Timing Marks on Camshafts ?

yes all 4 marks should line up. don't trust the flywheel mark it's vague, use a dial gauge or stop to get cyl#1 at TDC. from there line up your cams. sounds easy but the process of removing the cam bolts and pins can be a bit of a pain. you'll need to get new seals of course, and don't forget the ones on the cam bolts. the cam bolt washer also has an index slot to fit over the pin, you'll see when you flip the washer over.

after it's all set up and the belts are on, rotate the engine thru a couple cycles and check that it still lines up.

I also paint a line on the flywheel for the exact TDC.

 

http://www.ferrarichat.com/forum/showthread.php?t=148604

http://www.ferrarichat.com/forum/showthread.php?t=148917

Different Ferrari same rules apply. Your timing is most likely off unless the marks are off from the factory. You need to degree the engine to find out.

 

When I did the cam timing on my '78 308 GTS two years ago, we found that the factory timing marks were very close to being dead on. All were within the l l on the cam caps. But remember, those marks are at least 3 degrees or more wide. The only way to tell for sure that you are dead on is to degree that cams.

IMHO, as a starting point, bring the engine to TDC on the intake stroke on #1 rear bank. If all 4 cams are not within the l l marks on the cam caps, something may be wrong. As to TDC, don't rely on the timing mark on your flywheel. You should check it with a degree wheel and piston stop. I was lucky, mine was dead on. Some are off a little bit. Once you have the flywheel/engine at TDC, intake on #1, align all the factory cam marks with the cam caps. This may take a lot of time, as playing with the cams and pins can be a real PITA getting them right. Then you can go ahead and degree the cams, and you'll likely find that the factory marks are not far off. But remember, if it's off by the width of the l l on the cap and the l l on the cam itself, that is at least 6 degrees of cam timing off. And also remember that these are high interference engines. So go very easy when turning the engine over by hand, and stop immediately if anything hits.

 

Good advice all. I would add that both my 77 motors had the flywheel register off so far I had to reslot the index plate to move over far enough. IIRC Big Tex had the same issue on one of his. When your flywheel marks are off 3 or 4 degrees before you even start, it can only go downhill. And when you consider the euro cars have 15 more HP (supposedly) and the only real difference between the two engines is 4 degrees different valve timing, its obviously worth taking the time to set it up. I also found that while most of my cams index marks are (somewhat) close, one is off about 20 crankshaft degrees. If any of you turned my flywheel to TDC on #1, you wouldnt find one cam mark centered, and the one is off nearly 1/8th inch! You'll never know what you have for sure without using a degree wheel. Once you have it right you wouldnt really have to do it again if you reindexed all your marks or make notes, pictures etc., but without knowledge beforehand your really just shooting in the dark using thier marks. It will run just fine on the factory marks, but if you take the time to do it right, you wont be sorry.

I have the hardest time setting the front cams, my tired old body just dont want to contort itself so good anymore. You have to line up pin holes while keeping the cam where you want it, and to get it perfect takes a bit of on and off, on and off with the pulley, and turning the pulley under the belt, slipping it back on the cam, repinning it, and rolling the engine twice to check your work. Its a bit frustrating trying to keep it in your head that the crank turns opposite of the cams, so advance and retard works backwards from what your foggy brain is telling you. So you think you advanced only to find you went the wrong way (oops) and now you do it again. It is really easy to say the hell with it and just use the marks, but when you see all four cam marks are off a bit or so, yet correct on the wheel, you KNOW it was worth the effort. And when you run it and you FEEL and HEAR the change, its truly satisfying. Its smoother, crisper, and snappier. And having the flywheel marks correct gets your ignition more correct, its really a win win. And I have noticed over the years on engines with adjustable valve clearance, that having them all as equal as possible also adds smoothness, regardless whether your running them loose or tight. Seems you can spend days tuning one of these 308's, syncing the ignition between banks and the setting the carbs, but they do respond well if you have the patience. BTW, I blast the cam bolts on and off with an impact, dont tell anyone.

 

Not sure about my flywheel marks, but JRV did set my cams to the European spec and it was a noticable difference, as you say.....

That car is about due for belts and bearings so we'll see how it comes back from that operation.....

 

Paul,
I agree, it's a PITA. Thank goodness it doesn't have to be done all that often!

You need a pair of my 2V cam locks. Once you have the cams dialed in, the cam locks will keep the cams in place while you're fighting with the pulleys. You then loosen them for the engine rotation & re-tighten them as needed.

Another thing that really helps is to glue a strip of old belt to a strip of 1" wide 1/8" steel or Al that's long enough to go across both cam gears on a bank. It ensures you have the cams timed relative to each other. Once that's done the belt will usually go right on.