Ok, if you've followed the 8psi milled head post here is an update. I got everything installed and now there is a problem at high rpm....from about 5500 rpm up. It starts bucking a popping out the exhaust, kind of like hitting the rev limiter but less extreme. I also can see black smoke coming out the exhaust. It seems like the ignition is cutting out. The air/fuel ratio guage stays in the rich, I adjusted the SAFC richer and leaner and made no difference. I believe it is an ignition problem, but I have a Crane capacitive discharge ignition, LX91 coil, MSD distributor cap, brand new NGK plugs (1 step colder), and Nology wires. The ignition has been on the car for 6 years, I'm wondering if the coil is getting tired? The only fuel related thing changed was the fuel pump, I installed the 255lph pump supplied with the Jackson boost upgrade kit (had a Walbro 190lph in before). I'm going to try and gap the plugs a little closer and see what happens? Any other ideas? Remember my compression ratio is approx. 10 to 1.....and I'm very confident it is not running lean. I've got a steady 75 psi of fuel pressure and also have the 310cc injectors. I'm open for suggestions.
Posts by crx-sc
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I've had the same cylinder head on the car for about 15K miles and I personally installed the headgasket (D16Z6 metal one) myself with ARP head studs. The motor does not burn oil. Hey man I thought you were a know it all, black smoke is fuel, blue smoke is oil. I'm dissapointed. 
It's running 35 psi fuel pressure at idle. Runs about 75 under full boost. The boost guage stays steady at 8psi. It's an autometer air/fuel ratio guage. I have played with the SAFC settings, leaned it out and richened it up in the high rpm and no difference. I am hearing a lot of bad things about the Nology spark plug wires so I'm going to swap those out and see what happens. Up until 5500 rpm it feels really strong now. I'll be having it dynoed within the next month or so probably.
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