Can changing spark plugs change the exhaust note?

More complete combustion? It could make for a more lively exhaust note had the old components been that worn or of poor quality.

 

Not only to second what ^ said, but there is also that washing your car kinda thing. You do all that work and now your leaning your ear into it, listening in ways you probably didnt before, plus you WANT all your time and effort to be worth something, so it HAS to run better. Its like owning a car for over a year and then one day you hear the clock ticking. It obviously was always ticking, you just never heard it before.

 

Nuthin' psychosomatic about it....It sounds to me like it was money well spent!!! Now go DRIVE that car...

JIM

 

I thought that the QV's took the red resistor type extenders and the early carb cars took the black extenders.

 

yup, black ones with points, red ones on electronic

 

Do the QV's have resistor extenders? The 328's are just extenders.... no resistance.

 

My car always seems quicker after I change the oil! *S*

Seriously, if there IS an actual difference, then something was wrong with the car to begin with. Maybe you had a plug fouling or a bad wire.

Ken

 

It's nice when all (8) cylinders are actually firing correctly and completely --- isn't it!!!

 

For what it's worth, I changed all of the extenders on my '77 GTB and I used the red ones as opposed to the original black type. I was advised by an expert that the red are better than the black -- I kid you not. I doubt that there's much of a difference really, but a couple of my original black ones were in bad shape, so it was time to change them all anyway.

 

I am going to replace my 328 plugs with NGK iridium and I'm also replacing wires with Magnecor ones, starting next weekend.
I'm now very curious to know if there will be any difference like the one you explain.
I will let you know !

 

I had a sputter with the #2 car that went away when it was running with MSD. It just wouldnt run well on points. To make a long story short, points cars dont like high resistance in the high tension side. So lose the resistor plugs, resistor extensions and resistor wires. I finally dug back in and found two wires were open circuited, and one extender had physically melted at the wire terminal end and was burned out through the side. Somehow the MSD masked all the problems by forcing higher voltage through. But once the issues were dealt with, it actually ran better on points than it had EVER ran before. Thats not to say it wouldnt have run just as well with MSD, just that you wouldnt have known the system was so deteriorated. IOW, just adding MSD would have made someone think that MSD made more power, when in fact there is really no advantage (other than maintainance) if everything is up to snuff.

 

My QV extenders were red. They should be very low resistance.(just a few ohms max IIRC)

 

One thing is certain.... it would be much easier to spot the black marks left my arcing, if it occurs, on red extenders.

 

If it's just metal though the extender it should be zero ohms. If you see a slight resistance it will usually be caused by the test leads, their connections or less than perfect contact with the part being measured.

 

James, I don't think it's your imagination. I had a similar experience. After I installed the electromotive XDI in my gt4 I noticed a definite change in exhaust note. In my case the exhaust note got less raspy and quieter. At the time the XDI was installed I also installed new plug wires, extenders, spark plugs and it was timed and tuned properly so it's hard to say what may have caused the difference. Another factor (carbs) is that I'm sure I'm running a richer mix than I was before. That shouldn't be a factor in your case though. As long as you still enjoy the sound that's all that matters.