Rwillia4 Rob from my 30+ years of beening under the hood I have learned this. Each company has there own spark plug builders. GM has AC. Ford has Autolite. AMC used autolite or champion or what ever they could find. What ever year the motor and heads are based on start there. You are not racing all the time and not going from sea level to 5,000 ft every day so your heat range will only go up or down 1-2 levels max. I would go back to what ever the motor started with. Is this a KCR motor? KCR would put the plugs to match this motor to start or maybe 1 range warmer.
A poorly programmed FI system will kill a set of plugs and O2 sensor in 5 minutes. Yes I know this from my own setup. Fast asked for info on my motor and sent me an ECU with firing orders for plugs and injectors for a BBC setup. My motor ran with everything 180 off degrees. Cooked the paint on the car in 45 seconds. I went to Second Street in PA. I forget owners name but took 7 hours, 8 phone calls and a electical diagram to correct THEIR screwup. 2 sets of plugs and 1 O2 sensor for the car, an $500.00 O2 for the dyno also got screwed in the deal. It's amazing how it's never anyone fault.
I have the DVD on the fast programming and read the info on my system. The bottom line for any motor with FI is to have the 1st programming done on a dyno and spend the 2-400.00 dollars. What comes from this is a good base line to start. You put this on a floppy disc (in my case) or down load on a hard drive that can't crash. If lost, reboot and start from there again. Some guys run motors lean and mean. You make the most HP. Here's the rub, I want torque and couldn't care about HP. My motor lives between idle and 6,200 rpms period. FE's cost 1/3-1/2 more to build than Lima or windsor motors. I don't have deep pockets either. I have my motor setup soft on the tune because of where I go in the country to run. IMO running a little soft will never hurt a motor. 15 years with same block and started with a 452 and now run a 482 shelby motor. A 20K motor being or getting cooked is not worth a $12.00 piece of press board and plack with what place you ended up,(award). Back to you,
If this was my problem, the motor is carboned out this is where I would start
First thing is to decarbon motor, GM sells top engine cleaner. Nasty stuff will take the paint right off the car if dripped on. I have a throttle body on my motor so a slow pour works for me. Let sit for 20 minutes and start motor. Let motor warm up at 1,500 rpms and clean out. In your case easiest thing would be to buy a spray bottle and add a mixture of distilled water and washer solvent and spray into a warm motor. The mixture turns to steam and help remove the build up. Lite spray you want and to hear the motor drop only 100-200 rpms MAX. You pour water into motor and you may lock it up and bend rods. This will not effect the
oil spark plugs or O2 sensor. After this is done, new spark plugs and O2 sensor. It's hard to find a qualified dyno shop that KNOWS the FAST and SPEED PRO system and how and what to do for setups. My guy wanted to know everything about my motor and this makes good sense to me. Other guys don't ask a thing and car and motor never run right. You can tell by the seat of your pants when car is running good. Buying an A/F meter might not be a bad idea either and mount it either in both banks or other bank O2 sensor is not in. Not sure how goo the A/F meter work with the ones sticking into the end of the tail pipe or side pipe, fresh air issues. If plugs are black it means that you are running rich and the motor never leans out or
oil is being sucked into the intake side of the motor and being burnt. Only way to know this
oil problem is to watch your level. If you are going through a quart of oil every 1k miles, AGAIN IMO, you have a sealing problem or real heavy abuse issue. Blue smoke on startups is oil, Black smoke is running rich. White smoke, cold moisture in exhaust is OK, Motor hot and running for 15 minutes, coolant problem like blown head gasket. This does keep bugs away from you.
New plugs and O2 and recheck programming of ECU. I would run autolites. NGK's are for turbo motors, or for motor across the pond or motorcycles. NGK's remind me of Champions, run great for 1-5 hours, after that so-so. Late note I do cut back the bridge on the plugs and have set them up so the spark is shooting at the intake valve. They call it indexing and takes time and thin washers. Not worth the time for your motor. Good Luck Rick L.