E3 Spark Plugs

[7Dcuda]

Has anyone tried E3 spark plugs in a 440? 

[Supercuda]

Don't waste your time. They shroud the spark kernel too much, causing misfires and poor running. They just aren't suited to these oldschool engines. They might shine in a stock, direct-fire ignition, EFI engine with computer control, but they stink in a carbureted hotrod.

[7Dcuda]

cool...thats the type info. I was looking for.

[Road_Runner]

So what are folks using in the 383 / 440s?  Is there a modern replacement for the Champion J11Y's I used to use?  NOS Champions are out of sight expensive.

[bordin34]

I use NGK XR5's in my 400. The only plug I will ever use is an NGK.

[Road_Runner]

I use NGK XR5's in my 400. The only plug I will ever use is an NGK.

Do you know which Champion plug this matchs heat range wise?  I ran J12Y's when they quit making J11Y's but wasn't racing the car then so it wasn't that big a deal.  And how modified is your 400?  I'm going to be running a lot of compression in my 383 or 438 if I go that way.

Thanks, Jim

[MEK-Dangerfield]

I'm using Autolite 85's.

[GoodysGotaCuda]

They nearly left my wife and i stranded 400 miles from home in her 4cyl Caliber. I just put them in before the trip, swapped to NGKs in the parking lot of an autozone. I'll never stray from a "standard" plug again, I am biased to NGKs too

[1970 RT Challenger 1970]

Bosch Platinum Plugs

[Oldschool]

I am running Champion 300's in the Beast.  This number is the new number for the old N9Y's. They run great. I run Autolite AR-52's at the track. So far, so good.....       

[Supercuda]

Although Bosch platinum plugs are excellent plugs, they are also not really suited to usage in an old hotrod. They worked well for me, but did not last as long as they should. The center electrode was burned out by the rich mixtures and high cylinder pressures. I lost 3 sparkplugs after about 35,000 miles. My personal bias is towards NGK, Denso, or Autolite, if Champions are not on the menu. No exotic plug designs are necssary, or advised.

[Chryco Psycho]

NGK has been the worst plug I have used althoiugh I have not tried the newer technology but the NGK will quit firing at the first hint of fouling
we tested virtually every plug available on a SS hemi a few years ago & the base Champions made more power , it was exactly propotionate the more $$ you spent on a plug the more power it lost

[wiging19]

NGK has been the worst plug I have used althoiugh I have not tried the newer technology but the NGK will quit firing at the first hint of fouling
we tested virtually every plug available on a SS hemi a few years ago & the base Champions made more power , it was exactly propotionate the more $$ you spent on a plug the more power it lost

Great topic 7Dcuda!  Some of the feedback is very interesting. 

[bordin34]

The XR5 should be fine for basically any big-block.

[mojavered]

I think any of these will work;
NGK P/N:   R5670-6
NGK STK:   2746
Accel:   138
AC Delco:   R44S
Bosch P/N:   WR9FC
Bosch STK:   7516
Champion P/N:   RJ14YC
Champion STK:   63
Denso P/N:   W20PR-U
Denso STK:   5046
Mopar:   2444870
Motorcraft P/N:   AS42C
Motorcraft STK:   49
Napa:   X701
Prestolite:   14-32

I like the autolite.  My dad and his mechanic like NGK though.  Pick and find one you like.