Pinging

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69signetv8

69signetv8

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In the past I have always had trouble timing the engine with a light and end up doing it by a vacume gauge and ear! If I use a light and try for a factory setting about 8/10* before the engine will die. I have a true TDC. When I use a vacume gauge and adjust the dist to get max vac she idles well and the performace seems good but pings bad. I've tried a few things as advancing or retarding the timing but she still pings. I use + gas 89 octine.

Although I've read other posts I'm not up on the "total" timing thing and not sure how to tweak outside from moving the dist back and forth!

Sould I start playing with the screw in the vacume can?? If so which way do I turn it and how much??

This is the stuff I hate:shaking:..Wish you were here!
Thanks
 
:sign3: Is this a hard question? or just so simple "I" should be able to figure it out myself??
If anything...can someone at least tell me about the allen key in the vacume can. I think I've tried everything else advancing and retarding the dist...
BTW, it's on the right port!:notworth:
 
this kinda covers the vac pot

http://www.sweptline.com/tech/engine2.html

What seems to be the problem using the light? Is it jumpy? I'ved used a cheap harbor freight adj timing light before. Or i just run timing tape on my balancer. You need to find the total timing, and when it comes in. Could be vacuum related. you can plug off the vac line and drive it around. see what happens
 
69signetv8 said:
In the past I have always had trouble timing the engine with a light and end up doing it by a vacume gauge and ear! If I use a light and try for a factory setting about 8/10* before the engine will die. I have a true TDC. When I use a vacume gauge and adjust the dist to get max vac she idles well and the performace seems good but pings bad. I've tried a few things as advancing or retarding the timing but she still pings. I use + gas 89 octine.

Although I've read other posts I'm not up on the "total" timing thing and not sure how to tweak outside from moving the dist back and forth!

Sould I start playing with the screw in the vacume can?? If so which way do I turn it and how much??

This is the stuff I hate:shaking:..Wish you were here!
Thanks
Click to expand...

Jimmy...with all the mods you have made to your engine, the factory settings are out-the-window now. You could just try backing the dist. up a little everytime you notice the engine pinging until it stops and leave the dist at that setting. Put a light on it to see where the new initial advance setting is ,and reset it to that number in the future.

I also agree with the quoted article...

" Carefully insert a 3/32" allen wrench into the fitting where the vaccum hose was connected to the vaccum advance canister. You will be able to feel the allen wrench go into an internal allen screw used to adjust the amount of advance provided by the canister. Be careful not to puncture the diaphram inside the canister. With the allen wrench plugged into the adjusting screw, turn the allen wrench 1/2 turn (180 degrees) clockwise to reduce the vaccum advance by approximately two to three degrees. Remove the allen wrench, reconnect the vaccum hose and rerun the part throttle test. Repeat this procedure until the detonation, surging and/or stumbling is eliminated. ""

This method will work if the previous method gets the initial advance too retarded for a decent idle.

Gimme a buzz if you want to get together and we can work on this.
 
69signetv8 said:
In the past I have always had trouble timing the engine with a light and end up doing it by a vacume gauge and ear! If I use a light and try for a factory setting about 8/10* before the engine will die. I have a true TDC. When I use a vacume gauge and adjust the dist to get max vac she idles well and the performace seems good but pings bad. I've tried a few things as advancing or retarding the timing but she still pings. I use + gas 89 octine.

Although I've read other posts I'm not up on the "total" timing thing and not sure how to tweak outside from moving the dist back and forth!

Sould I start playing with the screw in the vacume can?? If so which way do I turn it and how much??

This is the stuff I hate:shaking:..Wish you were here!
Thanks
Click to expand...

Jimmy:

Tweeking your vacuum canister won't help rid the ping.

Sounds to me your total timing, (excluding vacuum advance), is not enough and coming in to soon.

Your engine will run best at around 34* total @ around 2800 rpm. If it pings with your engine combo at this setting, then you dist needs to be recurved so your total timing doesn't come in so fast. I'll bet that your total timing is all in by around 1800 rpm.

Send your dist to Dave at FBO in Calgary. For about $100.00, you'll be glad you did. Once on his machine, he'll set the vac also. You should be able to run 15* initial and 19* mechanical= 34* total at 2800 rpm.

Don't run your engine if it's pinging that bad. You need buy or borrow a good timing light.

Keep us posted.

Jim

DSCN0830 (Small).JPG
 
Yup. I do agree I must do something. It's a real drag to spend cash for improvements (upgrades) just to end up with more problems. (One step foreward, and two back).
As I stated, if done by ear at idle and with (max) vacume then back off a tad she pings pretty bad, however performance isn't too bad. Maybe it could better! If I retard it just a tad to get rid of the ping she stumbles badly (out of time).
BTW, This is a problem I had some time ago that I posted. I rermarked TDC #1 compression. However, once the motor is running with timing light on, I have trouble finding TDC. If I turn the dist to try to get 8*-10* BTDC she wants to stall. I thought my damper was screwed, but then why would TDC line up on the scale.
So yah, somethings out to lunch. I agee with re-curving but to send something out just to find I still have a problem else where after spending more money will piss me off even more. I'm going to try the canister thing first as "what" can I loose.
 
Jimmy,
What kind of timing light are you using. If it is one with the adjuster dial, have a buddy rev the engine for you, slowly increasing it up to about 3200 rpm. Adjust the dial until your timing marks read 0 degrees. Then look on the adjuster dial, wherever it is reading is your total timing. Now rev the engine, slowly bring it up until your timing marks are reading 0 degrees again. The tach should give you the rpm that this happens at. This should be lower than the 3200 you used the first time. Whatever the rpm is, is the all in point of your timing. You should do this with the vacuum advance unplugged. I could be wrong but I don't believe the vacuum advance does much at WOT. I don't even have vacuum advance. Once you get these readings you can make adjustments with springs in the dizzy to get the best combo of timing for your engine. My 360 with 10.5 to 1 compression running 91 octane likes 16 init and 34 total, all in at 2500. That's with a Magnum 280 h comp cam.

Jack
 
Thanks Jack!! I guess this is the stuff I kinda hate. All the curving and figuring!! My last name seems to fit well with bad luck).....whatever I do, just seems to go a step back and more cash. I will have to invest in a better timing light as mine has no dial or readout. Perhaps I will need a new dist with a different curve as advancing or retarding just won't get rid of the ping.
Anything past 3000, and it go's like hell with no ping.
 
I'm gonna go for the simple/low buck answer here ... Have you tried an octane booster? Maybe 89 isnt enough for your motor.
 
Here`s another scenario;
1) Start with good gas , 91 octane at least if you`re over 9.5-1 cr
2) Disconnect vacuum hose and plug it
3) Measure 2 and 1/8" over from the mark on your harmonic balance and make a clear mark
4) Start the engine and bring it up to 3000 rpm
5) Time the engine so the mark you made on the balancer is at the 0 mark on your timing cover.
6) Return the engine to idle and reconnect your vacuum line. You should have a total timing of 34* without any vacuum in.
7) If the engine runs fine without spark knock you can try to go back to 89 octane. If it pings again stick with the better fuel.

You might check your timing light along a known good one, I have one that`s out 13*.Best of luck
 
Longgone said:
Here`s another scenario;
1) Start with good gas , 91 octane at least if you`re over 9.5-1 cr
2) Disconnect vacuum hose and plug it
3) Measure 2 and 1/8" over from the mark on your harmonic balance and make a clear mark
4) Start the engine and bring it up to 3000 rpm
5) Time the engine so the mark you made on the balancer is at the 0 mark on your timing cover.
6) Return the engine to idle and reconnect your vacuum line. You should have a total timing of 34* without any vacuum in.
7) If the engine runs fine without spark knock you can try to go back to 89 octane. If it pings again stick with the better fuel.

You might check your timing light along a known good one, I have one that`s out 13*.Best of luck
Click to expand...


Thanks Longgone, I'll give it a try! I completely understand your write-up. I just never thought "I" would need better then a Regular Plus Gas for my motor. I think i'm about 9.1 as the builder told me. BTW, Sure would like to be able to do a few strips like on your avator...
 
When our cars were built you could buy Sunoco 260 at the pump with an octane rating of 100, which at the time was considered premium. The low octane gas was around 91 octane which would still support 9-1 compression. Gas is pretty crappy today but cr`s are running as low as in the 7.s-1. Running a little better gas is an inexpensive way to avoid fuel related spark knock which can ruin an engine. You`ll get it right and be laying down tracks before you know it.:burnout:Let us know how it comes out!
 
Longgone,

That is a great way to get your total timing. I hadn't thought of that. The only problem would be the initial timing. If the dizzy is curved with say 28 mechanical timing that would only give you 6 degree's initial timing. In Jimmy's case that does not seam to be enough as the engine is stalling at 8 to 10 degrees of initial timing.

Jack
 
The main thing is to get the total timing around 34* and not to focus so much on initial timing. Most of the time our cars have been altered so much that a base timing is nothing more than a suggested starting point. If the mechanical is around 18-20 degrees then 14-16 would be your initial timing. Each degree on your damper is 1/16th" so you can use that as a guideline in what the base timing actually is ,once you`ve set the total timing at 34*. For running the streets you can employ your vacuum advance and that`ll make up for your timing advance before the mechanical is fully in. It`ll probably help with your gas mileage too! Under WOT you won`t have to worry with the vacuum advance as it`ll be out of the equation. I hope this helps some, I have a hard time explaining myself on the computer. If I was in Canada (wish I was today ,heat index here is at 105), I`d gladly come to your house and help you out. Good luck!
 
Longgone said:
If I was in Canada (wish I was today heat index is at 105), I gladly come to your house and help you out. Good luck!
Click to expand...

John, you'd have to go far north today. Here's our temp/heat index!

Currently 30 Celsius, Heat index> Feels like 43C or 109.4 F

From our Weather Channel.

Feels Like 43
Wind SW 22km/h
Relative Humidity 75%
Dewpoint 25°C
Pressure 100.73 kPa
Visibility 19.0 km
Ceiling 10000 ft

Updated:Tuesday August 7 2007,16:00 EDT - Windsor Airport
 
Woodys_Cuda said:
John, you'd have to go far north today. Here's our temp/heat index!

Currently 30 Celsius, Heat index> Feels like 43C or 109.4 F

From our Weather Channel.

Feels Like 43
Wind SW 22km/h
Relative Humidity 75%
Dewpoint 25°C
Pressure 100.73 kPa
Visibility 19.0 km
Ceiling 10000 ft

Updated:Tuesday August 7 2007,16:00 EDT - Windsor Airport
Click to expand...

75% humidity ,109 heat index, that`s awful, no wonder the polar bears are endangered! Global warming?
 
Jimmy,

I'm running into the same problem with my '68 Cuda 340 and was wondering if you got it rectified, and if so, what did the trick?
 
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