i recently had a 94 lt1 rebuilt. I told the engine builder that i was going to put it into a 96 z28 and convert it to OBDI since the tuning would be easier. The engine is completely done and waiting to be put in. I spoke to the guy that was tuning the car for me and he said that it would be better to just put all the 96 stuff onto the 94 motor and stick with the OBDII system. so i began putting all the 96 stuff onto the 94 motor. as i was swapping the opti i noticed that they were completely different. There is a tone ring on the 96 block and there is not one on the 94 block. is this something that can be put onto the 94 block? this seems to be the only thing slipping me up at this point. any help is appreciated.

 

If you are truly making it into OBD-II (I really would have stayed with OBD-I), you will need to add the reluctor ring behind the crank gear. You will also need the 96+ crank gear woodruff key, plus the 96+ timing cover for the crank sensor that goes in it. You will also need the knock sensor that goes with the 96+ computer.

 

is all that stuff on the 96 motor? I just pulled the 96 motor out of the car on sunday and it ran fine. if it is what is what? and how do i go about removing them?

 

Yeah, all that stuff should be there. If you have a done 94, I don't know why you would go through the trouble. Your tuner should be able to handle it either way.

Oh, you will also need to use the 96+ crank hub if you put the reluctor on.

 

the 94 block has been completely rebuilt with a all forged bottom end, bored 30 over, with 2.02 valve heads, over all it has 11 to 1 compression. the reason i am going with the OBDII set up is because my tuner does not have the software for OBDI and i get a pretty good discount on tuning with him. around 200 for everything and thats a dyno tune. is it possible to take all these parts off the 96 block by just removing the timing cover? thanks for your help.

 

i found the ring. but how do i remove the key? and what is the crank hub?thanks for your help

 

The reluctor gear behind the crank hub is for the crank position (CKP) sensor. That sensor is ONLY used for OBD-II misfire detection. You bargain tuner should be able to "tune out" the CKP sensor so it doesn't set the codes for a faulty sensor. The CKP sensor does not affect the way the engine runs.

The knock sensor has to be changed, because using a 4,000 ohm 93-95 sensor with a 96/97 OBD-II PCM results in a mismatch, since the 96/97 sensor is 100,000 ohms. Run with the 4,000 ohm sensor and you will get a code for the knock sensor, and large amounts of knock retard.

 

so the knock sensor is one on the 96 timing cover? also i am not sure what the crank hub is.

 

The knock sensor is in the hole for the block drain plug, right next to the passenger side motor mount.

All links courtesy of Shoebox:

http://shbox.com/1/ks.jpg

You don't need to screw around with the reluctor gear. But if you insist on doing it, the damper/pulley on the front of the crank comes off. That leaves you with the crank hub, with three bolt hole in it. There is a center bolt that holds the crank hub on the snout of the crank. If you pull the hub off (requires a strong "puller), and the Opti and the water pump, you can remove the timing cover. That exposes the reluctor gear which just pulls off, Then you have to remove the timing chain, so the crank sprocket can be moved forward to expose the key that holds the crank sprocket and reluctor gear in position.

http://shbox.com/ci/balancer_hub.jpg

http://shbox.com/1/hub.jpg

http://shbox.com/1/pull_pulley.jpg

Reluctor gear is not shown, because this is a diagram from the 95 manual.

http://shbox.com/ci/front_cover.jpg

http://shbox.com/ci/sprockets.jpg

The CKP sensor is the sensor that is mounted on the bottom left (as you look at the engine from the front) of the timing cover.

 

thank you for all that information. it is very helpful. so just to clarify. I dont need to worry about the ring? it does not look(to me but i dont know much)like the 96 distributor will not work without it. or is it just there to work that senor? sorry for all the questions. my engine builder is out of town for a couple weeks.