Spark Plugs

[Cobain03]

are the high dollar plugs anybetter then the normal ones? such as the four prong vs single? i know they prolly are but could someone explain?

 

[Max Power]

Usually not.

If you are not misfirng, you don't need them.

 

[ravenblack67]

I'm sure there is some difference but would you even notice it? Timing, carb, fuel quality, exhaust, general engine condition, coil, points, wires are all significant variables in performance. I put my money into intake and exhaust as well as electronic ignition.

 

[65ShelbyClone]

No, they are not worth the money. They are a gimmick marketed to people who dont know how flame propagation works(ie, anyone who cant change their own sparkplugs).

The sparkplugs that came in most cars built in the last four decades did the job as they should. As we get more and more smog regs, the engineers have to consider new ways to meet them. Ironically, basic sparkplug design hasnt changed.

 

[thumper460]

We used to "side gap" the plugs for racing.. giving MORE flame to the fuel.. all these NEW ideas are old ideas.. just factory made!! cool?? With a carb ect .. plugs become fuel foul long befor they wear out.. stay copper core.. experiment with heat ranges and that is better off!! $7.00 a plug..?? come on!! LOL

Just me.............................

Thumper

 

[jbuening]

I bought a set of Bosch Platinums, still has a single prong but were the same price as the standard plugs were so why not? Did i notice any difference? Nope. Some claim you will get better fuel economy, you can increase your economy by the way you drive your car. Isn't really a way to prove they help IMO

 

[LMan]

save your money.

 

[HistoricMustang]

Here you go:

http://www.badasscars.com/techtips.html#Anchor11

Damn good tech even if from a Chevy guy!

HistoricMustang
www.historicmustang.com

 

[ForceFed70]

Standard platinum plugs are the only "performance" plugs that have any benifit. And even then, they're only better because they last longer.

 

[65ShelbyClone]

$7.00 a plug..?? come on!! LOL

The Denso Iridiums were roughly twice that when they came out not too many years ago. The rice crowd couldnt wait to spend $60 on plugs for a Honda.

 

[68 Coop]

Get yourself a set of Autolite 45's, gap them at around .034 or a LITTLE more, and you should be good to go.

 

[shotsy]

is .45 too much gap for a 9.5:1 compression ratio on a 351C with the durraspark conversion? Sorry to hijack BTW

 

[68 Coop]

Well, I gapped mine at .040, and they don't seem to work as well as .034. I am going back to the old gap on the next change. So to answer your question, in my opinion, YES IT IS.

 

[66StangFastback]

0.034 is spec gap for spark plugs on the 289. I don't know about the 351s but I do have the manual that says if anyone needs to know.

 

[shotsy]

I was affraid that I gapped em too big before I dropped the motor in, guess that I'll have to jack the motor and re gap them, could that cause me to run a little rich at idle if the spark isnt hot enough?

 

[cas69aus19]

I have heard that if you gap them to much like .045 that the compression can blow the spark out and cause problems..

 

[jbuening]

is .45 too much gap for a 9.5:1 compression ratio on a 351C with the durraspark conversion? Sorry to hijack BTW

What kind of cam do you have in there? If it is a stock cam, start out with 0.40 and work your way up. My cam is bigger than stock and it seems to work the best with a gap of 0.50 and i too have a duraspark box. I know people that run up to 0.60 with a multiple spark box and hot cams and the gap was set by dyno tuning.

 

[65ShelbyClone]

Unless you have a high energy coil, .035 is probably the safe max. I know that EFI 5.0s like I had specified somwhere around .050-.054, but the stock TFI coil and distributor were about like aftermarket parts already.

 

[cas69aus19]

So what would be a good gap to set with the accel 300+ box, coil, dist, and wires.?.

 

[shotsy]

Jacked the motor today and regapped the plugs to .35 and it seems to run better. I only broke one plug coming out and busted 2 knuckles. I love my cleveland