Pinging

[MRHP]

Reason I ask about jetting is because fuel of today has less btu than the fuel of yesteryear. You may need to richen your fuel curve a bit. As Don said, initial timing, total timing, and where the curve starts and ends are very important. The vacuum advance also needs to be checked when it comes in play, and how much advance it adds to the mix. Lots of things to get right.

 

[Don Jacks]

Those adjustable vac.cannisters ONLY adjust how soon the vac.advance comes in,not how much it advances.There are [Crane Cams] additional parts[or were at one time] that will allow one to limit how much advance that they can provide.A good dial back light,and the willingness to work and put in the time are all that's needed.

 

[rstreet]

Those adjustable vac.cannisters ONLY adjust how soon the vac.advance comes in,not how much it advances.There are [Crane Cams] additional parts[or were at one time] that will allow one to limit how much advance that they can provide.A good dial back light,and the willingness to work and put in the time are all that's needed.

Don correct my problem was the total advance was crazy high due to 70-80’s engine requirements. Unfortunately I no longer recall what that amount of total brought in by vacuum advance was. I am ready for a comment about eliminating vacuum advance but that will definitely help drivability but causes another summertime major issue. I would have liked to have used a 4 gas analyzer during my problems! But now after many hours the car runs so good I haven’t touched a screw in many years. But I did do an oil and filter change.
Robert

 

[427John]

Your distributor can be recurved to give exactly the timing curve your engine needs its just a matter of of determining what it is and building it into the distributor =,as Don said the vacuum advance can also needs to be tailored as well,limiting the amount of vac advance is as important as when it comes in,if not it will be the cause of pinging when you cruise down the road at light load and slowly feather in the the throttle.If part throttle cruise adv is allowed to go too far then its just that much that has to retard when load is increased and vac drops.

 

[Moparboss]

Just set it at 8 and see what it does. Also is your disributor stock with vacuum advance. If so just check advance to make sure it is working and then just drive it and see what it does.

Strange thing. My balancer has a white mark on it. But it’s not on the factory timing mark. I am using the factory mark and I set initial timing at 8 deg. A whole lot better. I still get a tiny bit of pinging at WOT. But Gina run it there much at all anyway.

 

[Moparboss]

Just set it at 8 and see what it does. Also is your disributor stock with vacuum advance. If so just check advance to make sure it is working and then just drive it and see what it does.

It does not have a vac advance.

 

[Moparboss]

Just set it at 8 and see what it does. Also is your disributor stock with vacuum advance. If so just check advance to make sure it is working and then just drive it and see what it does.

Doesn’t have a vac advance. I set timing an 8 deg initial timing. A whole whole lot better.

 

[Moparboss]

Just set it at 8 and see what it does. Also is your disributor stock with vacuum advance. If so just check advance to make sure it is working and then just drive it and see what it does.

Doesn’t have a vac advance. I set timing an 8 deg initial timing. A whole whole lot better

I would first determine what the total timing comes out to before I made any more adjustments.

I ran the motor up pretty good. I don’t have a tach. But I would think it was at 2500-3000. Total timing was 34 with a dial timing light after I set the initial timing at 8 deg. It’s a whole lot better now.

 

[blkblk63ss]

What distributor does it have, interesting???

 

[Moparboss]

What distributor does it have, interesting???

That’s a good question. My 1960 348 with single 4bbl has a vac advance with a protronic conversion. This car has not vac advance but has a stock appearance. I’ll pop the cap off and take a look at what is has inside.

 

[dakota tom]

Small block balancer?

 

[oldskydog]

What year balancer? Before 69 timing mark was in line with keyway, 69 and later long waterpump applications mark was 10 deg off.

 

[Iowa 409 Guy]

Time by ear????

 

[Moparboss]

Small block balancer?

Don’t think so because it looks the same as the balancer of my 1960 348

 

[Moparboss]

Small block balancer?

Don’t think so because it looks the same as the balancer of my 1960

What year balancer? Before 69 timing mark was in line with keyway, 69 and later long waterpump applications mark was 10 deg off.

that’s some real good info. I will have to look into that.

 

[63409impala]

I just use a mechanical advance distributor and curved it so the total timing is all in by 2800 rpm. I dont use a dial back timing light or anything like that. Just a cheap old sears timing light my dad bought back in the 60s. I set my total timing wherever i want it and initial timing ends up wherever it ends up at idle.

 

[427John]

As far as power there is nothing wrong with a mechanical advance only distributor,it just gives up part throttle fuel economy.An example is I have a car with an 11 to 1 compression 427 and 4 speed,I still have the factory mechanical only dual point on it because the engine is all stock and I want to keep it that way but when driving down the road as soon as you let up on the gas a little the engine braking is so noticeable that it feels like you stepped on the brake pedal this wouldn't happen if I had a vacuum advance distributor.I seldom drive the car because the fuel mileage is so bad I joke with my kids about every time I mash the gas pedal an oil well in the middle east caves in.If I had the option of running vacuum advance I would build in a curve with low to mid teens initial and however much mechanical you need to get the total you want by 2800 and still take advantage of the vacuum advance.It will give you a quick starting engine that is very responsive to the throttle and can make the difference between single digit and mid teens fuel mileage depending on gearing and tire size.

 

[Mr Goodwrench]

It would be nice to find reputable shops that still have a working Sun distributor machine taking work. Not easily found these days. None in my area.

I bought one about a year ago, really like it and use it alot.

 

[Don Jacks]

Is that dist.out of your Pontiac OHC 6?

 

[Mr Goodwrench]

Yes, my HEI conversion.