Technical 40 degrees of initial timing?? WTF?! (347 stroker)

What timing set are you running? Is it adjustable? If it has more than 1 set of marks on it, are you absolutely sure you're on the correct set of timing marks?

If you used the wrong set of timing marks on the sprockets, your crank could be TDC, but your cam far off.

 

I'm 99% sure that I put it in correctly, it came with the cam from Lunati; double roller timing set with 3 different spots on the sprocket (straight up, -4deg and +4deg if I remember correctly). In the event that I didn't set it up right, wouldn't the engine run like absolute garbage? And would it read 40+ degrees on the balancer?
Edit: I installed it dot to dot btw

 

You have your pointer at the wrong ZERO on your balancer. Try moving it to the other ZERO and see what you got. I'll bet your timing will be right. That balancer is for multiple TDC locations so you have to use the one that is right for your application. It will not start at +40.

 

Not necessarily. My father in law built a SBF and used the wrong set of marks, the engine started easy and would idle smooth, but had trouble pulling through the power band.

 

You are saying all the timing marks line up, cam/crank, pointer/TDC on 1 and No1 on distributor! BUT is No1 on distributor , where the rotor is pointing when all the other marks line up? Did you check this as you stab the distributor into mesh with the cam gear? If not the rotor will be pointing to another terminal, which will effectively become No1 even if it is not numbered "1" on the cap

 

I would forget about your marks on the balancer. Wrap the balancer with some yellow tape, get top dead center on number one. Measure the diameter of the balancer, multiply it by 3.14, divide it by 360. Mark your balnacer with 0,5,10,15 etc. Then start the car and check it with your timing light.

 

Sounds like he knows where TDC is and has his light connected to the #1 plug wire. An adjacent firing wire would be close to 90º off when the engine is idling decent.

@Jimbo Nettles are you using a dial back timing light? If so, is it set up correctly?

 

Curios with all these responses on how it wouldn’t even crank.. I run 2 different sbf motors with locked out timing, one at 36 degrees and one at 38 degrees. Both crank just fine. Some sbf combustion chambers love tons of timing. I have a friend with an iron headed 331 that runs 43 degrees total.


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I am, all the readings I took were with the dial at 0, I even checked with 2 other lights, same readings

 

Holy s**t, this is entirely possible... What do I do if my timing pointer doesn't reach the other 0?

 

That is the complete opposite of my experience but all my sbf have been 10 to 11 cr..

 

Take the car for a drive and see how it runs.
I haven't used a timing light in 30 years, and when I did, I only used it to set the total timing at 3,000 rpm.

Connect the vacuum advance, start the motor, bring the rpm up to 3,000, turn the dist for the best rpm, back it down just a bit, lock down the dist, and test drive. Listen for pings or misfire, adjust as needed. When its good, turn off the motor and then restart it. If it kicks back against the starter, reduce the timing a bit until it doesn't kick back against the starter, then do another test drive. The happy medium is between the ping and starter kick back. I guess you could hang a timing light on it to see what its running at, so in the future you know where to start.

Every motor, in every vehicle, on any given day, has its sweet spot for that combination. A timing light is to get you close so it takes less time to dial into the sweet spot. If your running your motor off a timing light at set degrees, you may be leaving performance on the table. Gene

 

I think your timing readings are not fouled up like you think. With that big cam in that little motor, it is supposed to idle like crap at stock timing, if it will run at all. You can't just crank up the initial timing to smooth it out without knowing what your total timing will be. Total is the initial timing at idle, before the mechanical advance moves, that you set by twisting the distributor, plus the mechanical advance that comes in as the motor speeds up. When you increase the initial, you have to make a corresponding cut in the mechanical, so the total is at 34-40, whatever you motor likes. All of this is with no vacuum advance hooked up yet. We need to run a lot of initial timing in our big cam motors, and then cut back on the mechanical advance to limit the total timing. Try this: Use a timing light to set your initial timing to 20 degrees with the engine idling as slow as possible even if the idle is ruff. Then rev the motor while watching the timing marks to see how far it advances. Lets say it goes to 50 degrees. That tells you that you have 30 degrees of mechanical advance built into the distributor. I would start out with 15 mechanical, plus 20 initial, so you have 35 total. Different distributors have different methods of how to limit the mechanical advance. Once you've done that, it should run at 20 initial. Verify the 35 total, then plug in the vacuum advance to full manifold vacuum. That will pull in another 10 to 15 degrees, and help get you a lopey. but controllable idle at about 900 -1100 rpm.

 

my motors are 10.5:1 and 11:1. Sbf combustion chambers are very efficient quench chambers. Very common to run low to mid 40’s on a well tuned engine.


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You said yes so that is out which leaves us to.

Get one that does or make one and see if your timing light agrees with it. Worst case is make your own timing tape, put it on the damper as Anglrdrive says above and then check it

 

In his very first post he said he did the piston stop method to find TDC, and it coincided with the mark on the balancer.

 

If he infact did this and his marks on the damper are correct he should have laid a mark on zero on a scale. His pointer should be on that mark with the roter pointing at #1. It's that simple but with the crap coming from China who knows how accurate the damper is. I bought one of those ajustable pointers for my 289 and pitched it in favor of one I made, it was junk.

 

Lining up the rotor with the cap gives you no indication whatsoever of your initial timing. You could have had it set way advanced that way. To rough in the static timing, rotate the engine to 10 or 20 degrees BTDC, or whatever you are trying to set your initial timing at, using the marks on the damper. Get the rotor pointed in the right general direction, but then for accuracy turn the distributor body to line up the tip of the reluctor wheel with the reluctor sensor. That will get you way closer than pointing the rotor.
When you ran it at idle with 40 degrees initial, then added RPM which adds perhaps 25 degrees more timing thru the mechanical advance, the spark could be jumping to the next terminal on the distributor cap. There is 90 degrees of crankshaft rotation between each spark. When you get your total timing up in that 55+ range, spark jumping terminal to the next plug can happen unless the distributor is carefully phased to prevent it.

 

So when you get a good idle and vacuum, does it buck against the starter when you try to start it? If it doesn't, that makes me think there is something wrong with the way you are using the timing light. If it does buck against the starter then I'm at a loss unless you actually have a starter problem.

I had a similar problem with my Y block. I could never get the timing light to read properly, timing was way advanced. I finally timed it with a vacuum gauge and drove it that way for 4 or 5 years. When I pulled the engine to overhaul it I found I had been using the wrong cylinder to time it. On a Y block the farthest forward cylinder is not number 1.

 

Gene nailed it in his post above. Do it this way and you'll be well on your way to being able to actually tune your engine. Setting things up with a timing light is ideal, but being able to troubleshoot and/or delineate the difference between too much and not enough timing, etc. is priceless.

If you had 40 degrees advance at idle plus whatever the distributor has in it for total, chances are the engine will tell you something's wrong, which doesn't require a timing light. Detonation, pinging, no power, etc.

More times than I can count, I've set an engine up with a timing light only to manually set the timing after the fact to adjust for detonation, hard starting, etc.

 

I understand the need for timing for a big cam, but I was under the impression that my cam was mild? When doing my research I wanted to avoid any racy type cam as it lives in a fairly heavy truck that I use as a truck. Maybe I'm completely wrong, I just assumed that cam was on the mild side.

I somewhat confirmed the mechanical advance in the dist, 23 degrees by 5000 rpm, honestly I was scared to rev it more than 3000 rpm, but the readings I got matched what the chart that came with the dist said (19 deg at 3000).

I have stiffer springs that came for it, 20 degrees by 5000 rpm (which honestly I probably will never see in that truck). You recommend I install those?

 

No, when I time it "by ear" everything works fine, starts right up, idles fairly around 800rpm. It's only when I put it to say 8deg advanced by looking at the balancer that it bucks and won't start. The balancer is definitely "lying" because if it was really 8deg before tdc on the compression stroke of #1, it'd start right up. Which makes me think that Warhorseracing is onto something with my timing tab being in the wrong location for my balancer with multiple TDC marks

 

Fully agree with you, if I take the timing light/balancer out of the equation the engine runs pretty good all things considered. This seems to be backed by the sensors on the sniper, and various other things (like no weird color smoke out of the tailpipe, no obvious miss etc)

 

Disconnect that vacuum advance and remove it all together. If you know how to tune you don't need that..

I would look at the ignition and if you cant find anything remove all that and put the single points distributor ,Delco coil with resister all back in.. Remove the vaccum advance and screw the points plate to the base of the distributor..
There is so much weird shit that goes on with that ignition.. If you want more power, connect a MSD6AL or the Vertex Z-6 CD box and use the distributor to trigger the box.. That is hands down one of the best street ignitions going..

 

Try using a different distributer. What it sound to me like is that your control mod is wonky. I have had to deal with that problem with aftermarket HEI type of distributers before. I even had one that tested good, and after a few days out of desperation I pulled the distributer from my truck and tried it. Cured the problem.

 

Totally stock 302 likes 12-14 Degrees initial advance and every engine is different but no more than 32 Degrees all in by 3200 RPM. If you are at 40 it will not start. Make a new pointer and time it to that. Drive it conservatively and monitor for detonation. If it likes it. problem solved.

 

Another thing I thought about, my current Mac timing light adds 10 degrees of advance up front. If you set the timing to TDC, it is actually 10 degrees advanced. You have to use the buttons to back out the 10 degrees if you want to see actual timing. It has confused me more than once.

 

Try a timing light that isn't dial back. Not sure about Pertronix, but some MSD units and dial backs don't play well and your timing can show to be off by 10-15 degrees. I know an MSD6 doesn't like them, but I never had a problem with my MSD7AL box.

Timing all in at 5000 ? It should be all in around 3000 on a street motor.

What is your idle RPM when all of this is taking place?

 

Stupid question time: what does detonation sounds like?

 

Valves pinging. Caused when the spark is too far advanced and the compression actually slams them shut causing a metallic sounding ping.