Quick timing question 1978 GTS

From the distributor side of the engine, there is a plate in front of the oil filter. Remove the bolts and remove the plate. That will expose the timing marks.

 

I don't know if this was designed in, or just worked out that way, but a great heads up to be at TDC #1 on the power stroke (as opposed to TDC on the exhaust stroke) is to look thru the oil fill cap, and you can see the 1-4 intake cam alignment mark. Comes in very handy if you remove a distributor.

There are two groups of markings for the 2 distribs. they get set to their corresponding mark.

 

Yes, that's correct.

The 3 deg ATDC spec only applies if your R2 points are still present and working. If you only have the R1 points, you'd set both banks to 7 deg BTDC. There are two sets of marks on the flywheel -- one set will be labeled PM1-4 (for the 1-4 bank) and the other PM5-8 (for the 5-8 bank).

Yes -- you'll wish your marks were as clear as these:
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but they typically look more like this (so Mechanics often add some corresponding paint, or nail polish, dabs to the pressure plate housing to be able to see them when running -- and maybe use different paint colors for 1-4 vs 5-8):
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Thanks for those pics Steve. I've been having issues with setting timing on my '78 also and this helps a lot!!

John

 

But also remember, there are four diff. timing on the 308:
1: front bank valve timing
2: front bank ignition timing
3: rear bank valve timing
4: rear bank ignition timing

 

Here you go.....
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Well, yea, but the flywheel is for ignition!!

 

Well, yea, but you do need the flywheel for valve timing too, since you have to be sure you are at TDC when you are playing around with the cam gears, belts, etc.

 

+1, You can't get an accurate/true ignition timing even if your valve timing is off by a tooth,
which I think is about 4deg.

 

Adding a little something to this regarding tdc. On my own engine I found that true tdc is about 1 degree to the right of what Ferrari has marked as tdc. I was running initial timing at about 12, when it was actually 11. Total timing wad at 38 when actual was 38. Food for thought.

 

Right but in my case if the car was running, I pulled the distributors and am putting them back in.... the cam timing should not have changed. All I needed was a better picture of what it is I'm trying to decipher down in that little hole!

 

Total is certainly more important than idle, unless you drive around REAL slow.....LOL!

 

I will add that what helps me are not marks on the housing, which are helpful for seeing what's what while rotating the crank, but putting the paint or nail polish on the mark itself such as the AF7 mark really helps when using the timing light.

And, yes, in a real (driven) car it's hard to make out that stuff.