'93 block, 0630 head, stock valve train, stock '97 ecm, bosch 703 injectors (had ford blue injectors previously but ran rough with them)
I dont have a wideband, but have monitored long term fuel trims several times and its always been +/- 5%
I pulled both manifolds off last night as i'm installing a new header and making a 2.5" exhaust. Good time to look at the back side of the valves.
I noticed cylinders 1, 2, and 6 exhaust valves were brown/rusty/slightly damp and sooty ports as seen here
![Image](https://live.staticflickr.com/65535/50017753848_7617149475_b.jpg)
![Image](https://live.staticflickr.com/65535/50017753973_46bfd03511_b.jpg)
While cylinders 3, 4, and 5 exhaust valves were white and fairly clean ports as seen here
![Image](https://live.staticflickr.com/65535/50017753843_bd938cc1ec_b.jpg)
My old 150,000 mile motor that i pulled out has all 6 white exhaust valves. I figure thats what they should look like?
When I got the motor, I pulled the spark plugs that were in it (stock heat Autolites) and put in NGK ZFR6F11 as recommended here. I have maybe only 10-12 hours on these spark plugs. What would you say is going on with the wide variation in colors?
![Image](https://live.staticflickr.com/65535/50018281931_d7d26cc615_b.jpg)
![Image](https://live.staticflickr.com/65535/50018542992_9b40c04f47_b.jpg)
![Image](https://live.staticflickr.com/65535/50017753818_e49358759b_b.jpg)
![Image](https://live.staticflickr.com/65535/50017753788_f5c11501f8_b.jpg)
![Image](https://live.staticflickr.com/65535/50018281926_af67ca43fc_b.jpg)
![Image](https://live.staticflickr.com/65535/50018542987_9ed0679296_b.jpg)
Any help is greatly appreciated! Thank you!