Pinging

-
highflyer

highflyer

Well-Known Member
Joined
May 10, 2010
Messages
1,499
Reaction score
39
Location
oakley ,cal
I stated the car is pinging on light throttle...I had a vry light spring in the dist and the lightest stocker with it..was terrible...kkkkkkkked all the time under light load.very light...i checked the timing ..8 degrees and iv changed the top hat adv plate and put one in that limited my adv to 30 degrees[ slot length is .430] at a light 1650 rpm all in.[discconnected adv module]..for a total of 36 to 38 degrees..decided too light of a spring .took it apart put in two of mopars stock light springs and the adv is all in at about 28 29 hundred rpm...went back out and it still pings but not like before..step on it and it still pings but not like it was...pings on throttle then seems to stop while its coming on....any ideas...pls...j[360 reworked mopar 1973 dist..and sh3t for gas.
 
Probably needs to be limited to like 34 and all in by 3K. Must have some compression.
 
38 is a bit high. if you are running premium fuel should work but you will have to make sure it is not running lean. start around 32 and go up till it pings then back off 2 degrees. would be nice to know A/F ratios though. if you are running vacuum advance that may be pulling into much timing under light loads also. try unhooking vacuum advance and see if it goes away.
 
Hi there.
Be sure its not a pump shot issue, sometimes a lean shot makes it stumble upone cruise acceleration.
Imo you can run the total timing as high as it wants without pinging, but keep the intial timing low enough for it to avoid kick back from the starter when hot starting the car.

So how much compression does this mill have?
 
Pump shot is good piece of advice. I went from the stock #31 shooter to #35 on my 600 after the cam swap in the 318 but more of a remedy for a stumble than a ping. I'm concerned about the detonation with such a low initial timing. Even a stock 360 I would imagine would like 12* or more. I run 16* initial & 34* total, all in by 2500 and the mill loves it. Any ping with vacuum adv disabled?
 
He did say he has 30 degrees mechanical with light springs didn't he? I personally would limit mechanical advance to 20 and set initial to 14. you can go up some and see what happens but alway go down 2 degrees from ping to comp for extreme temps. If you are running vacuum that is most likely your source of detonation. Mine actually started to buck and loose speed when the throttle was returned to near closed from a moderate to aggressive acceleration. (unhooked vacuum hose, plugged it an drove home). Most cans will have at least 16 degrees under light throttle and some as high as 30!
 
I cut the slots at .430 which is 30 degrees [checked]and my can is 11 so ill have to weld em up again and recut to get about 20.. ill run it and get the garbage gas out of there and put good gas back in and reset and retest...ill be back when that's all done..thanks all..j
 
highflyer said:
I cut the slots at .430 which is 30 degrees [checked]and my can is 11 so ill have to weld em up again and recut to get about 20.. ill run it and get the garbage gas out of there and put good gas back in and reset and retest...ill be back when that's all done..thanks all..j
Click to expand...

18---20 is a pretty good starting point for even a mild engine

Here's a chart I found on the www. Slot lengths are distributor degrees................

Dimensions for Mopar distributor slots, in DISTRIBUTOR degrees

Modifying advance slots
degrees / slot size
6.............. .340
7................355
8................375
9................390
10...............405
11.5 ...........420
12...............435
13...............445
14...............460
15...............475
16...............490
17...............505
18...............520
 
carb 1405 with 1406 jetting and springs...rpm manifold erson tq20h cam 4 speed overdrive trans I think its 3.09 first gear but not sure..355 in the rear....pulled hose off dist and still kkkkkkkk......pinging..j
 
I would think the stock 1405 jetting would he closer than the 1406 jetting.
The 1406 is jetted leaner than the 1405.
 
When i was in high school i had a 1970 Chrysler with a tnt hp 440. Cheap gas would make it ping regardless of how the timing was set. My dad zero decked a 318 and it was the same way. 93 octane or ping lol.
 
it sure kinda sorta sounds like that 360 has 11:1 or higher pistons. all the timing changes in the world wont help.

can you find out the history of the rebuild? do you know someone that can do a compression test?

if they are high compression domed pistons, you have 2 choices.
1. run race gas
2. get a carb for E85 (quickfuel sells them) and run E85. if it's available in your area.

if it's not high compression, it's something else. probably not pinging, but some other noise. maybe you have a solid lifter setup and needs adjusting. they make some noise. if it's a hydraulic lifter cam, maybe you have a bad lifter or two. it could be a lot of things.

did the person you got the engine from tell you anything at all about what was inside?
 
you could bring it to my house and i will get it dialed in.....
 
ohhhh now l like that idea...now im chasing more gremlins...yes one prob is nasty gas,,,it has a additive in it and im not going to do anymore with it until I get a new adv plate welded and recut and burn that crap out of it..pistons are stock compression and hyd cam..165 across the board on compression ..no carbon buildup new motor..less than 500 miles..no lifter noise..also chasing an electrical prob...j
 
Highflyer,I would seriously consider Bad440's proposal. Will save mucho time,and frustration. Man,got skills.
 
Yes I am definately...I got rid of the bad gas..stuff wont even evaporate..lol....put in some chev super and stuck the old dist back in...pinging gone....now when I have a few minutes ill get another adv plate welded up and cut with shorter slots and try again...till then thanks all....j
 
hello all
Glad to have come across this posting, I've asked similar question about my 74 Dart
stock....
Timing is factory, 750rpm tdc....
these are Cardone (ok, ****) I've gone through 3 of them, my originals
vacuum pot went bad, traded it in, next one gave that same simptems
of not being able to acceslorate fast, engine hesitates, backfires.
traded again, then she pinged with hardly any pressure on the pedal...
traded again, then had no the backfire and hesitation again.
traded back again, now after the engine warms up, she pings at 25mph,
and she hesitates and backfires, at hard acceloration...
I know its a Dist problem, just would like conformation as to why,
is it bad Dist bearing, heating up making the Dist wobble or ?
Best
PS I'm going to a new Dist when I get from a trip I'm taking, any suggestion
this is just a daily driver,,,stock 2bbl carb 904 trans..
gets about 12 mpg in city driving...
 
You must log in or register to reply here.
-

Back
Top