340 TIMING MARK
08-16-2012, 06:54 PM
#1
New Member
Thread Starter
340 TIMING MARK
I have a 340 1970 cuda, the engine has a cam in it and I have no spec. on the engine. The problem is the timing mark is so far off and is about 2-3" advanced I think it is to the right of TDC if you are looking at it from the the front. The cars runs ok put I dont no how to tell if it is to advance. The timming mark also bounces up and down on the scale and is not steady at all. I removed the vac advance be for chicking the timming. The car smells from fuel when it is idling.
Any help would be great
thanks in advance
Any help would be great
thanks in advance
08-16-2012, 07:47 PM
#2
The only practical way to check or remark TDC is with a "piston stop," which you can make or buy:
http://www.jerrybramlett.net/images/...stallation.jpg
Remove the no1 plug, and make sure the piston is "down some." Remove the battery ground for safety
Install the device. You may have to adjust the length the first time you use it. It is important that the stem be rigid and locked in place so it cannot move
Rotate the engine using a socket on the front bolt, until the engine stops on the device. You are not trying to stop the engine at TDC, but rather with the piston down in the bore somewhat. Distance is not all that important. When you get it stopped, carefully make a mark under TDC on the timing tab onto the balancer
Now do the very same thing going CCW. When you get done, you will have TWO marks on the balancer. True TDC is halfway in between, and if the original is accurate, that is where it will be
It is a wise idea to mark the balancer for checking advance degrees, or buy the proper timing tape for the size of the balancer
To mark the balancer does not need to be "all" that difficult. Use a small flexible tape and carefully measure all the way around the balancer, accurately.
Now use some math and figure how many "degrees per inch"
Now measure off 40* by using your tape (do NOT use dividers for this measurement) and mark that off. Use a small square and scribe
Next, use dividers and divide the 40* mark in half for 20, half again for 10. While you are at it, add marks out to 50 or maybe even 55 so you can check the vacuum can.
http://www.jerrybramlett.net/images/...stallation.jpg
Remove the no1 plug, and make sure the piston is "down some." Remove the battery ground for safety
Install the device. You may have to adjust the length the first time you use it. It is important that the stem be rigid and locked in place so it cannot move
Rotate the engine using a socket on the front bolt, until the engine stops on the device. You are not trying to stop the engine at TDC, but rather with the piston down in the bore somewhat. Distance is not all that important. When you get it stopped, carefully make a mark under TDC on the timing tab onto the balancer
Now do the very same thing going CCW. When you get done, you will have TWO marks on the balancer. True TDC is halfway in between, and if the original is accurate, that is where it will be
It is a wise idea to mark the balancer for checking advance degrees, or buy the proper timing tape for the size of the balancer
To mark the balancer does not need to be "all" that difficult. Use a small flexible tape and carefully measure all the way around the balancer, accurately.
Now use some math and figure how many "degrees per inch"
Now measure off 40* by using your tape (do NOT use dividers for this measurement) and mark that off. Use a small square and scribe
Next, use dividers and divide the 40* mark in half for 20, half again for 10. While you are at it, add marks out to 50 or maybe even 55 so you can check the vacuum can.
The following 2 users liked this post by 440roadrunner:
Gorts 5th (08-17-2012),
gregsgs@yahoo.com (08-17-2012)
08-17-2012, 05:09 PM
#4
Mopar Lover
the mark you are asking about is that the rpm at the tac and or the timing test instrument
ive got a fairly large cam in my 318 and at idle there is a slight variation.......... in gear there is a large variation
my combo doesn't like a lot of initial advance i use the programmed vacuum port on the carb and a duel spring rate at the distributor, mallory and yes i get that gasoline smell or rich smell at idle but if i lean out the idle circuit the transfer from off idle to primary metering will cause a lean miss fire or poping out the tail pipe and a hesitation the price i pay for the cam i choose but once off idle the mix leans out and she runs and runs well
you might try experimenting with your timing
my combo works real nice
ive got a fairly large cam in my 318 and at idle there is a slight variation.......... in gear there is a large variation
my combo doesn't like a lot of initial advance i use the programmed vacuum port on the carb and a duel spring rate at the distributor, mallory and yes i get that gasoline smell or rich smell at idle but if i lean out the idle circuit the transfer from off idle to primary metering will cause a lean miss fire or poping out the tail pipe and a hesitation the price i pay for the cam i choose but once off idle the mix leans out and she runs and runs well
you might try experimenting with your timing
my combo works real nice
08-17-2012, 06:14 PM
#5
New Member
Thread Starter
Someone put a silver line on the pully and I have checked the timming with a timming light the line on the pully moves up and down by 1" or more. The car starts up on the first try and runs well no mis no noise from the engine. I am going to get a piston stop and my son and I will try to get the timming. If any one knows of some one that works on mopars in north jersey let me know. I am not to good with cars the way I was 45 yrs ago the hands and eye dont work so well. Thanks to you all.
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