indexing spark plugs
#11
#12
RE: indexing spark plugs
What engine is it??
If its the old DI 3.9 I would say that the exaust valve is at 11 oclock on the 2 cylinders towards the front
and at 1 oclock on the 2 cylinders towards the firewall... Looking at the Drivers Side Bank..
Opposite on the Passenger side..
Exaust valves appear to be the outermost valves..
This kind of makes sense as the plugs in front are angled towards the front, and those by the firewall
are pointed towards the firewall..
This is just from looking at the Rave manual..
Have a look yourself..
And see what you think..
http://www.landroverresource.com/
If its the old DI 3.9 I would say that the exaust valve is at 11 oclock on the 2 cylinders towards the front
and at 1 oclock on the 2 cylinders towards the firewall... Looking at the Drivers Side Bank..
Opposite on the Passenger side..
Exaust valves appear to be the outermost valves..
This kind of makes sense as the plugs in front are angled towards the front, and those by the firewall
are pointed towards the firewall..
This is just from looking at the Rave manual..
Have a look yourself..
And see what you think..
http://www.landroverresource.com/
#15
#16
RE: indexing spark plugs
honestly you would need a swirl pattern of the chamber comming up on compression. they thought up indexing when hp were junkies were dumping tones of fuel into engines to try for more power. carbs would not keep the fuel atomized and if they kept the open side of the plug "AWAY" from the incomming charge they were less likely to foul. with current fuel injection our mixtures stay atomized and burn near perfecto. also keep in ind that half of your plugs fire from the ground electrode to the center, and the the other fire from the center to the ground, not sure if this could have any effect on on indexing plugs in a DIS.so with the bosch 4's when there is wear the arc wil continue around the plug from the electrodes closest together. i personally had no luck with the things and run theel cheapo's.
Would be interested knowing if this coould have any real positive effect on fuel econ though..
Would be interested knowing if this coould have any real positive effect on fuel econ though..
#17
#18
RE: indexing spark plugs
well I ordered the wrong indexing washers (tapered instead of flat) I went ahead and indexed the plugs with a marker. I am going to run it with the new iridiums for a while then swap out the washers. That way I will get a better idea how much indexing improves fuel mileage.
2 plugs are in a good location, 4 are in an ok location and 2 are in a bad location (ground electrode pointing towards intake valve).
2 plugs are in a good location, 4 are in an ok location and 2 are in a bad location (ground electrode pointing towards intake valve).
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marsyas
Discovery II
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02-25-2021 08:11 AM