Well i'm going through my system and I was wondering what the plug gap is for

a 72 240Z. I read that it was .036 and i was wonderng if that was right.

I have some Iridium IX sparkplugs. Thanks

.031-.035 seems to be the acceptd range for an L24 w/points. Since you already have those Iridium plugs, run em but next time I'd recommend the standard NGK BP 6ES. You'll get differing opinions but the majority would agree.

Stephen is correct about the NGK plugs! Just about everyone with an L6 motor eventually discovers that the NGK BP 6ES just seems to work the best.

Tom

Since they are paid for, install and run your Iridium plugs for a hundred miles or so, then swap to the BP®6ES-betcha won't put the iridium in swap back-or buy them for the Z ever again!

Will

Everyone's right about the standard NGK plugs in a Z. Before you go regaping those iridium plugs though, DON'T!!!!! If you try to gap iridium plugs you will crack the ceramic. That tiny little iridium tip isn't strong enough to take the force of a plug gapper pressing the ground electrode out, it will give and crack the ceramic around it. Most of the iridiums usually have a warning on the box telling you not to regap the plugs.

I third the recommendation to use only NGKs. I have my engine back from Rebello and am using B8ES (no P and no R), but this is a heavily modded L28.

cool, thanks won't try to regap them. I'm trying to trouble shoot my engine seems to backfire through the carbs a little during the warm up stage. I have the carbs set at about 3.5 turns out. I thought maybe they where a little too lean.

The carbs will run lean during warm up unless the choke is set. I would swap to the standard NGK plugs now and see if your lean backfire doesnt go away. Your money would be better spent on switching to a newer 280Z electronic distributor with E12-80 module and a hotter coil. The swap is quite easy and it will provide a better overall ignition system.

  hd240z said:

The carbs will run lean during warm up unless the choke is set. I would swap to the standard NGK plugs now and see if your lean backfire doesnt go away. Your money would be better spent on switching to a newer 280Z electronic distributor with E12-80 module and a hotter coil. The swap is quite easy and it will provide a better overall ignition system.

But if you do that swap you'll want to go to the NGK B6ES-11 and gap them at .039-.043.

So the reg NGKs are fine, no need to get platinum NGKs ??

No, no need for the platinum, regular copper core NGKs really do work the best.

  sblake01 said:

But if you do that swap you'll want to go to the NGK B6ES-11 and gap them at .039-.043.

I've found that NGK BPR6EY-11 (V-Power) also work great with the E12-80 ignition, and might be easier to find in some places.