crank trigger

SDMAN · 01-08-10, 06:49PM

We are sending my ATI dampener back to get their built in magnet ring put on it. I have no experience with crank triggers on anything, and it occurs to me that the placement of the magnets (in degrees) is likely important. Do I need to spec this or is it pretty much the same for any crank trigger setup?

I will be using a FAST XF-I EFI computer, coil on plug setup with a cam position sensor built into the oil pump drive.

Gach · 01-08-10, 07:53PM

What kind of Crank Tiger did you get ? I have the MSD Tiger, and already has the placement of magnets ( in degrees ) on the wheel that bolts to the balancer. It's real easy to set up to. They make a real nice set up for
Pontiac's

tiacguy · 01-08-10, 11:07PM

Can I ask whos oil pump drive. I cant find one for a Pontiac with a cam sensor. Im looking to do this also. Thanks for the help Scott.

Pontiac Jack · 01-09-10, 03:08AM

Quote:

Originally Posted by SDMAN

... Do I need to spec this...

Only if you're very limited in selecting a location for the pickup. If there's any spot around the balancer that allows you 90 degrees of freedom for pickup placement, then orientation of the magnet wheel won't matter (magnet every 90 degrees).

Has the choice of a pickup already been made? I prefer a Hall-effect pickup, just because setup and maintenance is much "nicer". A Hall-effect transistor is a static device, unlike a pickup coil which requires magnet velocity to generate a signal. This means that it can be precisely set with the engine at a standstill. The Crane pickup that I'm using has an LED built into it, making setup a breeze. For instance, I rotated my crank to 37` BTC, then simply moved the pickup CCW in its mounting slots until the LED extinquished, and tightened the mounting screws.

SDMAN · 01-12-10, 03:09PM

Quote:

Originally Posted by tiacguy

Can I ask whos oil pump drive. I cant find one for a Pontiac with a cam sensor. Im looking to do this also. Thanks for the help Scott.

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Im using a BOP part that they supply with their front mount distributor. We are modifying it to also work as a cam position sensor. Call Wade at BOP. He will set you up.

tiacguy · 01-12-10, 07:52PM

SDMAN Thankyou very much. Keep us posted on your progress please. Scott.

SDMAN · 01-14-10, 12:15PM

Quote:

Originally Posted by Pontiac Jack

Only if you're very limited in selecting a location for the pickup. If there's any spot around the balancer that allows you 90 degrees of freedom for pickup placement, then orientation of the magnet wheel won't matter (magnet every 90 degrees).

Has the choice of a pickup already been made? I prefer a Hall-effect pickup, just because setup and maintenance is much "nicer". A Hall-effect transistor is a static device, unlike a pickup coil which requires magnet velocity to generate a signal. This means that it can be precisely set with the engine at a standstill. The Crane pickup that I'm using has an LED built into it, making setup a breeze. For instance, I rotated my crank to 37` BTC, then simply moved the pickup CCW in its mounting slots until the LED extinquished, and tightened the mounting screws.

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Good input. Ill look into the hall-effect pickup. I like the setup you describe. Sounds quick and easy.

tiacguy · 01-14-10, 05:43PM

SDMAN Can I ask what cam sensor your going to use? I found a pic of the BOP pump drive but I cant see the top of it. I cant tell what its going to take to modify it for a cam sensor? Thanks scott.

SDMAN · 02-26-10, 09:54PM

Sorry. Been tied up with work and other 'stuff'. The cam drive from BOP is pretty much only a cam drive. We plan on modifying the top of the housing to incorporate some type of pickup. We simply havent gotten to this point as yet, so specifics arent known. I bought it because it was a good starting point.

Ollie · 09-21-10, 02:36PM

I have AutoCAD drawings of what I think is an effective Pontiac oil pump drive - cam position sensor.
I also have 36-1 trigger Wheels to fit the Pontiac harmonic balancer. The trigger wheel bolts to the back side of the balancer so the belt alignment is not affected. I also have drawings for mounting the trigger wheel sensor.

twinturrbo406 · 09-28-10, 08:29PM

Quote:

Originally Posted by Ollie

I have AutoCAD drawings of what I think is an effective Pontiac oil pump drive - cam position sensor.
I also have 36-1 trigger Wheels to fit the Pontiac harmonic balancer. The trigger wheel bolts to the back side of the balancer so the belt alignment is not affected. I also have drawings for mounting the trigger wheel sensor.

....... i know that Accel makes a Dual-Sync distributor for SBC's, which basically has two pickups in it, one is used for the cam phase signal, does MSD make a distributor like this ?? If so, i'm sure the guts would bolt into a Pontiac MSD Pro-Billet Distr. ????

Ollie · 10-29-10, 12:18PM

This is my own design, using the lower part of an Accel duel point distributor and a CNC machined top to use either a magnetic MSD or a Mallory Unilite module.

SDMAN · 10-29-10, 11:20PM

Quote:

Originally Posted by twinturrbo406

....... i know that Accel makes a Dual-Sync distributor for SBC's, which basically has two pickups in it, one is used for the cam phase signal, does MSD make a distributor like this ?? If so, i'm sure the guts would bolt into a Pontiac MSD Pro-Billet Distr. ????

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I planned from day 1 to use a coil on plug setup, and eliminate the distributor completely. The oil pump drive doesnt have any parts above the distributor clamp. That allowed us to push the motor back as far as possible, which we did. So anything distributor based will not work in my application. The 4 red MSD coils on each valve cover really changes the look of the engine.

Ollie · 10-31-10, 11:09AM

A cam position sensor is required for sequential Ignition and fuel injection. The only other way to operate the ignition is wasted spark with an EDIS module and batch fire the injectors.

Bruce Wilkie · 11-28-10, 02:18PM

Hows this coming along? A cam position sensor only needs to serve as a "home" position to reset the sequence clocking. In fact you need not sense the CAM at all, you can clock from crank with a small belt drive or any other method to get to 1/2 speed of crank if you wanted to. The most common method is simply a metal flag on the cams timing gear with a mag pickup through the timing cover. Because it only needs to serve as a reset point the timing isnt as critical as the start of sequence timing off the crank.

A mag sensor is accurate enough(plus not affected by oil) for this purpose. Chain stretch can be compensated thru detection/correction software that compares home position of crank time to actual reset time and adjust sequence time accordingly. Dont know if any EFI controller has it, but the technology exists. An educated guess tells me "missing tooth" crank trigger wheels allow for this detection/compensation. (I really do need to get up to speed on current efi software tech) Missing tooth would allow a window for reset to occur before sequence clocking begins again, keeping everything in sync.