Cam timing Alignment Question - See Photos

dont bother Dave Helms right now - he is setting the valve timing on my 308 as we speak..............yes, degreeing the camshafts and adjusted my TDC on the flywheel (now the pointer will point to tru TDC)....shhhhhhhhh - he came up with some juicy numbers for the intake and exhaust timing.......

 

Too late, I already did. Your car is going to run for ***** now. Sorry.

 

Doesnt anyone here work?? I think I will follow the trend, lay the tools back down on John's car and throw my feet up on the desk for the rest of the day. Tried that........ the Boss (read, wife) in the office threatened to throw me out on my ear, and Niki yelled "hey Deadbeat help me torque John's axels". Hows that for respect? Torque them yourself, Shrimp!
Brian is spot on with what he says. Funny story about watching the factory guys cam time 360 engines when we were all over the pond getting "Trained" on these. I will chime in tonight when the mob is more civilized.
I would venture to guess that the marks on the cams might even have been put there prior to the cams being ground. They might well have indexed them in the cam grinder by these marks when they were still a rough forging.
VERY rare when all 4 marks all line up when all is done properly. PITA to degree these when the engine is in the car but often a nice change in performance if it was off before the belt change. Sure cant tell if it was off by the marks but remember "Even a blind Sqirrel finds a nut now and then" , they MIGHT be spot on.
Dave

 

If valve covers are off, I check the referance marks and if they are in the goal posts, just change the belts.

if covers are on, and no problem is suspected (after test drive and nearly 20 years of Ferrari engine "feel"), I just change the belts.

I only degree cams on engine rebuilds, or if specifically requested to, or if a problem is suspected.

Finally, we need to remember that cam timing, within a pretty big window, only really effects the rpm at which peak power/torque figures are achieved, not the actual value.

people that "feel" a difference after degreeing basically "ok" cam timing, may just be noticing that the car has better torque around town, but if the car were pushed hard for a long period, may actually measure a small drop in top end power.

As a small example of this, I have just built another 360C speciale engine, with deleted exhaust variators. I re-use std exhust cams, but time them WAY retarded from stock setting. Which makes peak power achieved at higher rpm.

On a std road Ferrari, a retarded exhaust cam gives good top end power too, but inlet must be kept closer to stock setting.

 

people that "feel" a difference after degreeing basically "ok" cam timing, may just be noticing that the car has better torque around town

Isnt that what this is all about?

Most of the track savy drivers are looking for torque unless there are special circumstances that require retarded cam timing for a certain track. The cam timing on PRO race cars is set differant for each and every track. The 250 GTO (3223GT, the first) that I used to maintain had 4 completely differant settings for various tracks around the world and the factory and NART guys noted all of these.
In the spec class race cars where the cam timing could not be changed I checked the cam timing on a dozen belts and saved that one belt that was stretched a great deal just for Road America and the likes.
The IMSA 348 that I built the engine on has a 3 hr life span due to belt stretch and resulting cam timing change. Great sprint engine but nothing else.
NO one driving around town and weekend spirited driving can REALLY feel horsepower, they feel torque and if we can improve that we have done our job well.
When doing the PDI's at the dealership there were 3 classes of cars, the real dogs, the norm cars, and the real rockets. The only differances between them all was cam timing and seat of the pants it was huge when compared back to back. The window that the factory uses as acceptable is very large. The trainer we had at the factory on the 360's preached long and hard about perfection in this area before they took us out to the engine build area to show us the masters doing it first hand.
Watching the guys at the factory set the timing I noticed they set the pointer on the degree wheel with a plastic hammer after watching a dial indicator on the piston come up to what they thought was TDC, not once taking into account the dwell of the piston at the top of the stroke. No before and after TDC checks to find true TDC was ever done. The cam lobes were hit with the plastic hammer to change the cam timing and all was locked down and the training director said "and thats how its done". There were a few of us in the class that have been setting cam timing on race cars for 30+ yrs that knew this was not correct and I told the trainer that it wasnt. He challanged us to retime the engine and he would show us that all was well. After doing this and proving the timing was off by a substancial amount the 2 guys timing that engine were wisked away and our tour was quickly moved along to a differant area in the factory. Next problem is the "tour" was then off schedual and we stumbled across and a car being test assembled on the line and all hell broke loose. Car covers were being thrown on the car and folks were running all over yelling because we had seen something we were not supposed to. Brian will have to chime in here because I do not remember what car that was, but it might have been the Enzo.
There are a number of engines that were in the corner of the Dyno room that were tagged to go back to the engine room for re-adjustment because they failed to produce the power they were supposed to and I would bet that the majority were due to cam timing being off.
We had a customer at the dealership that had a 99 360 that everyone at FNA knew was HEAVILY tracked with slicks and F40 brakes I installed that was a rocket. The ownner decided to replace it after a number of years with a new car so he could have a "race car with a factory warrenty" and the new 360 (I think it was a 00) was a real dog. The customer being friends with the FNA tech rep, raised a bit of hell and the tech rep authorized me to find the problem and document it with dyno tests. First thing that was found was the new pre cats that the factory had stuffed in the headers and didnt bother to tell any of the techs about (talk about stuffing a potato in the tail pipe!). At the time the factorys stance on cam timing a 360 was that it couldnt be done with the engine in the car. I came up with a method of doing it with the engine in place and reset it to what it should be. Wish I still had the dyno sheets as I do not remember the numbers but it was in the high 20's to low 30's as far as HP increase and a much nicer torque curve than the factory cam timing. Of course after spending all that time on the engine with all of the dyno tests, cam timing resetting and all, FNA declined the claim to the dealer.
Facts:
Factory cam timing after the late 60's is a ball park affair. Fiat decided that it was time tio make a profit and if it ran smooth and passed emissions it was good to go.
Any double digit torque increases can be felt seat of the pants and are worth going after. Thousands of dollars are spent bolting on performance parts that wish to gain increases of this level.
Component wear dictates that even a cam timed engine should be re timed at least every 2 or 3 belt changes to keep everything at its peak.
As said in my earlier post, everything might be spot on as it is, as some of the cars came to us as rockets.
Getting all 4 cams doing the same thing at the same time and the right time can only be accomplished with a degree wheel, dial indicators and time consuming focused effort. Two degrees off from bank to bank will have 1 bank making power and the other going along for the ride. Folks bought these cars because of the dream of the performance, these cars are not transportation.
Dave

 

Phil- thank you. I see your proceedure a quite a bit different than some of the others.

Dave-
Thanks for the reply- very interesting.

I'm still curious about the "time consuming focused effort" process you mentioned. Would you mind talking about this a little more?

Here is how Verell and I timed my 308 QV when we had the engine out (flywheel removed for engine stand install):

my memory may be a little rusty- so proceed with caution!


1. mounted temporary degree wheel to damper- same diameter as damper- see photo
2. mounted temp pointer to alt mount- see photo
3. reinstalled cams with old belt/new tensioner bearings using cam/cap timing marks to get it close.
4. mounted long dial indicator into piston 1- located TDC and then marked it on degree wheel- then removed dial indicator
5. aligned exactly (if possible) with cam marks and locked down cams with a strip of business card under two caps per cam- caps just snugged down on paper
6. released tensioner
7. removed old belt
8. loosen locked cams caps sligtly to allow perfect alignment with cam cap marks- then locked down cams again
9. installed new belts- using temporary dowels(drill bits the same diameter as dowels- easier to relocate as needed during alignment) in pullies
10. removed paper locks and torqued down cam caps to spec
11. lock tensioner at it's spring applied maximum tension
12. checked marks after a couple of engine rotations- still needed a little adjustment with dowels to get marks on caps perfect.
13. installed correct dowels- torqued down pullies
14. final few rotations to verify cam marks agreeing with degree wheel TDC mark

that's it- I think? Verell- did I miss anything? I'm sure I did forget something- this was my first time doing 308 belts. The basics are there, but I'm sure Verell can revise and add specifics.

So- in your opinion, this was done inaccurately because we counted on the four cam cap timing marks to be correct?

I would have no problem taking whatever time is required to cam time my engine next time the belts and cams come off- I just don't know the proceedure. How do you know what degree the cams are in at any given time? Do you check every lobe? Or, just check each cam since there is nothing can be done about same-cam lobes not in sync with each other?

Maybe this is beyond my ability?

I'm sorry if these are dumb questions- I'm (and others) just trying to learn as much as we can about these cars.

thanks again in advance-
jwise
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It doesn't seem to make sense to me to go to the trouble of re-clocking the the cam pulleys by using the cast mark on the cam bearing cap, if you're going to that much work, why not measure the valve lift?

Has anyone degreed their cams (measuring valve lift), confirmed TDC, and then taken a picture of the cam & bearing timing mark alignment?

 

Tom-

That's a great idea. Please do.

Larry/Tom- would either (or both!) of you please explain how to degree the cams, and then what exactly to do with that information?

Thanks again-
jwise

 

Is this the basic process?

http://www.ridgenet.net/~biesiade/camdegree.htm

 

Umm, John, You've got steps 3 & 4 reversed, cams don't go in until the engine is on TDC.

We checked TDC 2 ways:
0) With piston stops in #1 cyl. spark plug hole. Rotating engine up against stop & reading timing wheel in both CW & CCW directions & marking TDC in the middle.
1) Then again doing the same with the dial indicator.
Got same TDC with both methods.

I'm going to go out on a limb & describe how I was taught to time cams by an old time Jag. racing mechanic, I'm sure I'll be sharply corrected if I've got it wrong:

You check using 1 lobe/cam.
You adjust shim thickness on that lobe to get as close to 0.5 mm cam-shim clearance as you can. Then the method is essentially the same as locating TDC, except that you can only rotate the engine CW in order to keep the belt tension consistent.

You put a dial indicator on the shim, rotate the engine CW, & note the degree wheel readings where the dial indicator moves a small fixed amount (valve starts to open), and returns down to the reading you used to establish opening (valve is closed). The lobe center is 1/2 way between the 2 readings. Best to do this a couple of times to make sure you've got good readings. This will work with worn cams.

Another trick for locating the open & close points is to pressurize the cylinder with air regulated down to a few PSI. At the open & close points, you can hear the air hissing thru the valve opening. Works best if you have the intake & exh manifolds off. Suspect you could use a leak-down tester to do this as well.

Here's how I interpret the QV WSM procedure:
The WSM method is to use the open & close points & assume they match the WSM cam timing diagram. This works IF 1) The cams aren't worn, 2) The cam-shim clearance is EXACTLY 0.5mm. Otherwise the actual open duration will be slightly longer or shorter than the WSM values.

 

Looks like you posted the process link while I was writing...

Looks like the same procedure.

 

Umm, John,
Wish you hadn't posted that I use it. It's in the category of "don't do this at home"...

I sometimes do, but don't recommend it for someone w/o a lot of mechanical experience & a gentle touch. That's why I started making the cam locks which can be safely used by anyone. If you recall, I made those prototype QV cam locks for use later in this project.

Theres' risk of bending the cap if it is overtightened, and/or especially if someone uses something thicker than a folded $bill or at most a business card (like a matchbook cover).

 

Sorry- I didn't realize that. I'm lucky- I had you as a teacher to make sure I didn't really mess something up.

I assumed (incorrectly) that the external cam lock you made that we used on my car would only be used if the cam covers were staying in place.

 

I know this was talked about in various threads, can't find who's working ont eh prototype and if they are taking orders yet or if there is a universal tool out there that has worked..just got my lift and I am planning some winter projects...and sorting out what I need to do what in order to prioritize and figure out what jobs will be bigger than others and desperately trying to avoid "shipsright" disease or else the car will never get back on the road for spring. Couldn't manage w/o the tech contributrs here..you guys are very generous to share.

 

NYCFERRARIS,
No one has reported success with a 'universal tool', & I doubt that there's one out there that can be used to hold the cams while changing the cam-cam gear alignment. All the universal ones I've seen hold the cam gears for a belt change, but that's it. None of them work with a 3x8 because of the outer flange on 1 gear.

The only Ferrari cam lock in production right now is my 2V design.

For pix of it in use, ordering info, etc. see this thread:

Cam Gear Locking Tool for quick belt changes
http://ferrarichat.com/forum/showthread.php?t=40071&page=2&highlight=cam+lock

BTW, Based on experience building quite a few of these, price has increased slightly since ordering info in that thread was posted.

I don't have a 4V tool design I'm happy with yet. I have a design that locks the cam gears, but as JWise points out, it can't be used to hold the cams while you're changing the cam-cam gear timing.

BTW, Suggest you update your profile, at least with your model, it'll help get relevant responses.

 

just planning on the belt change only this time around...might change my mind when I get into it though...these timing threads both boost and diminish my confidence to do the cam timing...I think it is really pretty straight foward but risk for a first timer might be costly. So..what universal tool to simply hold the gears from jumping for a belt change...on the QV? I will get to the profile, wasn't aware of that missing info since the crash.

 

Sorry, your post & my edit crossed. No univ. tool works for 3x8s that I'm aware of.

Depending on your timing, I'll loan you my prototype tool, just don't laugh at how crude it is, I hacked it out of nylon block w/a bandsaw in about 15 minuites when we were doing the JWise timing drive service. There's pix of it in that thread.

 

I am not quite sure I am aware what you are getting at by measuring the lift.
There are several ways to measure timing and some of them include lift but I would need much more info.

 

I'm saying degree all 4 cams using degree wheel on crank and dial gauges on buckets @ prescribed lift, pinning cam sprockets/pulleys in this new and exact position.

Then put crankshaft @ exact TDC and see how close the cam mark & cam bearing marks are. (to see how accurate the factory marks are compared to exact cam timing)

 

Different motors have different sensitivities to cam timing. In general the higher performance the more sensitive. As I said before, of the Ferrari motors the 2 valve v8's especially during the heavy smog years prior to the 4V's tend to be the least sensitive. We also dont really care so much about peak power. As Phil so accurately pointed out we can juggle cams around a bit and it really won't change much, certainly not enough to notice. Who really cares about that anyway. Peak power is only achieved at or very near redline anyway and how much time are we driving there? What we are concerned with is torque, throttle response, a good idle, plugs that don't foul, clean crisp response when we are rolling the throttle off idle and to keep those ***ing check engine and slow down lights off. Those items cover about 90% or more of our driving. Ray Charles (RIP) could have tuned a motor to give good peak power, it is all the rest that is harder to achieve and is what we notice and provides a car that is pleasant to drive.

The last 2 items on the list are things that are completely lost on our friends from outside the US. The parameters for proper operation are set very very much closer on our cars than any where else in the world thanks to Uncle Sam. We hear stories incessantly about check engine lights and slow down lights, doesn't that sound familiar? Lots of them are caused by cam timing issues and on a US car it does not take much. If you see an o2 sensor out of range error it is about 50% of the time a cam timing issue but it is much easier to throw O2's at the car and kick it out the door when warranty or a recently performed service is in the picture.

It is true that once everything is properly set you can do belt changes without going through this every time. The key is it needs to be set right once. Also as Dave and Phil pointed THAT one time is not always by the factory. If you have a Ferrari of any age and are maintaining it yourself take the time to do it right the next belt change, the car will pay you back for your trouble.

I will explain how to do it for the valve shim cars and if wanted how to do it on the hydraulic cars too if any one is interested but will not do it all today.



For starters I would want a much larger degree wheel than what you have here. The factory wheel is about 11 inches across but the one I really like to use is a Moroso Pro Wheel and is 18 inches across. The bigger the better. it is no accident that the ones pros use are big. It is easier and more accurate. It's also perfectly OK to use the marks on the flywheel, thats what they are there for. The first thing you need to do is to find TDC. Lots of ways to do it but building a positive stop device that screws into the spark plug hole and is adjustable so that the piston can be stopped or blocked from further upward travel just a few degrees from TDC is best. Turn the motor both ways until it stops and TDC is halfway between the two points. You can at that time ck and correct the pointer. You can also use a dial indicator but it is nowhere near as fool proof.

I'll go into more later. It's really not that hard and Ferrari devised a way that is simple and does not require lots of expensive tools. I often do it a different way because of my resources and will go into that for the people that are equipped if interested.

 

Hi Brian
I am defintiely interested in the 'not a lot of expensive tools' version. I am close to deciding if I am doing my belt change or if the car is going in to Rocco's.

Gerrit
http://dino308gt4.com

 

"Ray Charles (RIP) could have tuned a motor to give good peak power"

Brian, few people have the ability to make a point as clearly as you. Here I go laughing out loud again when sitting at the computer. Kris thinks I have cracked
Dave

 

#1 Read what I'll be writing and I'll explain Ferrari's way. It is somewhat streamlined from that. At least on the solid lifter cars.

#2 The is no consistancy there. On some motors when all is correct the marks are spot on. I have also seen them that a cam or 2 is a mark width or 2 off. Even if you want to believe that the marks are in the right place 100% of the time on a 1 inch diameter shaft your eye cannot measure 1 degree of misalignment and 1 cam degree is double the tolerence so even if the marks are correct on the cams you cannot align it with the degree of accuracy required. Also consider this, many of the cars we are talking about use the same cams, same part numbers, but timed different for different markets. If the marks are perfect and are supposed to be used how do we achieve that? And it IS necessary to time them different. As an example the US TR uses exactly the same cams and if I recall correctly the US ex cam is timed different by 4 degrees, not very much. Too little to see. It was done to reduce hydrocarbons at low RPM because the cats of the era could not take that level of HC output. If you use the European timing spec it WILL overheat the cats. I know, I have tried it. Those cams were never intended to be timed by eye and that is exactly why so many people have trouble with overheating cats.

 

I am so happy I am still providing you with entertainment. Too bad the guys in Maranello and NJ didn't always appreciate me.