Pinging

[Moparboss]

Hey guys looking for a little help here. I bought a 1959 Impala 348 Tri-Power car. Runs beautiful. However when I get on it it pings. I run 91 octane Chevron in all my cars and motorcycles. I like to think that is excellent gas. Can back the timing off some to take care or this? Do I run octane boost? Any advise would be appreciated. Thanks in advance guys.

 

[La Hot Rods]

What is your timing setting now?
Setting it back would be a good thing for now tell we find out more about what you have.

 

[Moparboss]

It is set initial timing at 12 deg. However I checked it today and it was at 18 deg initial timing. Backed it down to 12 deg it’s allot better but still pings a little at full throttle. Not like I am going to run it there often but from time to pass on freeway may need to get into it a little. Any ideas to eliminate the ping would be greatly appreciated.

 

[blkblk63ss]

Isnt 8 degrees stock for that engine???

 

[MRHP]

May want to check your jetting on the carbs. A lean mixture, along with too much timing, and high engine temps are all suspects.what is your total timing?

 

[Moparboss]

Isnt 8 degrees stock for that engine???

I am not sure. Is it? I was going to set it at 8-10.

 

[Moparboss]

May want to check your jetting on the carbs. A lean mixture, along with too much timing, and high engine temps are all suspects.what is your total timing?

Definitely not running lean. Plenty of fuel. Also this 348 is a nice cool running motor. I am also not sure what my total timing is. How do you check that? Run the motor up to about 2500-3000 RPM and run dial on timing light to check?

 

[blkblk63ss]

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.

 

[62_Conv_2-4s]

Backing down on the timing is one choice but fuel mileage and performance will be impacted. I would try some octain boost with the timing set for best engine performance and see how that goes.

 

[boxerdog]

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

 

[blkblk63ss]

Backing down on the timing is one choice but fuel mileage and performance will be impacted. I would try some octain boost with the timing set for best engine performance and see how that goes.

If factory spec is 8 ,which he can find out for sure on internet or a shop manual, it worked when new and now it don't , really???? Of course he can check total timing to be sure what it is . What i am saying it just looks like a driver not a hot rod and just want to eliminate pinging.

 

[boxerdog]

After 60+ years, there is no telling what might be going on with the distributor, intentional or otherwise. I would want to at least try to figure out what the advance curve looks like.

 

[Don Jacks]

I'm with Dave.I've always felt that a ''Driver'' and a ''Hot Rod'' deserve the same attention to detail for best operation.Get out the dial back and find out how much ''total'' is in there as well as WHERE it comes in at.Then we can determine what kind of curve and initial is needed.As of now we have no idea as to what's in that motor as to compression ,cam, ect.

 

[blkblk63ss]

I'm with Dave.I've always felt that a ''Driver'' and a ''Hot Rod'' deserve the same attention to detail for best operation.Get out the dial back and find out how much ''total'' is in there as well as WHERE it comes in at.Then we can determine what kind of curve and initial is needed.As of now we have no idea as to what's in that motor as to compression ,cam, ect.

Why i asked if it was stock ??? He has not said what he has as distributor.

 

[rstreet]

Time to put that distributor on a working Sun machine! I had massive timing problems with my 348 and the real issue was my vacuum advance dash pot was generic but…. It brought in way too much timing thus pinging at Highway part throttle. Actually mine was falling flat at part throttle highway speeds. The Sun machine will detect that and just make some restrictors out of copper tubing until you get it right! I wound up “dialing” in a 1961 348-280 hp curve when I put the 2 4’s on it. Runs great
Robert

 

[blkblk63ss]

Time to put that distributor on a working Sun machine! I had massive timing problems with my 348 and the real issue was my vacuum advance dash pot was generic but…. It brought in way too much timing thus pinging at Highway part throttle. Actually mine was falling flat at part throttle highway speeds. The Sun machine will detect that and just make some restrictors out of copper tubing until you get it right! I wound up “dialing” in a 1961 348-280 hp curve when I put the 2 4’s on it. Runs great
Robert

Someone did not set and adjust vacuum advance when they installed it.The old unit can be checked with allen wrench on number of turns it is set at to dead stop. The new unit then can be set same number of turns and then can be checked on engine with adjustable timing light.

 

[rstreet]

Someone did not set and adjust vacuum advance when they installed it.The old unit can be checked with allen wrench on number of turns it is set at to dead stop. The new unit then can be set same number of turns and then can be checked on engine with adjustable timing light.

The new ones are generic and not adjustable. Or at least the one I got I think from napa
Robert

 

[IMBVSUR?]

Time to put that distributor on a working Sun machine! I had massive timing problems with my 348 and the real issue was my vacuum advance dash pot was generic but…. It brought in way too much timing thus pinging at Highway part throttle. Actually mine was falling flat at part throttle highway speeds. The Sun machine will detect that and just make some restrictors out of copper tubing until you get it right! I wound up “dialing” in a 1961 348-280 hp curve when I put the 2 4’s on it. Runs great
Robert

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.

 

[blkblk63ss]

The new ones are generic and not adjustable. Or at least the one I got I think from napa
Robert

See them all over the place .If it wasnt adjustable then it should have not been used.

Accel 31034 - ACCEL Points Style Adjustable Vacuum Advance Canisters​

( 18 )

Part Number: ACC-31034

 

[blkblk63ss]

New HEI Adjustable Vacuum Advance Fits all 6 & 8 Cylinder HEI Distributor​