fresh 95 motor questions

Finished the rebuild of my 95 sc motor with the following. standard crank, ..030 pistons, total seal rings, comp cam 210/220-.498, new plugs and magnacore wires, Felpro all the way, ported 94 supercharger, heads and intake. My problem is as follows. When I first got the car the tach was erratic and finally quit...bought the car from this board it was the blue one from Indiana for sale about 9 months ago...and the motor was running but very poorly. A teardown revealed 3 cracked pistons and thus the full rebuild. The rebuild and install went well. I degreed the cam per the cam card to within 1 degree.... it was retarded by one degree. The startup was fine, it fired right away...and I had primed the oil pump. Cold idle is very smooth. but when it warms up and comes off cold idle it lopes...go figure...well it does have a cam right! The problem is it does not want to stay running in gear (it's an auto) and stumbles bad off idle. The good is that when it hits 2000 rpm it absolutely will pin you in your seat like no other SC I have had before. The tach still does not work, so I replaced the cam sensor with one off another SC engine I had that had been running. Still no tach and still stumbled. It may need a bit of EEC work to soothe the savage beast, but what do you guy's think about the tach. I have seen several references to the crank sensor and ignition module. I have a spare harness and several coil packs thought I may try those as well. Thanks in advance, you guys are great resources.

Marc in North Carolina

If I remember correctly, DIS module, cam sensor, and bad ground are the only things that mess up the tach. For me it was the DIS module. I used Dielectric grease instead of Heat sink compound and it messed everything up. All I did to fix the problem was clean the dielectric grease off and put the heat sink compound on and unnecessarily bought 4 new screws from ACE Hardware.

I also have an untuned cammed SC that runs normal when cold then starts loping when warmed up.

Congrats with the rebuild and good luck.

A problem I had was a capacitive discharge for the coil pack had become lost. Its a little capacitor that attaches to the corner of the coil pack. Mine was gone, and it was arcing and when it did that apparently it interrupted the SPOUT signal because my Tach would drop to 0, and sometimes stay there. Maybe something to check out.