Spark plugs for my 383 - go colder?

[atlantadan]

ERE 383, 11.43 SCR, 8.59:1 dynamic. 220 PSI on a compression test. Always running 93 octane. The quench is spot on after talking with Lloyd and Karl. Moe's been putting in yeoman's duty tuning (and re-tuning) it to get rid of the knock counts, but they're still there. It happens mostly at part throttle under load. The NOx counts on the smog test were also high - but still legal, which tells me combustion temps are hot. Currently running the stock heat-range plugs.

I've been told to try colder plugs gapped to .035. Thinking about giving TR6's a try. Too cold or worth a go? Colder? Might help with pulling some heat out of the chamber too...

Thanks in-advance

Edit: Can't use TR6. TrickFlow heads need gasket-seat.

[DirtyBird1139]

Autolite 104s is what ive used

[SSlowBoat]

ERE 383, 11.43 SCR, 8.59:1 dynamic. 220 PSI on a compression test. Always running 93 octane. The quench is spot on after talking with Lloyd and Karl. Moe's been putting in yeoman's duty tuning (and re-tuning) it to get rid of the knock counts, but they're still there. It happens mostly at part throttle under load. The NOx counts on the smog test were also high - but still legal, which tells me combustion temps are hot. Currently running the stock heat-range plugs.

I've been told to try colder plugs gapped to .035. Thinking about giving TR6's a try. Too cold or worth a go? Colder? Might help with pulling some heat out of the chamber too...

Thanks in-advance
Try tr6 gapped to 033-035

I thought tr4 was colder?

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[Nostang 96z]

Give the Autolite tech line a call and tell them your combo. They will spec a plug that will work for your needs. They were very helpful in recommending plugs for my setup. the below chart is helpful to have as well:

http://www.strokerengine.com/dynoroom.html

[atlantadan]

Just to close the loop - I called NGK and gave them all the info. They spec'd a 7 heat-range plug for this car. BKR7E (gasket seat) gapped to .035

[atlantadan]

The 7's lasted a week before the car started missing on cold start. Went to the BKR6E's gapped to .035