After info on fitting a msd crank trigger to a 360 magnum & working out t pulleys

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maca

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hi guys
Since I rebuilt my engine I can not get a stable timing mark. Its all over the place. It was rock solid when I ran a hydraulic cam with low spring pressures but now I am running a solid roller cam with bigger spring pressures it moves around at all rpms
[ame="https://www.youtube.com/watch?v=ky4e5Hso7Ro&feature=youtu.be"]Moving timing mark - YouTube[/ame]
I watched a video about a MSd crank trigger and it looks like a great way to get solid stable timing. The only thing is its 3/8 of an inch thick which means it will push out the crank pulley the same amount. I don't want to have to space all my accessories out too so is there a lower profile crank pulley I can use?
cheers Maca
 
How much up & down play is there between the intermediate drive gear/shaft and the distributor? On my big block, I had to add a collar to the distributor shaft to keep the intermediate gear from moving up and down too much. Before adding the collar, the driven gear/intermediate shaft would ride up and down on the cam's drive gear causing accelerated wear on my bronze gear and allow the timing to move around like you are describing. The collar eliminated the intermediate shaft's excess up and down play, stabilized the timing and reduced the wear on my bronze driven gear.
 
Sounds like an expensive way to fix a simple problem. If your timing is jumping around, I would look at distributor shaft slop, both up/down and bushing. If its good, I would check timing chain. If thats new, then you have a bad damper or ignition box. Unless you are running 800hp or some serious timing related fueling system as in juice or boost, a good distributor, properly tuned and a good box/wires/coil should be all you need. If its anything but distributor, the crank trigger wont solve problem anyway.
 
I am currently running around 550fwhp and about to up boost once I sort out the timing. Not sure if hp is the cause here or not.
I would love to fix it rather than a crank trigger but running out of ideas as this dizzy and shaft etc all worked fine on my last engine.
Last night I bypassed my msd programmable ignition box and it was still moving.
So if I discount the ignition box that leaves the dizzy area and timing chain.

How do I check timing chain without stripping the engine. Do I move the balancer back and forward and look in the dizzy hole to see if the cam is moving?

I think i will try another dizzy as my msd one looks fine. How do I check the up and down play and where does the collar sit? There is some side to side rotor movement as the dizzy just fits into a slot in the shaft. .not a gear.
Thanks
 
check for slop in any of the areas it could occur, crank to cam probably not, specially under load, cam to distributor gear or shaft/gear wear yes. Module, yes...what about sticking weights? My guess is either distributor or electronics rather than gear related as any slop in gears/chain will go away when its all wrapped up with tension on everything, if it only did it on decel, I would look at chain or cam gear/oil pump drive.
 
Hey John
Where does the collar go and how do you measure the up and down play? Both the gear and cam are brand new and look to have no ware but I did have to replace the press on gear when I built the engine. Perhaps I pressed it into the wrong spot and have a lot of up and down movement as you say. When I pressed the new gear on I measured the old one from the bottom of the intermediate shaft where it goes into the oil pump and up to the bottom of the gear to make sure the shaft went into the oil pump the same amount as the last one. I am now thinking that I should have measured from the top of the gear to the top of the shaft. I will measure the thickness of the old and new gear to see if there is a difference.

Hey Magnummopar
It does still move under load as I put the car in gear and stalled it up to its max stall of 2800 and it still moved around. So you think if its moving under load its probably not the timing chain? The dizzy is locked so the weights are gone. I am still getting my hands on a borrowed dizzy to try. Here is the movement in the gears. Only very small movement.
The dizzy however has a lot of play but I think its just because of the slot set up instaed of a gear set up on the bottom of the dizzy. maybe someone on this site can tell me if they have the same moment. Here is a couple of videos.
[ame="https://www.youtube.com/watch?v=RMfqaEUUBgQ"]Oil drive gear slop - YouTube[/ame]

[ame="https://www.youtube.com/watch?v=h8_fqMh4Jas"]Dizzy play - YouTube[/ame]
 
What you do is install the collar on the bottom of the shaft (just above "slot") and tighten it just enough to where it will stay in place on the shaft, but can still be moved fair easily. Do not make it too tight or it will not move during the next step. Also, go ahead and put loctite on the set screw at this time. Once the collar is in place, install the distributor in the motor and tighten it all the way down. The collar will slide into the correct position. Then all you need to do is pull the distributor, tighten the set screw, and reinstall.

I robbed the photo off this site
 

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gtsdude said:
What you do is install the collar on the bottom of the shaft (just above "slot") and tighten it just enough to where it will stay in place on the shaft, but can still be moved fair easily. Do not make it too tight or it will not move during the next step. Also, go ahead and put loctite on the set screw at this time. Once the collar is in place, install the distributor in the motor and tighten it all the way down. The collar will slide into the correct position. Then all you need to do is pull the distributor, tighten the set screw, and reinstall.

I robbed the photo off this site
Click to expand...
That's an excellent pic. Thanks
Can I buy the collars from msd etc or do I just hunt around at engineering shops etc
cheers
 
I checked the timing chain and its fine which I am very happy about.
I pulled the dizzy apart and may have found something. It looks like water or moisture may have gotten in at some stage.
The sensor looks a little rusty. Can I sand it clean or do I need another one?
 
I sure would,rust could have made its way into epoxy where wires are. That bearing looks like it might need to be dealt with as well. might just be rust stain from pick up or not...
 

The bearing is fine. Its just the spacer washers that look bad.
I sanded it clean and tried it again. It seemed a little better but far from being solid. I will buy a new one tomorrow and try it over the weekend.
thanks for the help
 
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