Spark Plug Recomendation?

[JMB]

I have a 66 Mustang with a totally stock 200 inline 6. The upgrades I am going to do is change my stock Distributor with the DUI from Classic Inlines. I am also going to use a Autolite 1100 Vaporizer Carb from (Pony Carbs).
Any recomendations on what type or brand of Spark Plugs I should buy for this set up? Thanks in advance.

 

[wallaka]

NGK IRIDIUM IX WR51X stock #7510.

The NGK plug is the latest in technology, it has a pin center electrode which requires less voltage to fire & the center electrode is iridium which will last 100,000 miles in a engine in good shape.

Best plug out there. IMO.

 

[Eric Rose]

The stock replacement copper electrode Motorcraft or Autolite plugs will work fine for you if you don't want to drop down the money for the iridium plugs. I am running the Motorcraft copper plugs spec'd for a '70 Mustang but I forget what the number is.

If you had a really radical setup you might benefit from dropping to a lower heat range, but a stock 200 with a DUI and a Vaporizer probably isn't enough to need cooler plugs.

 

[Gene Fiore]

I'm using the stock Autolite #46 plugs which seem to work just fine.

 

[wsa111]

wallaka wrote

NGK IRIDIUM IX WR51X stock #7510.

The NGK plug is the latest in technology, it has a pin center electrode which requires less voltage to fire & the center electrode is iridium which will last 100,000 miles in a engine in good shape.

Best plug out there. IMO.

This plug even works in my engine with 10.50 compression & 195# cranking compression.

You only get what you pay for.

If your compression is real low & you want to save $$$ use the #46 autolites. Bill

 

[JMB]

Thanks guys.
Would I be able to feel any difference at all with the way the engine performs if I use the NGK IRIDIUM IX WR51X stock #7510 over the Motorcraft or Autolite Plugs?

 

[Dougxox]

I have almost the same set up, and are running some platnum plugs... will have to dig up some paper work to find out which ones. Had a bit of trouble finding them as there is nothing listed for a 66 in line 6. had to do some cross referencing. When running platnum, iridium or some other high grade metal, you will get better performance and longer life than running a standard run of the mill plug.

 

[kirkallen143]

I am running the AP45's, Autolite Platinum, gapped at 0.045" which is one step colder (running 9.3:1 compression) and they are $2.79 ea. I have the DSII w/ Accel Super Stock coil and still have the resistor inline to the coil.

Kirk