indexing spark plugs
indexing spark plugs
I've heard a lot of conflicting info about how to index spark plugs properly. Some say to index them towards the intake valve, others say the exhaust, and some even say towards the piston. What are your thoughts on this matter? I'de appreciate some tips on indexing or any good "kits" out there.
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
I have mine indexed so that the piston dome doesn't hit the ground terminal. 
Have the gap opening either pointed straight into the cylinder or towards the intake valve. I't almost impossible to get every one of them pointed in the same direction. Mix and match the plugs in different holes and you shouldn't need an indexing washer on each one. Angled plug heads aim the spark plug towards the intake valve so you should have the gap pointing there also.
Spark plugs are cheap. But a few sets of them and keep swapping them around to get a perfect set. If you can, return the rest.
All indexing kits are good. Buy what you can afford.

Have the gap opening either pointed straight into the cylinder or towards the intake valve. I't almost impossible to get every one of them pointed in the same direction. Mix and match the plugs in different holes and you shouldn't need an indexing washer on each one. Angled plug heads aim the spark plug towards the intake valve so you should have the gap pointing there also.
Spark plugs are cheap. But a few sets of them and keep swapping them around to get a perfect set. If you can, return the rest.
All indexing kits are good. Buy what you can afford.
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