spark plugs redux

[William F.]

Any advantage to platinum or iridium electrode spark plugs for mid year SB's over say Denso or NGK? Are any made that will fit and in heat range as AC R45 or R45S (assume all the newer plugs will be resistor).
Thanks

[Michael W.]

Re: spark plugs redux

The new generation plugs simply last longer (100K miles) than the traditional type which are good for 15-20K or so. No difference in performance, fuel consumption etc. etc.

[William F.]

Re: spark plugs redux

Last longer? You mean less prone to fouling(which is what I'm interested in) or some other form of lasting longer? Any in correct thread and heat range?

[Michael W.]

Re: spark plugs redux

'Last longer' in the context of a greatly reduced rate of electrode erosion. I'm not sure the new style plugs are inherently better at resisting fouling, but even if they are it would be a band-aid for other technical issues- wrong heat range, overly rich mixture, weak ignition etc.

[Duke W.]

Re: spark plugs redux

At the rate we drive our vintage Corvettes, most of us will be dead before we put on another 100K miles, and even if we live that long the plugs will probably be totally seized in the plug bores.

Stick with "two-dollar" spark plugs. They should easily last 15K miles, and if they are the right heat range and your fuel map isn't overly rich and oil consumption is no more than a quart in 1000 miles they should go 30K.

All my cars have conventional "two dollar" spark plugs, but since they accumulate no more than 1K miles per year, part of my maintenance program is just removing and reinstalling the plugs every five years to make sure they don't seize. (This is more or an issue with aluminum than iron heads.) While they're out I inspect them, and they always look near new with no significant deposits or electrode wear.

Duke

[Stuart F.]

Re: spark plugs redux

Remember the old "sand blast" plug cleaners back in the day? Now there was a sure plug killer if you wanted your engine to wind past 5000 RPM.

Guess I should follow Duke's routine and pull mine out pretty soon as I changed them before we moved here to Florida in 04. Glad I used Champs then as the AC's would surely be rusted in for life by now.

Stu fox

[Ralph P.]

Re: spark plugs redux

So what's the problem with the "sand blast" plug cleaners? Do they really degrade performance?

[Clem Z.]

Re: spark plugs redux

So what's the problem with the "sand blast" plug cleaners? Do they really degrade performance?

i believe that the porcelain get roughed up by the sand blasting causing the deposits stick more causing shorting. JMHO

[Duke W.]

Re: spark plugs redux

That's what I remember hearing years ago, but I still cleaned plugs every few thousand miles and reused them until I finally figured out that the sloppy distributor was the cause of my "plug fouling".

Some also claimed that sand would stick to the plugs and fall into the engine. After I cleaned and air blasted them with the plug cleaner I soaked them in solvent, cleaned them with and old toothbrush and air blasted them dry. I don't think any sand got into my engine

Boy, did I waste a lot of time on that!

Duke

[Dennis O.]

Re: spark plugs redux

I bought 8 Densu W14-U's from a guy in Canada for $2.00 each. He later emaiied me that he had 24 more, new in the box that he would sell for $.50 each, because he didn't want to "screw around with lawnmower plugs any more". I bought them.