Simple spark plug question
 

So i've discovered my car (stock 87 3.2) has Bosch WR8DC+ plugs. I came here to confirm weather they were correct or not, and it looks like i should be running WR7DC's

Any reason my car would have the 8's ? I assume i should switch to back to the 7's. Color of the plug looks good, and in fact they look fairly new.

Well, i think i just answered my own question. Looks like the hotter plug was installed to compensate for a low compression cylinder. #6 is much lower than the rest and the plug is oil fouled big time. :(

So, new question,...... why not run the 7's in the good holes, and the 8 in the oil fouled one ?

We run a 3.2 used on Track Days on an NGK Iridium '8' and it performs very well.

Aren't Bosch and NGK number scales opposite?

Todd

Yes they are.

While you are at it get some good plugs...NGK's