Plug Change Interval????

[Marauderjack]

The OEM plugs are good for 100K miles but add a ProCharger and you are told to go with copper plugs and reduce the gap to .035"......Also, to change them every 10K miles???:confused::argue:

Well, my first plug change was at about 16K miles with no obvious problems.....BUT the new plugs were AMAZING!!!:bows: Mid-range power was greatly improved as was idle quality!!!:beer:

I guess the plugs degrade under pressure about like shocks go out....so slowly you don't really notice??:confused:

I replaced my plugs again yesterday at about 10K miles and AGAIN the difference is ASTONISHING!!!:eek:

Any of you other "Blower Folk" experience this phenomenon?? :cool:

BTW, The plugs look fine but something happens to them while performing "Under Pressure"??:shake:

Ideas??:help:

Marauderjack:burnout:

[RF Overlord]

'jack, who told you the plugs needed changing at 10,000 miles?

I'm not disputing that you had the effect you claim, but that seems like a very short interval.

Trilogy also suggest going to copper plugs with the same gap you were told, but they said they should last more like 30,000 miles.

[Zack]

I think .035 is a little loose for a blower car.
Id regap at .032 and re-evaluate.
Those wth 12+ lbs of boost should start at .030.

[Marauderjack]

I think .035 is a little loose for a blower car.
Id regap at .032 and re-evaluate.
Those wth 12+ lbs of boost should start at .030.

Funny thing Zack.....I actually gapped them at .032" this time to see if they work better.....9-10 PSI with mine!!:D

BTW.....ProCharger recommends 10K plug change??:confused: They also recommend "Slick 50" but I'm not about to put that crud in ANY motor of mine!!:shake:

Like I stated before the plugs LOOK fine but develop a "Phantom-Like" misfire that can only be felt in TC lockup but only very slightly!!:cool:

Marauderjack:burnout:

[Zack]

BTW, I run a .025 gap in my Kenne Bell Car.

I had spark blow out at anything looser than this.

[RF Overlord]

I stand corrected.

I just checked the Trilogy install manual and they do say .032"...

[greggash]

I have a Vortech blower on my car

I have been changing the plugs between 7 and 10k miles

why not, they are $1.25 each.

[Bradley G]

Ok, I guess I could spring for new plugs I got 25K on mine.

[Marauderjack]

Ok, I guess I could spring for new plugs I got 25K on mine.

Bradley....

I'd be interested to see if you feel the kind of difference I did??!!:cool: You may be very surprised....Let us know!!:D

Today I drove it more and the throttle response is really amazing!!:beer:

It is not the expense or time involved....it is the wear and tear on the plug holes that worries me....but so far they come out and go back in like it has iron heads and no, I don't torque them....:D

Marauderjack :burnout::burnout:

[Marauderman]

I have a Vortech blower on my car

I have been changing the plugs between 7 and 10k miles

why not, they are $1.25 each.

curious.....with what?

[dohc324ci]

Ok what about on non FI MM? I have about 85k and considering replacing them; the book says 100k? Are the diferrences significant.

[MCAT]

My question is why switch to copper? (just cheaper?) I paid 2.60 ea. for platinum plugs.

[RF Overlord]

MCAT, I heard that platinum plugs were not recommended for blower motors...something about the platinum not conducting heat away from the elctrodes as well as copper. Trilogy recommends Motorcraft copper plugs, 1 heat range cooler than stock.

[Local Boy]

You guys made me paranoid, now...

Going to change mine today...just for the hell of it...

ALOHA

[Zack]

You guys made me paranoid, now...

Going to change mine today...just for the hell of it...

ALOHA

I wouldnt if I were you.

My Blue has almost 60k on it with stock plugs, runs great.

Blower cars benefit though :up:

[Local Boy]

I have @ 20k on mine...and at $2.00 a pop = @ $18.40 (+tax) easy...

I'll try the NGK-TR6...

Besides, gives me something to do while I throw back some cold one's...

ALOHA

[magindat]

Make sure the motor is good and COLD before you start and make sure you schmutz the new plugs before installing.

[Local Boy]

Will do...Thanks

ALOHA

[Vortech347]

I use TR6's in all my DOHC cars. I change them every spring and fall.

[greggash]

curious.....with what?

Copper Plugs,
Autolite 103

cheap and decent
my car was tuned to 455RWHP with these plugs

[lifespeed]

for those with blowers and degrading spark performance, consider that the plug gap may be growing (eroding) slightly and there is a possibility that the ignition performance is marginal.

A misfire after only 10K miles could point to a barely-adequate ignition.

[vegasloner]

What gap will you be using, had an issue this morning and these are the plugs I am going to use as well. NGK-TR6

[BLACKMARAUDER04]

I ORDERED THESE FROM ROCK AUTO

<TABLE class=main><TBODY><TR class=part0><TD><TABLE class=parts><TBODY><TR><TD class=left><TABLE class=layout><TBODY><TR><TD>MOTORCRAFT Part # SP505 {#AGSF22CF6}
Category: Spark Plug</TD></TR></TBODY></TABLE></TD><TD class=right>More Info (http://info.rockauto.com/Motorcraft/sparkPlugs.htm)</TD></TR></TBODY></TABLE></TD><TD class=right>$1.63</TD><TD class=right>$0.00</TD><TD class=right>$1.63</TD><TD class=center><INPUT type=submit value="Add Part" name=addpart[0]></TD></TR></TBODY></TABLE>
Copper plug 1 grade cooler to go with my Reinhardt tune.
This was sugggested on numerous threads.

p.s. the L/M dealer wanted over $4.50 each

[magindat]

It is not the expense or time involved....it is the wear and tear on the plug holes that worries me....but so far they come out and go back in like it has iron heads and no, I don't torque them....:D

The key is changing them when the motor is COLD.

[Marauderjack]

for those with blowers and degrading spark performance, consider that the plug gap may be growing (eroding) slightly and there is a possibility that the ignition performance is marginal.

A misfire after only 10K miles could point to a barely-adequate ignition.

Not true in my case??:shake:

I checked the gap on the old ones (12K miles) and electrodes and gap were dead on.....right on .032" and looked new....no erosion!! :beer:

I think it has to do with insulator breaking down??:confused:

At any rate I plan to change these at 10K and see if I feel a difference!!:cool:

Marauderjack:burnout:

[lifespeed]

Not true in my case??:shake:

I checked the gap on the old ones (12K miles) and electrodes and gap were dead on.....right on .032" and looked new....no erosion!!

There are other ways to increase the effective resistance of the plug circuit. A thin coating of combustion debris. Pumping the cylinder full of more air/fuel mixture.

It is a well-known fact that blowers require hotter ignitions. All I'm saying is if it seems that regularly changing your plugs improves performance, it may be an indication that a stock ignition is not up to the job of lighting a supercharged mixture.

This has been common knowledge since the 1970s, and is the reason performance ignition companies exist.

[magindat]

No disagreement, there....

However, if a plug change costs less than $20 every 10K miles, that's $200 over a 100K lifespan. Several have spent $500-$1000 on 'upgraded' ignitions for our cars to no avail.

I think I'll go the proven $200 route....

[Marauderjack]

There are other ways to increase the effective resistance of the plug circuit. A thin coating of combustion debris. Pumping the cylinder full of more air/fuel mixture.

It is a well-known fact that blowers require hotter ignitions. All I'm saying is if it seems that regularly changing your plugs improves performance, it may be an indication that a stock ignition is not up to the job of lighting a supercharged mixture.

This has been common knowledge since the 1970s, and is the reason performance ignition companies exist.


You Boys are reading more into this than I have tried to state!!!:cool: I DON"T HAVE ANY MISFIRING!!!!:shake: I can immediately feel much increased midrange response......WOT is not any different??:shake:

BTW, what is the output voltage of OEM coils....50K??

Marauderjack:burnout:

[lifespeed]

You Boys are reading more into this than I have tried to state!!!:cool: I DON"T HAVE ANY MISFIRING!!!!:shake: I can immediately feel much increased midrange response......WOT is not any different??:shake:

BTW, what is the output voltage of OEM coils....50K??


I have felt similar improvements after swapping a stock ignition for a hot multiple-spark capacitive-discharge unit. No misfiring with stock ignition. It sounds like you're just feeling the temporary improvement in spark energy provided by clean, lower-resistance spark plugs. You could get the same improvement by cleaning your old spark plugs. There is nothing 'wrong' with them.

If increasing the spark energy improves engine performance (it usually does, unless the OEM system is really outstanding), then switching to a hotter ignition would provide the same or better improvement in response that you get when you change to new plugs, but it would last for the life of the plug.

Spark energy is Volts X Amps X Time. Voltage alone does not specify ignition performance. The more fuel and air you have in the cylinder the more resistance to electric current, requiring a higher voltage to achieve the same amps and spark energy.

This is all hotrodding 101. It isn't your spark plugs. ;)

[Marauderjack]

This is all hotrodding 101. It isn't your spark plugs. ;)

Call it what you wish but I still think our ignition system is up to the task with only 9-10 PSI of boost.............10K mile plug replacement is my course of action!!:beer:

BTW......this is "Maraudering 401"......I took the other course many years ago!!!:D

Marauderjack:burnout: