow car?

And, forgive my ignorance, but this work seems concentrated on one piston and its cam lobes. If there is slop in the system, so to speak, might there be irregularities in the cam lobes for the other three pistons? That is, might you have everything totally perfect for the #1 or #5 piston but half-assed (to quote Rifledriver ) for the other three cylinders?

 

Of the many you have done, how many did you find to be significantly in error relative to the factory marks? And of that subset, were any off enough that correcting the timing could actually be felt?

I only know what I have read (i.e. that QV motors are not overly sensitive to cam timing), and my own experience with my car which seems to support that. However, that is only one data point so I am genuinely curious to know what others have actually experienced.

I can certainly understand wanting to have everything "just right", which is why I elected to degree my cams (with the excellent help of this board and its contributors). Nothing wrong with that. That said, I hate to see someone pushed into performing a somewhat technically involved procedure that may not have any tangible benefit but carries a significant amount of risk if not done correctly.