T500 Spark Plugs

[mafd2]

I found some NOS B77-HC plugs (OEM T500 plug) and know they've been discontinued for some time. I think the replacement plug is the B7HS. So my question is what's the difference between the two plugs? Thanks

[Vintageman]

I am not sure what the difference is.

You can still get B-77HC on eBay

I have run the B7HS. Now running the Iridium version of them BPR7HIX with caps without resistor

Denso makes some too and others


This is interesting http://www.ozebook.com/compendium/t500_ ... pspecs.htm" onclick="window.open(this.href);return false;

And NGK calls out B7hs

[tricky1962]

Full info on the NGK codes is here

http://www.ngksparkplugs.com/techinfo/s ... berkey.pdf" onclick="window.open(this.href);return false;

But as I understand it, the 77 was a bit cooler than the 7, but not as cool as the 8. The difference was small though (as I understand it)

I'm currently running 7s but have used 6s in the past with no problem (but no high speed highway stuff either, all small roads)

[mafd2]

NGK says they were discontinued in 1983 and couldn't tell me the difference as their books don't go back that far.