This is my first time posting here, so let me describe the pertinent information of the build. B18B block B18C5 head B18C1 cams 22T water pump GSR timing belt TD68U distributor (OBD1 GSR) Engine #1 First time we started it, it idled perfectly and I was able to get the ignition timing correct by fully retarding the distributor. Later we found out the block was cracked and there was a leak in the head, so I tore it down and "fixed" the problem with the head. When I started it again, with the distributor fully retarded it was still not enough to get the ignition timing correct. Built a new engine with a fresh block and fresh head. Start it, and it idles around 100-250rpm with the distributor fully retarded. If I advance it at all, it won't start. I'm using the firewall mounted map sensor so that I didn't have to extend the wiring to reach the throttle body. Since it worked the first time I don't think it'd be the issue. There is only one vacuum line ran to anything, and that's the one from the firewall to the back of the intake manifold. The PCV port is blocked off because I'm running a catch can, and if I unblock it the idle jumps to 1000rpm but the ignition timing is off. If I give the car gas, it'll sound like it's misfiring then when I let off the gas it can't catch itself and dies. The distributor is newly remanufactured, and I've tried swapping a known-good ignition module and ignition coil. What I'm not understanding is why it worked fine the first time but will not now. With the timing light it seems like it's around 12-16 degrees too advanced. When checking the mechanical timing, when the cams are lined up, the tdc mark is maybe 2-4 degrees advanced, but I can turn the crank back so that it lines up without moving the cams. I'm considering retarding the cam gears a tooth and seeing if I will then be able to get the ignition timing set. Will this cause a performance loss? Any other suggestions?