I did a couple of searches looking for previous discussions on spark plug recommendations but did not see a list by brand type recommendation.

Any recommendations on plugs and wires for a 1979 928 4.5L CIS?

Thanks
Jim

 

As for plugs, these car seem to respond best to the good 'ol copper Bosch plugs.

If you look at the Owner's Manul (available by link in my signature) you will see they recommend the W8. Today's version of that would probably be the WR8DC.

If not available, I would recommend the NGK's. I believe the equivalent is BP5ES.

 

Another vote for Bosch coppers. Available from any of the 928 suppliers and probably at the autoparts store.

 

I've had Bosch platnum +4's in for about 10 years (25k miles) and have been very happy with them, but I think some folks don't like them, not sure why. I need to change to PorKen's recommended cooler Bosch copper plugs soon since I installed his chips.

 

These are extras since I ended up going one range colder for the SC install.

You can have these for $15.00 plus shipping if you want.

They have never been out of the box.

 

My car seems to like the newer multi-electrode Bosch Iridium jobs ...

 

$0.90 Motorcrafts seem to work fine to me.

 

From a performance standpoint you cannot beat copper. In a stock car I doubt you can tell much difference, so why spend the extra money?

The multi-point electrodes are for longevity, nothing else. They are very hard to properly gap which is why I stay away from them.

Late model VW engines are very picky. My friends VW Beetle (non-turbo) had a nasty miss-fire. Swapping out the Bosch Iridium plugs installed, for copper and the problem went away. I've seen the same thing with a few 1.8 Turbo Audi / VW's as well.

 

For the cost you can afford to replace them whenever you want to.

I'll do that every time I need to really get into the engine so roughly every other week.

(humor)

 

Anyone running Bosch silver (W7DSR)?

 

I've used NGK, Bosch copper, Bosch silver, and Bosch +4 and for me the best so far is +4.

 

My car must be the odd one out, as I tried +4 many years ago, and the car rana little rough. I don't know what role having AutoThority chips plays in the equation. Switching to single electrode Bosch platinums resolved the issue.

For what it's worth, right now I'm running NGK iridiums, and the old girl seems to like those the best from what I have tried thus far. Starts up smoothly and voltage is higher on dash compared to platinum plugs. I change the plugs regularly and my mileage is low, so wear shouldn't have been a factor.

 

Wow… and here I thought spark plugs were spark plugs (except for heat range). Yeah, some last longer than others, but they usually cost significantly more.

I thought all the hype about multi electrodes got debunked years ago. Sounds like the plug debate is about as heated as the oil debate. Does running Amsoil decrees the life expectancy of platinum?

 

They do last longer, there is no doubt about it. For people who want to go 100,000 miles without checking their plugs, they are perfect!

Some people also go 10,000+ miles between oil changes.

 

I only recommend what Porsche originally installed for stock cars.
WR8DC+ 78 to 82
WR7DC+ 83 to 91
WR7DTC 92 to 95