Eliminate Pinging

Looking for the best way to eliminate or reduce the pining I get under load for my 69 429 2bbl Mercury Marquis. I know the engine is supposed to get a higher octane gas then is now available in most gas stations here in Ontario. Are there any timing tips or fuel enchantments. octane boosters etc. that would help with this issue?

Recurving your ignition timing advance and/or changing your initial timing will usually help. A lower temp T-stat, a bit richer carb tune, different vacuum advance canister(if vacuum advance is used) are other things that can help with a pinging issue.

aquartlow wrote:Recurving your ignition timing advance and/or changing your initial timing will usually help. A lower temp T-stat, a bit richer carb tune, different vacuum advance canister(if vacuum advance is used) are other things that can help with a pinging issue.

All This^^^^^^. If you are going to use vacuum advance They make different length arms on the vacuum pod shaft that used to be numbered in amount of degree's it will pull. You can also get vacuum pods with an adjustable spring tension through a screw under the vacuum line nipple. The other trick is to drill the arm and put a small roll pin through it to limit the amount of travel were you desire the amount of advance to stop.

The slots can also be welded smaller for the mechanical advance if need be.

http://www.reincarnation-automotive.com/Duraspark_distributor_recurve_instructions_page-2.html

Nice chart in this link for the width of the slot and the amount of degrees it will advance. It's for DuraSpark but, should work for points type distributors also.

A slightly colder spark plug may help also.

All oem BBF distributors had adjustable vacuum advance dashpots.

Is your ping at part throttle or heavy to WOT?

Thermostat temp?

I assume that the engine is unopened and has the original high compression pistons???




S

The Mad Porter wrote:All oem BBF distributors had adjustable vacuum advance dashpots.

Is your ping at part throttle or heavy to WOT?

Thermostat temp?

I assume that the engine is unopened and has the original high compression pistons???




S

She is bone stock and the pinging occurs under heavy load at about 3/4 throttle. It has improved somewhat after I installed a Ignitor ignition module in the distributor. She normally runs around 190 F.

Buscop wrote:

The Mad Porter wrote:All oem BBF distributors had adjustable vacuum advance dashpots.

Is your ping at part throttle or heavy to WOT?

Thermostat temp?

I assume that the engine is unopened and has the original high compression pistons???




S

She is bone stock and the pinging occurs under heavy load at about 3/4 throttle. It has improved somewhat after I installed a Ignitor ignition module in the distributor. She normally runs around 190 F.

This is not surprising nor unusual.

Some ways to mitigate this:

160 thermostat with cooling system adequate to maintain.
Duct cool air to a single or dual snorkel air cleaner.
Jet carb on the rich side.
Limit total timing to 32 or down to 30 degrees if the above fails.

There is a Race Gas additive that Carl and others are having good results with. Check out the following thread.

http://www.460ford.com/forum/69-vendor-sale/228793-race-gas-concentrate.html

The reality here is that the high compression and short cam timing like 96+ octane R+M/2 fuel especially at 190 F running temps.


S

The Mad Porter wrote:All oem BBF distributors had adjustable vacuum advance dashpots.

Do you turn the Vacuum advance in or out to reduce pinging?

pkerot wrote:

The Mad Porter wrote:All oem BBF distributors had adjustable vacuum advance dashpots.

Do you turn the Vacuum advance  in or out to reduce pinging?

CCW limits travel and stiffens the spring. CW allows more advance with less vacuum.

All D/S distributors have too much vacuum advance for a non EGR application. Modern fast burn chambers like the SCJ, P-51 and AFR need less as well.



S

The best way I know other than lowering the compression ratio is to run it cold or simply buy good enough gasoline.

The Mad Porter wrote:

pkerot wrote:

The Mad Porter wrote:All oem BBF distributors had adjustable vacuum advance dashpots.

Do you turn the Vacuum advance  in or out to reduce pinging?

CCW limits travel and stiffens the spring. CW allows more advance with less vacuum.

All D/S distributors have too much vacuum advance for a non EGR application. Modern fast burn chambers like the SCJ, P-51 and AFR need less as well.



S

I turned my vacuum canister's adjustment screw all the way CCW(actually ran out of threads) but still had a bit to much advance. For my application, I had to drill a hole in the vacuum canister mounting tab, between the mounting screws and insert a #6 screw to limit the vacuum advance to 11-12 degrees(originally 24 degrees). Doing this eliminated the surging issue I was experiencing at part throttle/low cruise rpm. Hope this helps in any way.

Edit: I have found that a vacuum advance canister for a '74 F100 w/ 390 has one of the lowest total degrees of advance, something like 12 degrees. If you look at the advance arm on these canisters, they have a # stamped into them, this # is "supposedly" half of the total advance.

aquartlow wrote:

The Mad Porter wrote:

pkerot wrote:

The Mad Porter wrote:All oem BBF distributors had adjustable vacuum advance dashpots.

Do you turn the Vacuum advance  in or out to reduce pinging?

CCW limits travel and stiffens the spring. CW allows more advance with less vacuum.

All D/S distributors have too much vacuum advance for a non EGR application. Modern fast burn chambers like the SCJ, P-51 and AFR need less as well.



S

I turned my vacuum canister's adjustment screw all the way CCW(actually ran out of threads) but still had a bit to much advance. For my application, I had to drill a hole in the vacuum canister mounting tab, between the mounting screws and insert a #6 screw to limit the vacuum advance to 11-12 degrees(originally 24 degrees). Doing this eliminated the surging issue I was experiencing at part throttle/low cruise rpm. Hope this helps in any way.

Edit: I have found that a vacuum advance canister for a '74 F100 w/ 390 has one of the lowest total degrees of advance, something like 12 degrees. If you look at the advance arm on these canisters, they have a # stamped into them, this # is "supposedly" half of the total advance.

I've noted that some canisters have a numbered arm but most do not.
Also of note is that some of the remanned canisters do not adjust well and I am forced to drill and mechanically limit advance to 10 to 12 crank degrees. No rhyme or reason it seems. The new canisters usually adjust well and cam be pulled back to less than 10 crank degrees.

Cardone has a line of new distributors with cap included that are pretty nice for the price. Double check the gear depth though...


S

aquartlow wrote:



Edit: I have found that a vacuum advance canister for a '74 F100 w/ 390 has one of the lowest total degrees of advance, something like 12 degrees. If you look at the advance arm on these canisters, they have a # stamped into them, this # is "supposedly" half of the total advance.

Ebay says, "Need more info" What is the part number?

Try Standard Motor Products #VC 230, can also be found on Rockauto.com. Hope this helps.

^^^ Ordered one. Thanks!

Post details after installation, these are "supposed" to be adjustable with an allen key as well, just like Scotty-The Mad Porter mentioned the vacuum advance canister tuning procedure in a previous reply. Hopefully this one will "fit the bill" and help with solving the pinging issues.

I ran into this, I actually found that the motocraft 2 barrel was slightly rich on the main circuit high vacuum setting, then lean on the low vacuum "enriched" or powervalve open vs. closed. I found that bigger jets helped, however then the high vacuum was pig rich, so I went down in jet size and drilled out the power enrichment circuit, problem solved and better performance while low power cruising as well. are you running a motocraft 2100 or something similar?