Spark Plugs

[Ralphy]

I'm sure it's here somewhere. But may I ask which plugs seem to work best for a 428 motor? Are there any modern plugs for this motor?

Ralphy

[ERA Chas]

Accel 416 if you have 14 mm plug holes. You don't say which heads you have.

[undy]

Originally Posted by Ralphy

I'm sure it's here somewhere. But may I ask which plugs seem to work best for a 428 motor? Are there any modern plugs for this motor?

Ralphy

Depends ... As Chas mentioned, what heads are you running?

[Ralphy]

I did forget to note I had cast iron heads. Thinking they all ran the same plug.

[Gunner]

Originally Posted by ERA Chas

Accel 416...

Why?

I am of the opinion that, excepting modern engines expecting to get 100k miles on a set (meaning platinum-plated), or engines with very high compression or other unusual characteristics, more depends on the plugs being clean and correctly gapped than any other factor. Champions are as good as ultra-special Ford Racing or Accel or Roush plugs. Especially as the plugs in these engines are about as accessible as they can be and re-gapping them every 1000-1500 miles is no chore at all.

Almost all of the claims about multi electrodes, U-electrodes, special skin effect, etc. are complete BS - either untrue or "true in a lab, but so what?" Just like 'leventy-blade, chromium dioxide unobtainium plated razors.

But then, I use a twin-blade razor myself... one blade on each side.

(Has anyone ever shown that, all other factors adjusted, one plug truly outperforms another? Worth a single HP?)

[Ralphy]

Gunner,
I can't say for 4 stroke vehicles, however years ago I had a Yamaha snowmobile. I ran Champion gold plated plugs. I swear I saw at least a 15% increase in power, awesome like I had a different motor. They lasted maybe 10 hrs. of run time and when they quite I had better have had fresh plugs, because the motor just died. They fouled out!

Re-gaping is good I'm sure.

[ERA Chas]

Originally Posted by Gunner

Why?

I am of the opinion that, ...

...(Has anyone ever shown that, all other factors adjusted, one plug truly outperforms another? Worth a single HP?)

Tell you why there Gunner...

While you don't say what you base your very expert opinion on, I can tell you what mine is based on.

In a two year period I documented the dyno results of approximately 520 street and race, aluminum- headed engines. The power ranged from 350 to 1157HP. The displacements ranged from 302 to 705 cubic inches. The designs were Ford, GM and Hemi based.
All were run on 416's. On LS type engines the choice was Accel 526S. The prototype builds for each engine combination were tested with Accels, Champ, FR, Bosch and NGK's.

Worth a single HP you ask? The Accels proved to yield 4 to 6 more HP and did so with clean, repeatable results with no degrading in performance under extensive (18 or more pulls) testing. At master WD pricing they were also the least expensive. Champions proved to be the least consistent -reading plug on every combination. Not what you want to optimize a combination. The NGKs which are essentially the same plug showed near identical results to Accels. Only their premium pricing made them less attractive.

I didn't say a word about tip design. On certain customer hot street or bracket race engines we trimmed the ground electrode back as the Pro Stock guys do. There was no need to regap them at any mileage interval-I've run them in my SO for 6 years with the grounds trimmed and when it's time to replace them, their gaps have not degraded. That's street and race usage.

The real reasons to use them is they make more power over a longer service life and they always tell a true story of what's going on in the chamber.

-And that's no BS.

[Gunner]

Good enough. Yours is, truly, the first opinion I've ever seen backed by significant experience. No question there is a vast amount of marketing-driven BS in the spark plug world (as elsewhere), and far too much unsupported anecdotal evidence. (I recall a guy who swore Champions blew his differential.)

I'm good with Accels next time.

[patrickt]

Originally Posted by Gunner

Good enough. Yours is, truly, the first opinion I've ever seen backed by significant experience.

How do you know Chas. isn't just making all that stuff up? He claims he owns an ERA, but I'm not so sure....

[ERA Chas]

Originally Posted by patrickt

How do you know Chas. isn't just making all that stuff up? He claims he owns an ERA, but I'm not so sure....

Oh it's an ERA alright-a REAL ERA...

[ERA Chas]

Originally Posted by Ralphy

I did forget to note I had cast iron heads. Thinking they all ran the same plug.

You have 13/16 plugs. Contact Barry at Survival and ask for a recommendation.

[Gunner]

Originally Posted by patrickt

How do you know Chas. isn't just making all that stuff up?

I don't.

What I do know is that [insert plural automotive part name here] are a religious subject - everyone has an opinion, few have any facts, and the debate over them has a microscopic signal to noise ratio.

Since I don't believe there is *much* difference between quality spark plugs, I am willing to take Chas's stated experience as a good enough basis to pick up Accels next time. And I do so knowing there is some engine master of equal or better experience out there who will swear Accels are complete crap that suck horsepower, break under load, scar cylinder heads, etc. etc. etc.