cut back the ground trap

Does anybody have a line on some indexing washers?

Any FE gains to be had by changing the heat range of your plugs?

The Z1 calls for a heat range of '4'.
I wonder of a '5' or '6' (with correct gap) would show any FE gains?

Low number = cooler plug
High number = hotter plug

For FE gains = cool or hot?

The heat range all depends on the company. In the NGK scale a 4 is hotter than a 5 or 6. The only reason you would see gains from going to a 5 and maybe a 6 would be because you are getting pre-ignition from a plug running too hot. I'd be weary about running a 6 in a car meant to have a 4. The colder you get the more likely the plug will foul and/or get buildup on it that will cause misfiring.

Champion and Bosch have a lower number for a colder plug. NGK and Denso go higher.

Your engine uses the following and if it has stock compression you only want to go up one step from that at the most. With Champion and Bosch they have a couple of heat ranges that are so close to each other that you can pretty much select from a small group of heat ranges.

NGK 4 -> 5
Denso 14 -> 16
Champion 11,12 -> 9,10
Bosch 8 -> 6,7

where the hell do you get the washer to index plugs??

Summit:
https://store.summitracing.com/egnsea...115+4294854256
(Not sure of the correct size/style).

I may pick up a set (for me and a few friends).

I just wonder which direction the electrode should point in a Z1.
I was thinking towards the timing belt... but who knows.

I have a set of 6's in my Z1 (with a 4 wire 02 and chipped P-28) (there is no issue that I can tell).

I was wondering if a set of 5's (or back to the OE 4's) would give any FE gain.

I will be back on the dyno (loading) in a few weeks and want to pick them up before then.

The ground strap should be on the exhaust side of the chamber.

Where can you buy the indexing washers? I need to get some too. Disregaurd this post I posted before reading everything.

I heard about this a long time ago. so how would you firgure out which washer to use?? keep trying them until you find the washer that indexs correctly??

You have to keep trying until you get it right.