My tpi has a zz4 cam. I've been using a bronze distributor gear the past few years without any problems. I recently pulled the dizzy and see that the gear has worn down to thin blades. Can I use the correct "melonized" gear, or am I stuck using the bronze gears forever due the wear pattern? I'm hoping that since the bronze gear is softer than the cam gear, no pattern has worn into the cam gear. Is this correct?

More trouble see post #7

 

The idea is to wear the dist. faster than the cam, so you should be good there. I'm using a composite one that seems to work quite well, and I believe Comp makes them.

 

You only need a bronze gear with a billet cam but you can also get a billet cam with a softer iron gear pressed on for use with a regular distributor gear.

If your camshaft doesn't recommend using a bronze gear, don't use it.

It's unlikely the teeth on the cam are worn.

 

Does the zz4 cam have a pressed on iron gear?

 

The ZZ4 camshaft is a GM hydraulic cam, so it would use the same type of gear as the fatory hydraulic cam... IMO

 

Wow, you guys are fast. So I should be safe using the GM gear. I was just worried that a pattern was worn into the cam gear when I used the broze gear. GM gear on order thru Pace.

Once again, thanks for the help everyone.

 

More trouble. I put the new gear on and now I can't get it to start. I flipped it around 180 degrees, I turned the crank over to see exactly which cylinder is at bat. I've moved the dist a little each way just in case the timing is off. It's turning over but not catching. Is there something I lost when I r&r the gear? Just above the gear is a shim and a tooth piece. There is a collar that surrounds the rotor that when turned clicks into position and can be turned back into another position. I can't find anything on this collar.

I have the small cap distributor with remore coil for a 92 tpi.

 

Without knowing exactly what you've done...

Take the cap off the distributor so that you can see the rotor. Remove the #1 spark plug. Bar the engine over until the #1 cylinder is at TDC. The easiest way to do this is to put your thumb over the spark plug hole. As the piston comes up on compression stroke, you'll feel the air escaping. Another method is to stuff a paper towel in the hole. As the compression starts, it will get blown out of the hole.

You can also remove the rocker cover and watch the rockers.

As you notice the piston is coming up to TDC, watch the timing mark on the balancer. Keep rotating until it lines up with the timing pointer. It doesn't have to be 100% accurate but within at least 10*.

The rotor in the distributor should now be pointing to the #1 plug wire. If it isn't, you'll have to pull the distributor and turn it. You may have to turn the oil pump drive also to get the distributor to drop all the way in.

It's easy to pull the distributor without seeing where the rotor is pointing first then dropping it back in with the rotor in a different position.

Assuming that's all correct, is the rotor under the cap? Is the distributor and coil plugged in? Are the wires inside the distributor plugged in?

 

It was 45 degrees wrong. Thanks Stephen. I watched the lifters open and close for the #5 cylinder. So I figured I'd aim the rotor to the #5 pole on the cap. It still must been off. With your way of testing, the paper blew out about 90 degrees before 0 on the balancer. I was aiming at the wrong cylinder this whole time.

 

So did it fire up yet?

 

Yep fired right up. I set the timing and drove it 15 miles to work. Thanks again.