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Has anyone ever had to....

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L

lesingepsycho

Jedi Warrior
Offline
...shim the balancer out? Here's my situation:
I'm setting up this engine to use a 36-1 crank trigger and (probably) a Ford EDIS ignition controlled by my Megasquirt box.

The PROBLEM is that the way the 36-1 tooth wheel is bolted onto the <span style="font-style: italic">back </span> of the balancer it is going to rub on the timing cover.

The SOLUTION seems to be to make a shim or spacer to go against the oil slinger and shim out the balancer <span style="font-style: italic"><span style="font-weight: bold">just enough </span></span>to get clearance to the timing cover. We're talking about .125" or less.

Anyone see a problem with this??

JACK
 
Not me.
 
MS ehhh???? I've been thinking about that route too. I've had a kit in the desk drawer for about 4 years now.
 
I mounted my toothed wheel on the front of the balancer. I sectioned the steering rack mount, reducing it's front-rear dimension some 3/8" to get clearance. Plus: allows pulleys to run in the same plane as before. Minus: Have to remove the pickup to replace the fan belt - but a new belt does last a long time. I can't figure out how to show photos on this site, if you send me your email I can email a couple of shots that show the setup, more or less. I'm running only megajolt at the moment, still trying to figure out how much of a hp boost I'd get switching to a Squirt.
 
OK, so here's some pics of today's progress. I went to the local (TRUE old fashioned) hardware store and found some machine bushings that were the exact sizes I needed. A little modification to fit the keyway and I was in business. I bought 5 bushings ranging in size from .050 to .150 and wound up using a combination of 2 to get the exact clearance that I wanted between the crank trigger and oil seal on the chain cover.
 

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It's about .035 clearance.
 

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Would it have been easier to remove the key?

Steve
 
I am not familiar with what is supplied with either MegaJolt or MegaSquirt so this is question may sound naive but I'm curious.

You have a toothed pulse wheel and obviously some form of pickup. Could you not modify the insides of a stock distributor and mount the pickup inside? You'd need to fix the breaker plate and disable the bob weights (obviously). And the gear in the dizzy would be turning at 1/2 engine speed which would mean either making a wheel with twice as many (smaller) teeth... but would it not be "doable"? Or... do you tell the controller how many pulses there are per engine revolution... so you could get by with a smaller wheel with fewer teeth? Or... if you can tell the controller how many pulses there are per revolution, could you not count the ring gear teeth on the flywheel? (Or is this a non-starter because one tooth has to be different to be identified as TDC?)

I'm not really interested in doing this to one of my cars and I don't want to drag your thread off course. However, I am a little curious about what level of customization you can easily incorporate into the system.
 
The Megasquirt system allows for just about ANY timing input; standard points, breakerless ignition, hall effect, optical, variable reluctance, cam sensor, etc. You are correct though in thinking that the breaker plate of a distributor has to be "locked down" with all mechanical and vacuum advance functions removed or disabled. This makes perfect sense as the computer would not be able to sense or know how the advance was affecting the spark timing. In effect you need a steady signal which acts more as a positional indicator than a timing device. At that point, the dizzy's only function is to direct the spark to the appropriate cylinder but all the timing and firing of the secondary side (coil) is done by the Megasquirt system with all the timing maps programmed in and variable according to RPM, Load, Coolant Temp, Ambient Air Temp, O2 reading, etc.

In fact, right now I'm running Pertronix's Flamethrower II distributor and if I wanted to, I could keep it for use in the Megasquirt system. This diz probably only has 1000 miles on it but I'm switching to the crank trigger and Distributorless Ignition System (DIS) just for the fun and excitement and adventure of it! :banana:

JACK
 
Steve,

We're talking about the crankshaft woodruff key that holds the crankshaft timing sprocket in position so removing it is not really an option. I also really liked the idea of having my shim keyed to the crank as well because I didn't like the idea of it slipping around in between the balancer and oil slinger and causing a bunch of metal filings getting in the oil.

JACK
 

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Got it!

Glad to see there is enough room to have the 710 seal work too. Might even be better now that it has a new area to 'groove'.

Enjoying the updates, keep it up.

Steve
 
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