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This is a pic of one of my plugs. I haven't been driving the car, just running it on jack stands through my drivetrain and everything. I don't just let it sit and idle the whole time, I usually hold it up around 1500 to keep the oil moving good.
This plug looks different on each side, one side leads me to believe it is lean, the other looks correct.
What do you guys think about this?
Is it pointless to try and read plugs when the car isn't being driven?
forgot this
other side
Definitely a lean idle. Can't really tell more until the engine is under a load. Without a load the carburetor can't deliver ample amounts. Richen up that idle some.
~Ty@TLI/TPC
make a mark on it?
with what?
What Denny is explaining is indexing the plugs. It's one of the tricks of blueprinting a motor. With flat-top pistons, you want the open side of the plug electrode pointing to the center of the cylinder. If you do this on all the plugs, you will optimize the flame path across the chamber and equalize all the cylinders. Using a black felt tip marker, mark on the porcelain where the opening is, so that you can look at the plug once it's in the motor and see where the open side is in relation to the center of the bore. If it's not pointing across the chamber to the center, remove the plug and use an indexing washer to allow the plug to tighten in the correct position. If the thinnest washer doesn't do it, try the next thickest, then the next and so on until you get that plug indexed properly. Then do the other 7 the same way.
summit has washer kits...
ACC1001 14 mm tapered seat, 30 washers $20.69
...10 @ 0.010"
...10 @ 0.021"
...10 @ 0.032"
ACC1002 14 mm flat seat, 30 washers $20.69
...10 @ 0.043"
...10 @ 0.054"
...10 @ 0.064"
By the way, I wouldn't worry too much what the plugs look like until the motor is under load. The best way to do it is at the drag strip. Make a full, hard pass. As you pass the eyes, go to neutral and click the motor immediately. Coast to a stop and pull the plugs and read them. Lacking a drag strip, find a suitable stretch of road where you can do the same thing.
I have used this site many times to help understand spark plug results.
Spark Plug reading 101
I did not know that.
This probably sounds stupid, but should the open part of the plug be pointing straight up towards the top of the c.c. or straight down towards the top of the piston?
Mine have a little pop up, does that change what I want to do with the plugs?
Pointing the plug towards the promise land and porting heads have been the grounds of much research. I've seen some plugs benefit from pointing towards the exhaust valve but again it all depends on the head, engine, and piston. This is where one separates himself from the pack with extra power.,.,
~Ty