platinum or iridium?

[flyinlow]

The 446 has about 12000 miles on it now. I was using NGK standard plugs and I was thinking about puting NGK Platinum or Iridium Plugs in .

Anyone use either of these with Eddy heads and seen an improvment?

[charger2fast4u]

i have  a pretty much stock 440 6pack with a 4 barrel now instead of the 3 2 barrel carbs and i put the NGK iridium plugs in last time i changed plugs to try them out. needless to say i had to change the plugs a month later because they were causing backfiring rough idle and breaking up in the upper RPM's. put regular XR5's in and haven't had a problem since had the XR5's in since the end of last year. maybe you will have better luck then i did with them. just telling you my experience with them at around $50 for the plugs it wasn't worth it. i could of bought XR5's oil and filter for the price of the iridiums.

[frederick]

I've used the iridium plug and found out as flyinlow did, they don't last very long in a carburetted engine.
The car did start easier with the new iridium plug and got slightly better mileage, but I've too gone back to the normal plugs.

Cheers,

Frederick

[bull]

Seems most people recommend NGK XR5s on this board. Type "spark plugs" into the search box and you'll see what I mean.

[flyinlow]

I have bcpr6es-11 's in now. Sounds like an other set would be the best choice.   

Thanks  Craig

[firefighter3931]

I have bcpr6es-11 's in now. Sounds like an other set would be the best choice.   

Thanks  Craig

The BCPR-6ES plugs are the right choice for a pump gas compression e-head build.

The XR5's are a 13/16 iron head plug



Ron

[LUMI]

I have used short Accel 416S
only ones that fits with eddy heads and Hooker 2" heeders