Can't get my engine to quit "pinging".

[Bentworker]

What octane fuel are you all running?

 

[csgt428]

I set my timing to around 8*. Total advance looked to be in the 34*- 36* range. It has an old mech adv dual point dizzy in it. I think it's a Mallory. I have an 850 cfm double pumper Holley on it. Still haven't changed oil. Need to drive and check for pinging now....

 

[csgt428]

What octane fuel are you all running?

91oct non ethanol premium now. I think I had Old gas in it, year old if not older. But I just filled the tank so most of it is fairly fresh now. Taking it for a test drive....

 

[basstrix]

@csgt428 That's one hell of a collection you got there!

 

[boilermaster]

cstg428,
hope those specks didn't ping, but I am guessing that you are going to want those 8 degrees of initial back at some point.
problem is you have too much mechanical advance in that distributor to do that safely.
Most here that run 408 engines like 32-34 degrees all in and 14-16 degrees initial.
Me thinks that Mallory distributor may have some tiny little set screws under the breaker plate
that will limit your mechanical advance.
Boilermaster

 

[boilermaster]

csgt428,
I see that your camshaft 32-431-8 is a hydraulic roller,did your mallory distributor come with a STEEL gear or has it been converted to one ? you absolutely have to have the correct distributor gear in there or damage WILL result.
Boilermaster

 

[Hemikiller]

I set my timing to around 8*. Total advance looked to be in the 34*- 36* range.

If you were running 16° initial before and have ~28° mechanical in the distributor, that's the cause of your pinging. Closed chamber heads typically want 32°~36° total. If I'm reading it right, you were up around 44° total.

 

[csgt428]

csgt428,
I see that your camshaft 32-431-8 is a hydraulic roller,did your mallory distributor come with a STEEL gear or has it been converted to one ? you absolutely have to have the correct distributor gear in there or damage WILL result.
Boilermaster

Uh oh. How do I tell if it's steel? Took it for a drive, still pinging under a load. I'll pull the dizzy out and check the gear..... I think I have one I could put on if it's wearing/galling.

 

[csgt428]

If you were running 16° initial before and have ~28° mechanical in the distributor, that's the cause of your pinging. Closed chamber heads typically want 32°~36° total. If I'm reading it right, you were up around 44° total.

I set it to 8* initial yesterday and it went to about 34* all in. took for a drive. It is still pinging. That 16* was for the HO engine anyway, which this engine is Not.

 

[csgt428]

cstg428,
hope those specks didn't ping, but I am guessing that you are going to want those 8 degrees of initial back at some point.
problem is you have too much mechanical advance in that distributor to do that safely.
Most here that run 408 engines like 32-34 degrees all in and 14-16 degrees initial.
Me thinks that Mallory distributor may have some tiny little set screws under the breaker plate
that will limit your mechanical advance.
Boilermaster

I may try a different dizzy. I don't like points and dual points even less. I wonder if that dual point dizzy is the reason my factory Tach quit working?

 

[csgt428]

@csgt428 That's one hell of a collection you got there!

Thanks, want one or two? I need to sell a couple just to have inside storage for the rest!

 

[basstrix]

I'd love to have the 70 Q code Mach I or the 71 C code Ranchero.....but honestly, they are all desirable.

 

[csgt428]

Those are two I've thought of selling. Some I wouldn't even consider selling like my 66 and 68 fastbacks. If I sold the 70 Q code I'd keep the 69 Mach and vice versa...

 

[csgt428]

If anyone has an original 72 351c HO engine for sale I'd be interested!

 

[boilermaster]

csgt428 take a pic of your current distributor that includes the model and serial number so we know what you have.
either way you are going to need a working tach and most aftermarket electronic distributors are not compatible with a factory tach (i went rocketman conversion and MSD # 85771 distributor (steel gear and ignition box required)
You will want a distributor that can provide 10 degrees mechanical advance (dist.) or less to run 16 btdc
initial timing.
pretty sure you already know that your engine does not appreciate your current 8 degrees btdc initial.
Our engines are nearly identical internally and I know what mine likes and dislikes.
Boilermaster

 

[csgt428]

csgt428 take a pic of your current distributor that includes the model and serial number so we know what you have.
either way you are going to need a working tach and most aftermarket electronic distributors are not compatible with a factory tach (i went rocketman conversion and MSD # 85771 distributor (steel gear and ignition box required)
You will want a distributor that can provide 10 degrees mechanical advance (dist.) or less to run 16 btdc
initial timing.
pretty sure you already know that your engine does not appreciate your current 8 degrees btdc initial.
Our engines are nearly identical internally and I know what mine likes and dislikes.
Boilermaster

OK. I need to decide what dizzy to use first. I'm still hoping it just needs broken in. I might do that first, then concentrate on the tuning.

 

[boilermaster]

csgt428,
if you changed out an advance spring by simply removing your cap and rotor, check out MSD 8464 advance spring kit on summit racing (yes they fit Mallory distributors.
look at the instructions, you will want the largest (black) bushing to get to 10 degrees distributor.
also pretty sure your distributor has a steel gear.
Boilermaster

 

[csgt428]

csgt428,
if you changed out an advance spring by simply removing your cap and rotor, check out MSD 8464 advance spring kit on summit racing (yes they fit Mallory distributors.
look at the instructions, you will want the largest (black) bushing to get to 10 degrees distributor.
also pretty sure your distributor has a steel gear.
Boilermaster

My engine paperwork calls for 32* total. If I limited mech adv to 10* and went to 16* initial that's only 26*, so I'd need 16* mech adv in dizzy, right? It seems to have 24*-26* mech adv in it now. I wonder if the Mallory dual point is even worth keeping in there... If it will spin the engine to 7k rpm I suppose so..... to bad my tach quit!

I have a Dura spark dizzy I could put a chevy style (but Accell or Holley) module on w the old style four spade connectors and a small homemade harness and be rid of the ford box and harnesses. But then I'd have vacuum adv again....

I also have some old Ford point dizzys I could use with a pertronix system.... vacuum adv again.... but stock looking

OR... just bite the bullet and get a good aftermarket Dizzy for it. Hmmmmm.....

 

[boilermaster]

csgt428,
sorry your math is wrong if you want 32 total and 16 initial you would want 8 distributor.
distributor degrees = X2c at the crankshaft.
I f you verify you have a replaceable type bushing, I think I can find my secret bushing paperwork
that C9ZX told me about.
Boilermaster

 

[CandyRcode]

Put a few gallons of 110 race gas in it. Then see.