ulakovic22

Ok, guys, I'm not sure how Advanced Tech this is, but hopefully I'll get some response.

On my BBC project I'm running fuel injection. I have a crank trigger for the crank signal and a dist. modified for a cam signal (MSD 2340). You have to tell the computer when the crank and cam signals are going to happen so it knows what cylinder it's on. To phase in the cam signal you need to line up the magnet and pick up and stab the distributor approx. 65 BTDC. Then you rotate to your time setting for max power, approx. 35*. At 35* the distributor rotor needs to be lined up with a terminal on your cap and that terminal will become #1. When they don't line up you need to "phase" the rotor.

For me it means that you have to move the rotor without moving the base. For a std. distributor you would modify the reluctor. In any case the MSD adjustable rotor won't fit in my distributor so I'm stuck modifying the fixed rotor. To make the fixed rotor adjustable I have to elongate the holes and remove to "keys" that line the rotor onto the base.

One of these "keys" used to orientate the rotor on the base doubles as the mounting base for the screw that attaches the brass tip to the rotor. When I cut the nipple off I will be shortening the screw as well. If the screw still won't clear the base I will have to find away to mount the rotor tip to the rotor. Is there any kind of epoxy or glue that I could use that would hold up to the high voltage in the dist.?

MachinistOne

In crank trigger applications the distributor is not adjusted to change your timing numbers so to phase the rotor you simply turn the housing to line it up properly with the cap.

What am I missing? Why does the housing have to stay in that fixed position?


MSD's tech forum would be a good place for this post, the few times I have done crank trigger ignitions it was as straight forward as my first comment.

ulakovic22

I'm not sure what you are missing because this is the first time I have done this, so I don't have anything to compare it to. The magnet and pickup for the cam signal in the dist. have to be lined up between 60-70* BTDC and then you rotate the motor over to timing at max power (35*). 35* is when the rotor and cap should be lined up so you don't get your spark jumping around or going to a different terminal all together.

I can't phase the rotor at 35* because the BS3 says the cam signal needs to occur between 10-20* before your crank signal, which for me is 50* BTDC. If I phase the rotor at 35* and rotate the engine back until the magnet/pickup for the cam signal align the cam signal will be less than 10* before the crank signal and I'll get a sam sync error. I need to move the rotor counter clockwise about the width of the rotor tip (<10*) so it will be lined up at peak power and the magnet/pickup will be lined up between 60-70* BTDC.

Edit: The housing holds the pickup and the black base pictured above holds the magnet. If I phase the rotor and move the housing I will be moving the pickup as well, which will effect their alignment between 60-70*.

MachinistOne

I get it now - you need the magnetic pickup and reluctor to be timed for the EFI system, I have not set them up that way. I now get what your problem is an found this article describing clocking the reluctor in order to get around this problem where an adjustable rotor does not work...

http://www.candbmotorsports.com/camsync.html