Spark plug type for 502 EFI
 

Anyone have the cross references for the spark plugs for a 502 efi?

I haven't changed mine since the dyno run and I think one of them is fouled.

Thanks,
Shawn

Re: Spark plug type for 502 EFI
 

What Heads Are You Running? Are They Stock Or Aluminum

Re: Spark plug type for 502 EFI
 

Running the stock heads. Nothing extravagant.

Thanks :D

Re: Spark plug type for 502 EFI
 

NGKBR6FS
FED MOGUL QL77JC4

WWW.PARTMAN.COM

Re: Spark plug type for 502 EFI
 

Thanks bro! :D

Re: Spark plug type for 502 EFI
 

Whats the gap suppose to be??

Re: Spark plug type for 502 EFI
 

.040 I THINK THAT IS WHAT THEY ARE ALREADY SET AT

Re: Spark plug type for 502 EFI
 

Thanks, once again!! :D

Going to try to run it saturday in or around clear lake if the weather is descent! :evilb:

Re: Spark plug type for 502 EFI
 

If Your Out On Sunday And See Me Out Come On Over.


THE ARCH IS GONE :D

Re: Spark plug type for 502 EFI
 

Have to see what the weather is going to do. The weather looks like it will be warmer on saturday, but if if its good on sunday I might go out again.

Look for mine also.

Re: Spark plug type for 502 EFI
 

Stock plugs are RV15YC4 or MR43TS at .045.

Re: Spark plug type for 502 EFI
 

You may want to use a projected nose plug (such as NGK BPR6FS) instead of standard nose (NGK BR6FS). From Dennis Moore's BBC Performmance book;

"Spark plugs are an area of the ignition system where an increase in performance is available for very little expense. The increase in performance comes from switching from a standard nonprojected nose to a projected nose spark plug. Most professional high performance marine engine builders and tuners automatically switch to a projected nose plug as a matter of course, but for some reason, this is still a big secret to a lot of amateur or backyard mechanics. Projected nose spark plugs are more efficient at igniting the air/fuel mixture because the nose of the plug projects further into the combustion chamber".

Dave

Re: Spark plug type for 502 EFI
 

The MR43TS are extended tips.

Re: Spark plug type for 502 EFI
 

The 'M' marine have been discontinued.

The 'C' commercials are available.

So instead of MR43TS get the CR43TS.

Some places still have the marines, but it is typically what they have left in stock.