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davids2toys
September 17th, 2007, 06:51 PM
While doing my valve cover gaskets, I notice how much easier the plugs looked like they would be to change without the valve covers installed.
I pulled a plug out, it is a Champion RF91C, it seems to be burning good...I have no idea how old they are, or if they are even the right plug.
I have a 428, with CJ heads, MSD box.
What would be the correct plugs for this engine...also, what should the gap be.
I did search but only found small block info!

Naumoff
September 18th, 2007, 02:13 AM
David, Are those RF9YC? They are correct.

Motorcraft BF-32/ Resistor BSF-42C
Autolite 35 or 34/ Resistor 45 or 44
Champion F11YC or F-9YC /Resistor RF-11YC or RF9YC
Accel 378 /Resistor 675


Points distributor Gap 35
Electronic distributor Gap 44

If you are looking for performance you want to use non-resistor spark plugs. A resistor is exactly what the word implies. When the spark crosses the point of resistance some of the spark energy is lost. A resistor is like an electronic obstacle and could be the cause for a weak spark. Non-resistor spark plugs deliver a more powerful spark.

davids2toys
September 18th, 2007, 03:53 PM
David, Are those RF9YC? They are correct.

Motorcraft BF-32/ Resistor BSF-42C
Autolite 35 or 34/ Resistor 45 or 44
Champion F11YC or F-9YC /Resistor RF-11YC or RF9YC
Accel 378 /Resistor 675


Points distributor Gap 35
Electronic distributor Gap 44

If you are looking for performance you want to use non-resistor spark plugs. A resistor is exactly what the word implies. When the spark crosses the point of resistance some of the spark energy is lost. A resistor is like an electronic obstacle and could be the cause for a weak spark. Non-resistor spark plugs deliver a more powerful spark.

I would like to replace the champions with autolites because I have heard they are much better...every thing cross referances back to a Autolite resister 45, there is no such thing as a 44, at least not any more. There are no straight champions either, just resister. Believe it or not, the difference in champion RF11yc and RF9yc is the thread, I thought it would be the heat range!!!
Autolite does make a non resister but it is a racing plug, I think the numbers started with AR
I ended up buying R45's, but not sure if I should put them in.
What do you think about the racing autolites?
The Champion RF9yc I took out looked like it was burning nice, I dont want to end up with a problem, especially because it looks like you need to remove the valve covers to get the plugs out!!
Also, would you know the torque on the plugs, and I will be using a tiny bit of anti-sieze, unless that is a no no to...lol.

Naumoff
September 18th, 2007, 05:44 PM
Just guessing but it might be getting harder to find a variety of those pugs for the original CI heads. R45 should be fine.
I would run the racing plugs but that might just be me. :D
Here is a link to torque specs and aditional info.
http://www.autolite.com/pdf/TorqueSpecs.pdf


Installing Spark Plugs Without a Torque Wrench

14 and 18mm tapered seat plug – tighten 1/16 turn after finger tight;
14 and 18mm gasket seat plug– tighten 1/2 turn past finger tight;
12mm gasket seat plug – tighten 3/8 turn past finger tight;
10mm gasket seat plug – tighten 1/4 turn past finger tight.

NOTE: Spark plugs should be installed with clean and dry threads to avoid overtorquing or stretching
the spark plug which can, and often does, result in engine damage


I have changed my plugs with the valve covers on but if you have them off it is easier. I use a swivel spark plug socket with a long extension. Same thing we use on big block 67 - 70 Mustangs and Cougars.

Racing plugs are colder.

I found this info on the web,

Keep in mind the insulator nose length is a determining factor in the heat range of a spark plug, the longer the insulator nose, the less heat is absorbed, and the further the heat must travel into the cylinder head water jackets. This means the plug has a higher internal temperature, and is said to be a hot plug. A hot spark plug maintains a higher internal operating temperature to burn off oil and carbon deposits, and has no relationship to spark quality or intensity.
Conversely, a cold spark plug has a shorter insulator nose and absorbs more combustion chamber heat. This heat travels a shorter distance, and allows the plug to operate at a lower internal temperature. A colder heat range is necessary when the engine is modified for performance, subjected to heavy loads, or is run at a high rpm for a significant period of time. Colder spark plugs remove heat quicker, reducing the chance of pre-ignition/detonation. Failure to use a cooler heat range in a modified application can lead to spark plug failure and severe engine damage


http://www.ngksparkplugs.com/techinfo/spark_plugs/techtips.asp?nav=31000&country=US

davids2toys
September 18th, 2007, 06:21 PM
Just guessing but it might be getting harder to find a variety of those pugs for the original CI heads. R45 should be fine.
I would run the racing plugs but that might just be me. :D
Here is a link to torque specs and aditional info.
http://www.autolite.com/pdf/TorqueSpecs.pdf


Installing Spark Plugs Without a Torque Wrench
14 and 18mm tapered seat plug – tighten 1/16 turn after finger tight;
14 and 18mm gasket seat plug– tighten 1/2 turn past finger tight;
12mm gasket seat plug – tighten 3/8 turn past finger tight;
10mm gasket seat plug – tighten 1/4 turn past finger tight.

NOTE:

Spark plugs should be installed with clean and dry threads to avoid overtorquing or stretching
the spark plug which can, and often does, result in engine damage


I have changed my plugs with the valve covers on but if you have them off it is easier. I use a swivel spark plug socket with a long extension. Same thing we use on big block 67 - 70 Mustangs and Cougars.

Racing plugs are colder.

I found this info on the web,

Keep in mind the insulator nose length is a determining factor in the heat range of a spark plug, the longer the insulator nose, the less heat is absorbed, and the further the heat must travel into the cylinder head water jackets. This means the plug has a higher internal temperature, and is said to be a hot plug. A hot spark plug maintains a higher internal operating temperature to burn off oil and carbon deposits, and has no relationship to spark quality or intensity.
Conversely, a cold spark plug has a shorter insulator nose and absorbs more combustion chamber heat. This heat travels a shorter distance, and allows the plug to operate at a lower internal temperature. A colder heat range is necessary when the engine is modified for performance, subjected to heavy loads, or is run at a high rpm for a significant period of time. Colder spark plugs remove heat quicker, reducing the chance of pre-ignition/detonation. Failure to use a cooler heat range in a modified application can lead to spark plug failure and severe engine damage


http://www.ngksparkplugs.com/techinfo/spark_plugs/techtips.asp?nav=31000&country=US

Great info, thank you!!!
Do you know which size I have?


14 and 18mm gasket seat plug– tighten 1/2 turn past finger tight;
12mm gasket seat plug – tighten 3/8 turn past finger tight;
10mm gasket seat plug – tighten 1/4 turn past finger tight.

or how I can tell?
So which Autoliter racing plug would you run, knowing thay the RF9YC was burning good? Is there a downfall to using the racing plug!

Naumoff
September 19th, 2007, 04:41 AM
Probably 7/8" :D close to 18mm

Accel 378 did you try to find them?

Your on the street and the plugs look fine at an idle so running a colder plug would be fine. which is what racing plugs will be.


I have aluminum heads so my car takes a different sparkplug.

eliminator
September 19th, 2007, 05:26 AM
"NOTE:
Spark plugs should be installed with clean and dry threads to avoid overtorquing or stretching"

That is BS, if you have aluminum heads you better not install the spark plugs with dry threads, you better have some anti-seize on them. If not you will be stripping some threads when you attempt to remove them. Even on steel heads it's a problem. Now you don't have paint the anti-seize on, use sparingly, a little goes a long way.

Since spark plugs only require about 14-18 ft lbs of torque you can't stretch them. So another case of don't believe everything you read.

rdorman
September 19th, 2007, 07:47 AM
I always anti-seize the threads on the plug and put dielectric grease in the boot. The plain jane Autolite is hard to beat in our old school V8s. Dirt cheap to.

will butterworth
September 19th, 2007, 08:25 AM
that you thread into aluminum-bolt into alum. put tiny bit of antiseize on threads, now thats kinda my rule of thumb.Will-alabama

Brent
September 19th, 2007, 09:55 AM
There is no doubt Rick, Will , and Rick are correct.
Always anti-seze plugs into aluminum heads. It only takes a small ammount. It does not need to look like the Exxon Valdeze sank on your cylinder heads.

Dissimilar metals with totally different expansion characteristics.

On other items like intake bolts, etc. I use the ARP thread lubricant before torqued to spec. unless it a application for a thread locker.

davids2toys
September 19th, 2007, 02:58 PM
Probably 7/8" :D close to 18mm

Accel 378 did you try to find them?

Your on the street and the plugs look fine at an idle so running a colder plug would be fine. which is what racing plugs will be.


I have aluminum heads so my car takes a different sparkplug.
Never looked for the accel at all...I am installing the r45 autolites.
I got 2 plugs in last night with a 44 gap, and torqued them to 19 ft lbs. I hope to finish the job tonight and get the valve covers back on.
I have steel heads and did not use antisieze at all, I may pull them back out and put a tiny bit on. The metal that grips onto the plug inside the wire is a very very loose fit, but the wires look to be in perfect shape...should I be concerned:confused:

Brent
September 19th, 2007, 06:10 PM
Yes, I would use a thread lubricant either way.

No, you do not need to use a torque wrench on spark plug...nice and snug is good.

No, a loose end on a plug wire is not acceptable. You can either crimp it through the boot or pull the boot back and crimp it. It should "snap" when pushed on and it should spin but not have up and down "slop" in the connection.

Good choice on the Autolites.......Champion plugs %$@#&%
always have and always will.

Naumoff
September 19th, 2007, 07:21 PM
Never used anti-seize or thread lubricant on spark plugs in cast iron heads and never had a problem removing them.

Aluminum heads are a different story.


I would do as Brent said and pull back the boot and check the terminal.

davids2toys
September 19th, 2007, 10:25 PM
Yes, I did use a very small amount of anti sieze.
They do snap into place, but by design I believe, they move a real lot where the boot meets the wire. They are all straight boots, no 45's or 90's
One of my wires was missing a section of robber outside insulator, about a 1/4"x 1/4"...I painted it with two coats of liqid electrical tape.
I torqued everything to 18 lbs.
I used halomar on the valve cover / only on the valve cover side, and a ribbon of RTV on the int mani/head split...also carefully sanded down the intake gasket that was sticking up!
I even made an attempted on torquing the VC to 3 lbs!!!:eek:

The valve covers came out real nice...5 coats high heat satin clear, also decided to paint the inside line in the 427 script, body color (red)with a coat of clear.
Thanks for all the great info and advice...Dave:)

Naumoff
September 20th, 2007, 03:03 AM
Sounds good. We need pictures!:D

Brent
September 20th, 2007, 09:06 AM
We need pics!

davids2toys
September 21st, 2007, 08:52 AM
took it to a show last night, a few of the cobra guys commented favoably.
I took a few pictures, as soon as I download them, I will post.

davids2toys
September 21st, 2007, 04:52 PM
Here is few

davids2toys
September 21st, 2007, 04:56 PM
One of my wires was missing a section of robber outside insulator, about a 1/4"x 1/4"...I painted it with two coats of liqid electrical tape.


The wire is damaged because of the throttle linkage coming thru the footbox...is there a cure for this?

scott h
September 22nd, 2007, 12:17 PM
i would consider rerouting the wires, you can still have a nice look. one of my wires rubs against the footbox on the pass. side, i sleeved it with insulating sleeve used for brake and clutch lines, you could also use wire loom.

davids2toys
September 24th, 2007, 03:30 PM
i would consider rerouting the wires, you can still have a nice look. one of my wires rubs against the footbox on the pass. side, i sleeved it with insulating sleeve used for brake and clutch lines, you could also use wire loom.

If I had a longer wire, perhaps...I guess I will just keep an eye on it from now on!

Naumoff
September 25th, 2007, 12:50 AM
If I had a longer wire, perhaps...I guess I will just keep an eye on it from now on!

Looks good David. You have the old style boots at the distributor. Almost forgot about that style.
When you go to replace them. Get them so you can cut them to length and route them the way you want.
I guess if you are selling the engine let the next guy worry about it.:D

Aggressor
September 25th, 2007, 05:44 AM
I install my wires close to the lower surfaces of valve cover and heads. The accelerator linkage then has sufficient clearance for free operation. I've seen too many Cobra Replicas (Including Uniques)with free flying wires sliding against linkage rods. 90 degree boot angles allow for a close tuck. If you do it right the wires have a natural curve around the covers without a tight look.
-Geary

davids2toys
September 25th, 2007, 12:04 PM
Looks good David. You have the old style boots at the distributor. Almost forgot about that style.
When you go to replace them. Get them so you can cut them to length and route them the way you want.
I guess if you are selling the engine let the next guy worry about it.:D

Nah, I'm keeping it...so, which 8mm wires can i get that i will cut to lenth, have the old style boots, and have the 90 degree boots for the plugs that Aggressor is refering to. Also, should I go with suppressor wires or solid core?
I put a Bluestreak cap and rotor on yesterday, much more heavy duty, but I am trying to get used to the bluecolor!

Naumoff
September 25th, 2007, 04:00 PM
Nah, I'm keeping it...so, which 8mm wires can i get that i will cut to lenth, have the old style boots, and have the 90 degree boots for the plugs that Aggressor is refering to. Also, should I go with suppressor wires or solid core?
I put a Bluestreak cap and rotor on yesterday, much more heavy duty, but I am trying to get used to the bluecolor!

I painted my bluestreak cap black.:D

I have Accel High-temp super stock spiral core 8mm wires. But they have straight boots.
http://www.uniquecobra.com/gallery/files/1/4/6/9/113.JPG

davids2toys
September 25th, 2007, 04:47 PM
Those wires look great!Are the plugs ends straight or 90? I see the caps ends are 90 deg, so when you said straight, did you mean the plugs ends?
I tried painting my bluestreak on my old vette, the paint had soime issues sticking, and I did all the right thing to prep the cap

Naumoff
September 25th, 2007, 05:31 PM
Those wires look great!Are the plugs ends straight or 90? I see the caps ends are 90 deg, so when you said straight, did you mean the plugs ends?
I tried painting my bluestreak on my old vette, the paint had soime issues sticking, and I did all the right thing to prep the cap


Yes my plug ends are straight. Aggressor's plug ends are angled. The cap ends being 90* gives it a neater look. Number one is also set straight back so the wires will look nicer.

I just scuffed, cleaned and painted my cap and it is holding up very well.

davids2toys
September 25th, 2007, 08:46 PM
I install my wires close to the lower surfaces of valve cover and heads. The accelerator linkage then has sufficient clearance for free operation. I've seen too many Cobra Replicas (Including Uniques)with free flying wires sliding against linkage rods. 90 degree boot angles allow for a close tuck. If you do it right the wires have a natural curve around the covers without a tight look.
-Geary
Can you tell me which wires you have? Are they 8mm?

davids2toys
September 25th, 2007, 08:47 PM
Yes my plug ends are straight. Aggressor's plug ends are angled. The cap ends being 90* gives it a neater look. Number one is also set straight back so the wires will look nicer.

I just scuffed, cleaned and painted my cap and it is holding up very well.

I may have to try this painting gig again!!!

davids2toys
July 10th, 2010, 07:13 PM
Update:
Well, it is 3 years later and I am putting new wires on. I decided to pull a few plugs to see how they were burning and guess what, no deposits at all, nothing!!! These Autolites R-45 's have 5000k on them and look almost brand new:confused:
The Champion RF9yc 's I took out 3 years ago looked to be burning perfect, nice tan color. I am thinking maybe to hot or cold a plug. A buddy of mine said no deposit at all means it is running to lean?
I am contemplating going back to the Champions. What do you guys think?

Any input would be appreciated...Dave

Jim Harding
July 11th, 2010, 05:28 AM
Update:
Well, it is 3 years later and I am putting new wires on. I decided to pull a few plugs to see how they were burning and guess what, no deposits at all, nothing!!! These Autolites R-45 's have 5000k on them and look almost brand new:confused:
The Champion RF9yc 's I took out 3 years ago looked to be burning perfect, nice tan color. I am thinking maybe to hot or cold a plug. A buddy of mine said no deposit at all means it is running to lean?
I am contemplating going back to the Champions. What do you guys think?

Any input would be appreciated...Dave

I don't know what experience your buddy based his too lean theory on..... but I've never heard that a plugs heat range had anything to do with an engine running too lean or rich. That's a carb/injection issue. If the plugs aren't fouled, I wouldn't do a thing with the heat range of the plug you're using.

mkassab
July 11th, 2010, 06:40 AM
I agree with Jim. I'd also keep with the Autolites given they still "look like new"....... use the same plug
Mark

eliminator
July 12th, 2010, 01:59 PM
I agree, stay with the Autolites, a nice clean brownish color is what you want.:banana:

I used Champions ONE TIME,,,,my FE did not like them at all, after 300 miles they went in the trash.

davids2toys
July 12th, 2010, 07:35 PM
I don't know what experience your buddy based his too lean theory on..... but I've never heard that a plugs heat range had anything to do with an engine running too lean or rich. That's a carb/injection issue. If the plugs aren't fouled, I wouldn't do a thing with the heat range of the plug you're using.
No, I was the one who was wondering about the heat range of the Autolites vs the Champions... My buddy just stated that no deposits at all would be a sign of running to lean and suggested increasing jet sizes in the carb.
i made no changes except the different plugs, that is why I was wondering about the heat range difference.
So I am stumped, why would I all of a sudden run lean by just changing to a different plug?:confused:

davids2toys
July 12th, 2010, 07:37 PM
I agree, stay with the Autolites, a nice clean brownish color is what you want.:banana:

I used Champions ONE TIME,,,,my FE did not like them at all, after 300 miles they went in the trash.
Yes, I know, that is what the Champions looked like 3 years ago, these Autolites are spotless with no color at all!

davids2toys
July 15th, 2010, 07:54 PM
As much as I don't want to, for now I am getting a new set of Champions, and run then until winter and see what they look like. At this point in the summer I don't want to start screwing around with the carb jetting.
I will put the Autolites to the side and decide what to do later:confused:

mkassab
July 16th, 2010, 05:01 AM
Dave, changing sparkplugs wouldn't require you to do anything to the carb, let alone the jets. That would come into play only if you were running rich or lean.
Mark

davids2toys
July 16th, 2010, 05:41 AM
Dave, changing sparkplugs wouldn't require you to do anything to the carb, let alone the jets. That would come into play only if you were running rich or lean.
Mark
I know, that is why I am changing back to the Champions for now. When I went to the Autolights three years ago, the champions that were in the car were burning perfect! Now I checked the Autolighhts after 5000 miles and there is almost NO deposits at all!
So rather than try to adjust the carb to the autolites, I am opting to return to the Champions for now.
You will understand better if you read this tread from the beginning.

sllib
July 16th, 2010, 10:58 AM
Dave;
Did you ever paint your cap? A couple of years ago I called MSD about another problem and asked them if they made a black cap to fit the wide dizzy. At the time they didn't, so I asked if it was OK to paint my cap. I had two techs on the phone and they both just about choked to death trying to say "NO" (something about severe electrical shorting and the end of the world as we know it if I did it). If our last election cycle was any indication at least half of that came true, but how about the severe shorting?
Bill

davids2toys
July 16th, 2010, 11:09 AM
Dave;
Did you ever paint your cap? A couple of years ago I called MSD about another problem and asked them if they made a black cap to fit the wide dizzy. At the time they didn't, so I asked if it was OK to paint my cap. I had two techs on the phone and they both just about choked to death trying to say "NO" (something about severe electrical shorting and the end of the world as we know it if I did it). If our last election cycle was any indication at least half of that came true, but how about the severe shorting?
Bill
No, it is not painted!
That sounds pretty stupid to me, how in the world could paint on a cap cause shorting unless the paint had a conductive agent in it and you sprayed it into the holes where the wire ends would go:confused:
I think they must have thought you wanted to paint the inside of the cap...:D!

davids2toys
July 19th, 2010, 02:54 PM
I know, that is why I am changing back to the Champions for now. When I went to the Autolights three years ago, the champions that were in the car were burning perfect! Now I checked the Autolighhts after 5000 miles and there is almost NO deposits at all!
So rather than try to adjust the carb to the autolites, I am opting to return to the Champions for now.
You will understand better if you read this tread from the beginning.
Update:
I decided before I went back to the Champions to buy a brand new Autolite 45 to compare to the plugs presently in the car. I was amazed, there actually is deposits on those plugs very light gray color. I just never saw used plugs that clean. well I decided to NOT go back to the Champions.
I showed the plug to my buddy and he said he would still like to see it a tiny bit richer and recommend going up 1 jet size. I am just going to leave it for now, especially since I am considering going with the Holley 750 HP next year.

rldunn7
August 18th, 2010, 12:34 AM
NGK UR4...great plugs