I'm expecting my dist. with the new pertronix units back any day now. Can someone give me a quick run down on timing the engine? I've got the basics (where to hook the light, I found TDC and it's marked, etc.) but I have some questions. First, a buddy helped me time it last time I had the dist off and his timing light had a digital read out on the back that he could adjust that setting and the engine note would change. Don King is doing the work. He told me I'd only need to set the timing on the front bank since everything will now be fed out of that one dist (no more points, 2-pertronix in one dist. - still have two coils). This assumes my 5-8 bank is good. Should I check that as well (I would guess a quick check would be in order). Once I set it at idle, do I need to double check the advance? I know he just rebuilt the unit and checked it on his machine, but if I wanted to check it how would I? Run up the engine to the advance RPM and watch the settings (is that what the digital read out was for on the light???). Thanks
My experience with with a 2V carb car. I was advised to set timing at 5000 rpm. Then, check again at idle. If it doesn't line up at idle then there is a problem with the advance mechanism. So, to go through the whole process, I started by adding paint to the flywheel at the AF7 and AF34 marks for both the front and rear banks. Check your WSM as the exact marks differ model to model. You need to know you are at PM1-4 on the rear bank. If it wasn't set there when the distributors came off I would be tempted to pull the rear cam cover and make certain the #1 valves are closed so you know you are at TDC on #1. Position the flywheel to the idle mark. Install the rear distributor with the rotor pointing at the notch in the distributor case (ie at #1). Now rotate the crank 90 degrees clockwise. Line up the flywheel on the idle mark for the front bank. Install the front distributor pointing at #1 (ie post for #5 cylinder). The above should get the car started. Then set the timing at 5000 rpm using the mark for 5000 rpm (was AF34 on my car). Let the car go to idle and check timing there. Repeat for the other bank. Seamus
Don did my dizzy back in 2000. Just put back the dist with # 1 at TDC (PM1-4). Start it up and set the timing at 7*BTDC and lock it down. You don't have to touch it again . It is quite simple. Don does a super job.
Most important is to make sure you are getting full advance at higher rpm. Tough to get an exact 7 at idle and 34 right at 5k. Many I have looked at sit above 7 at idle in order to get full advance, and although there are not any more timing numbers on the flywheel, I would guess they were at 11 or 12 at idle. They ran fine at that, and mine runs fine like that. 34-36 total advance is safe, but I have heard of others who go even higher than that.
When Don sets up the dizzy it will run the correct advance when installed in the car. My 77 is dead on 7* at 1000rpm and all of the timing marks are on the flywheel. It will run to spec. at 5000 rpm so you won't need to check it but if you want go ahead. As I mentioned before I have not touched my dizzy since I installed it back in 2000. Enjoy the ride
the engine was a TDC when I removed it. I took off the oil cap and also verified that the cam tick marks were lined up (all this also lined up with I did the 30k 3-years ago). Don rebuilt the dist. and made sure it advanced correctly when he installed the units. It arrived yesterday. I'll pick up a timing light on the way home and install it tonight and see how it goes. I'm hoping I'll have better spark than before.
When I swapped my distributor I checked advance at 1000 RPM increments up to 5000 RPMs (my redline is 6500) to be sure the springs were okay. A friend had a timing light that varied the strobe to tell you what the advance was; way cool and easier than color coding the flywheel! You should be able to find an advance curve for your engine somewhere if you want to do the same. Ken
I created a set of leads for these purposes. I got the idea from someone in my office. I got about sixteen feet of 12 or 14-gauge double wire from someplace like Radio Shack. I put something like a 10 or 20 amp fuse in place on the positive end. I created it in order to get power to test components away from the battery. Turns out it really became useful when I needed to power the tachometer and timing light at the opposite end of the 308. So I just hook it up to the 308 battery and let it power the test equipment at the other end. Seamus
I usually clip on to the +12v feed line into the coil. You can also unplug the connector that feeds the licience plate lights and clip on to that . Only need to turn on the parking lights for a feed.
Is there a 7°BTDC mark on the flywheel ?? My timing light does not have the feature to set advance internal on the light while checking the mark at TDC.
It's best to mark it yourself White-Out or enamal paint. I have white at 0, red at 12 degrees, white dot at 20 deg., two dots at 35. Much easier to see than reading those scratches! My light also isn't the variable kind. You should mark 0 and 7, and your max advance point at least. Ken
I guess what I meant was, are their tick marks on the flywheel so that I can put a white/red dot on the flywheel. I don't recall seeing anything but maybe I did.
Can't say for a Ferrari. I'm sure 0 degress is marked but there's no guarantee that the mark is actually 0. Most flywheels have a double line at 0. Mine is marked at 10, 20 and 30 degrees as well and I'd be surprised if yours wasn't. My advance is nowhere near the reccommended 6* because that's for emissions. As mentioned, I have my advance at the max the engine can take which is about 11. Again, your car may indeed be happiest at 7; my compression ratio is higher than yours and that makes a difference. Ken
There is indeed a 7°BTDC mark on the flywheel. I marked it with white paint (TDC was red) and timed it at 1000 RPM. Thanks all.
