Hello gents, wich type of degree wheel is ok for the cams set up of 308 gts carbs? And you have the Specs? Thanks in advice Inviato dal mio iPhone utilizzando FerrariChat
I printed one from the internet and backed it with card stock. Tuns out the magic isn't in the degree wheel. Bigger is easier to read. I think I printed it for the biggest size on A3/letter paper.
The factory marked the flywheel so you wouldn't need to buy one. The only reason I have a few degree wheels is I use them frequently. Many Ferraris have been timed quite successfully from the flywheel markings. Ferrari devised their timing method so you didn't need special tools and it works great.
Are we talking cam or ignition timing??? I agree with flywheel marks for ignition timing. I would be interested in the method used to time the cams from the flywheel marks. Thank you.....
He already posted it a few months back. Essentially, you adjust the valve clearance on the one valve to 0.5mm Turn the flywheel until the proper marking shows up Try to turn the valve shim / bucket with a pick. If the valve is just beginning to open, you should go from spinning freely to not at all If that valve is just beginning to close, you should go from not spinning at all to just spinning If that does not happen, you adjust the camshafts until it does.
Ok .... my 308GTSI flywheel only has markings PM 1-4 & 5-8 and full advance for both banks. I’m not fully understanding the concept. Sorry. I presume setting the clearance to 0.5 on a certain banks cylinder(which cylinder) and then turning to which mark? Thank you for helping me with this concept.
I don't have your user manual here so I cannot tell. If you have a workshop manual, find the valve timing diagram for your car and post it. We can explain it then. I personally attach a degree wheel to the front pulley because it is so much easier to read it for me. And I am used to doing it with 348, 355, 360 engines.
Here is Brian's post: Set the # intake and exhaust valve [on Cyl 1 and 5] to 1/2mm. Slowly turn motor to intake [valve] opening mark on flywheel. With a pocket screw driver or similar device put a small amount of rotating pressure on the notch in the top edge of the cam follower just when it stops spinning free you should be at the timing mark. On the exhaust side it should go from locked in place to free to spin [at the point where the exhaust valve just begins to close]. Then you are done.
Note that your 2V engine is not extremely sensitive to exact valve timing. On your car, lining up the assembly marks is likely good enough. I still encourage you to go through the exercise as a learning opportunity for other cars you may own in the future.
Thank you ... this makes perfect sense, only need to know what mark to look for. The 308 flywheel only has 4 marks. So which of the 4 marks is the 308 mechanic to look for? Not sure the manual shows the process for 308GTSI. I would really like to use it next time. Thank you for any support.
Correctly timing 308 camshafts is a procedure that has completely eluded me, and I feel rather frustrated and stupid not knowing how it's done. Most things I've been able to figure out from the WSM and reading Fchat archives, but this one - everything I've tried to read seems to omit a step (or, assume one is already familiar with the overall technique.) So I suppose the next step is to ask a stupid question: How do you adjust the camshafts? I mean - literally, how is it done? I assume the belts are still attached during the procedure? And if YES, then... what, you loosen the nuts so that they rotate freely from the gear? Do you loosen ALL 4 gears, or one-by-one, or...what? I know how to remove and install the shafts, to hit the installation marks. But am aware that's not correctly timing anything. I'd like to do it the right way.
From an old post, and specific to a 308QV: According to the QV/328 service manual the 328 flywheel is marked the same as the 308s. Note that the flywheels have other marks in addition to PM1-4. Such marks as PM5-8, and AA - Inlet valves Open, CS - Exhaust valves close to aid in checking valve clearancd (0.5mm). So, my guess is you should look for AA and CS markings on your flywheel.
The adjustment is as follows: IF you need to adjust, then 1. Loosen the cam sprocket bolt a few turns so that it no longer locks the sprocket tight to the cam shaft 2. Remove the indexing 6mm pin from the pulley / camshaft combo 3.a. IF the crankshaft is already in the correct position, then you turn the cam shaft until the valve is in the correct position 3.b. IF the cam shaft is in the correct position then you turn the crankshaft to its correct position 4. Look for a hole that is aligned between the sprocket and the cam shaft where the 6mm index pin will fit 5. Fit the pin in, change the oring, tighten the bolt, and you are supposedly done. Caveats: step 2 can be very hard to do if the pin has not been out in 20 years. Just happened to me. I destroyed a pair of pliers for that, as well as a few pins. step 3 can be hard. How do you turn the camshaft if there is no flat spot to accommodate a wrench? You will have to figure it out. step 4 can also be very hard. The cam has 3 alignment holes. The sprocket has 5 alignment holes. Finding a pair of holes that match up is pretty hard. Perfection is not going to happen here. If you cannot find a perfect matched pair of holes, you are supposed to remove the cam sprocket while the belt is under tension and move the sprocket one tooth over, then you will have a better matched pair of holes. Good luck with that. step 5 can be hard unless you have an air impact gun So yes, the instructions and the cam timing diagrams are written for people who have been through this with some experience. It is not meant for beginners.
Thanks for all the typing. Not sure I'm ready to attempt it, but at least I understand the basic mechanical approach now. I've set timing on other types of engines, but this one - a completely different situation to me. And I know enough to know what I didn't know, as it were.
Don't think that any of the 2-valve V8s got the extra valve timing marks on the flywheel. Know that 328 has them, but unsure about the 308QV (although my guess would be that 308QV does not have them as the 308QV/328WSM only specifies using a goniometer for the 308QV with no mention of the AA and CS marks; whereas, for the 328 engine it specifically mentions the AA and CS marks on the flywheel).
Thank you everyone for the interesting differences amongst the 308/328 flywheels. That said the 308GTSI flywheel doesn’t have the extra ‘cam timing’ marks. Sooo stick to the degree wheel on those flywheels....
You are supposed to put the valve shims (that were in there before this) back in their respective places. Then you are done.
I bought mine from dinoparts but subsequently I believe derekw had some made for half the price. You should check if he has any left. Sent from my iPhone using FerrariChat
Is the flywheel meant to be on the PM5-8 mark, when I'm setting the #5 valves to the 0.5 clearance? Or are all 4 cams set to .05 clearance using the PM1-4 mark?
Oh man, stop for a bit. All valve adjustment for all cylinders is done at TDC for that specific cylinder. When you do cam timing for Cyl1, you start with PM1-4. When you do cam timing for Cyl5, you start with PM5-8.