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Author Topic:   2 Questions: Fouled plugs and plug gap
unklshu
Gearhead

Posts: 682
From: San Bernardino, Ca
Registered: Jul 2001

posted 09-08-2001 02:57 PM     Click Here to See the Profile for unklshu   Click Here to Email unklshu     Edit/Delete Message   Reply w/Quote
My plugs on 1,2,3,4,5 and 7 are fouled. they look almost wet and very dark brown. Plugs 6 and 8 seem to be burning correctly. The above plugs also have slight smell of fuel and a little oil around the base.

I'm running a Mallory Unilite distributer with a Mallory High Fire coil NGK UR5 R(reduced) plugs and have them gapped at 44.

Any suggestions to the above fouled plugs and is this a good gap to run on the plugs?

I'm using reduced size plugs because of the header clearence.

Thanks

joe

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chips67
Gearhead

Posts: 651
From: louisville, ky, usa
Registered: Jul 2001

posted 09-08-2001 11:01 PM     Click Here to See the Profile for chips67   Click Here to Email chips67     Edit/Delete Message   Reply w/Quote
i would guess that your carb is too rich or the float bowls are set too high leaking fuel in through the boosters or somthing like that. unless it is oil, in which case could be bad rings or valve seals. i also think the reason the #6 and #8 are cleaner might be from a blown head gasket allowing coolant into those cylinders. hope its a gasket and not a cracket or warped head/block. this is my best guess, maybe a shot in the dark. i guess it would help to know the health of the engine and history. is there a mysterious loss of coolant from the radiator? is there any smoke from the exaust under startup or under acceleration? are the plugs oil fouled or black from running too rich? i dont think the plugs are the problem, although im not familiar with anything that i dont personally run. the hyfire ignition should keep them clean unless theres some other problem.

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67 coupe, 650dp and rpm intake on 5.0 with afr 165 heads, 4 speed, 4.11's.....best so far is [email protected] in 1/8 mile with 1.78 60ft. time.

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unklshu
Gearhead

Posts: 682
From: San Bernardino, Ca
Registered: Jul 2001

posted 09-08-2001 11:13 PM     Click Here to See the Profile for unklshu   Click Here to Email unklshu     Edit/Delete Message   Reply w/Quote
Well the engine seems healthy but I think my plug wire may be fried. After a long day I got some time to look them over and they are burned a bit from the header flange.

No coolant loss That I can see, in fact I did notice that the coolant reseviour was still right about where I last remember it.

What about the spark plug gap? Any recomendations??

joe

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chips67
Gearhead

Posts: 651
From: louisville, ky, usa
Registered: Jul 2001

posted 09-09-2001 02:38 AM     Click Here to See the Profile for chips67   Click Here to Email chips67     Edit/Delete Message   Reply w/Quote
yeah, should be readily available on the box they come in or by the parts store clerk. you want to gap the plug to that setting, usually the setting its already set at when you open the box. the ground tip exactly parallel to the tip face.

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67 coupe, 650dp and rpm intake on 5.0 with afr 165 heads, 4 speed, 4.11's.....best so far is [email protected] in 1/8 mile with 1.78 60ft. time.

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SteveLaRiviere
Administrator

Posts: 32961
From: Saco, Maine
Registered: May 99

posted 09-09-2001 07:56 PM     Click Here to See the Profile for SteveLaRiviere   Click Here to Email SteveLaRiviere     Edit/Delete Message   Reply w/Quote
Plugs do NOT come gapped, you have to gap them.

Joe, gap them at .035"

------------------
'70 Mustang Mach 1 M code 351C 4V/FMX/3.25 open
'72 Mustang Sprint Coupe 351C 4V/FMX/4.30 Trac Lok
'94 F-150 XL 5.8L/E4OD/3.55 Limited Slip
'97 Probe GTS 2.5L DOHC
Keep your driveway ALL Ford!!!

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unklshu
Gearhead

Posts: 682
From: San Bernardino, Ca
Registered: Jul 2001

posted 09-09-2001 11:44 PM     Click Here to See the Profile for unklshu   Click Here to Email unklshu     Edit/Delete Message   Reply w/Quote
Thanks Steve I will try that one out.

joe

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perk
Gearhead

Posts: 338
From: Staley,nc
Registered: Sep 2000

posted 09-10-2001 12:18 AM     Click Here to See the Profile for perk   Click Here to Email perk     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by SteveLaRiviere:
Plugs do NOT come gapped, you have to gap them.

Joe, gap them at .035"


Yep,that's right .

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chips67
Gearhead

Posts: 651
From: louisville, ky, usa
Registered: Jul 2001

posted 09-10-2001 11:39 AM     Click Here to See the Profile for chips67   Click Here to Email chips67     Edit/Delete Message   Reply w/Quote
i'm sure theres always an exception. ive never bought a new set that wasnt right, but i always check because thats the rules. tips should come exactly parrallel to the deck. if its the wrong heat range, or wrong design, you shouldnt try to correct by making the gap wider or shorter, this causes the surfaces to no longer be parrallel.

------------------
67 coupe, 650dp and rpm intake on 5.0 with afr 165 heads, 4 speed, 4.11's.....best so far is [email protected] in 1/8 mile with 1.78 60ft. time.

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SteveLaRiviere
Administrator

Posts: 32961
From: Saco, Maine
Registered: May 99

posted 09-10-2001 02:16 PM     Click Here to See the Profile for SteveLaRiviere   Click Here to Email SteveLaRiviere     Edit/Delete Message   Reply w/Quote
I don't think I've ever had a set of new plugs that came in the correct gap. The set I put in a couple of weeks ago were a mile off.

------------------
'70 Mustang Mach 1 M code 351C 4V/FMX/3.25 open
'72 Mustang Sprint Coupe 351C 4V/FMX/4.30 Trac Lok
'94 F-150 XL 5.8L/E4OD/3.55 Limited Slip
'97 Probe GTS 2.5L DOHC
Keep your driveway ALL Ford!!!

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SteveLaRiviere
Administrator

Posts: 32961
From: Saco, Maine
Registered: May 99

posted 09-10-2001 02:45 PM     Click Here to See the Profile for SteveLaRiviere   Click Here to Email SteveLaRiviere     Edit/Delete Message   Reply w/Quote
Here's what Autolite says:

Do Autolite spark plugs come pre-gapped from the factory?

Autolite and all spark plug manufacturers offer spark plugs pre-gapped in the most popular gap sizes. Because of the many gap sizes required, no one offers spark plugs properly gapped for every application. Gapping has always been the job of the installer. You can be sure that the Autolite? spark plug recommended for your application has been engineered to meet the requirements of your engine, and that the gap can easily be adjusted as required.

http://www.autolite.com/club/index.html

------------------
'70 Mustang Mach 1 M code 351C 4V/FMX/3.25 open
'72 Mustang Sprint Coupe 351C 4V/FMX/4.30 Trac Lok
'94 F-150 XL 5.8L/E4OD/3.55 Limited Slip
'97 Probe GTS 2.5L DOHC
Keep your driveway ALL Ford!!!

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Dr. Who
Gearhead

Posts: 164
From: Redwood City, Ca.
Registered: Sep 2001

posted 09-10-2001 04:31 PM     Click Here to See the Profile for Dr. Who   Click Here to Email Dr. Who     Edit/Delete Message   Reply w/Quote
I've talked to the plug folks and one thing that remains constant throughout all brands is gap. The gap needs to be wide enough to get some fuel molicules in with the air between the electrodes, this can be .045+ on very lean engines and .023 on rich runners. The gap is the stress point of the system so the smaller gap you can run will be easier on all the parts and deliver a hotter spark to the mix. The relationship of the ground electrode to the live one is moot, if you could see the little stream of spark jump it would be a very tiny lightning bolt and only needs a path about the size of a pin point. Some people even file the ground electrode to a point to ensure the spark will be unshrouded and out at the end.

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kid vishus
Gearhead

Posts: 4357
From: middle of NC
Registered: Oct 2000

posted 09-10-2001 04:34 PM     Click Here to See the Profile for kid vishus   Click Here to Email kid vishus     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by chips67:
....this causes the surfaces to no longer be parrallel.


If you take your time and gap them correctly, the surfaces will still be parallel.


I have never had a set out of the box that came with the gap I needed to run.

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Moneymaker
Administrator

Posts: 19686
From: Lyons, IL, USA
Registered: May 99

posted 09-10-2001 08:39 PM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
The exception to the rule are the new "AR" series racing plugs from Autolite which are precision factory pre-gapped at .032 and recomended to be used that way. I agree with STeve and recomend that you use a gap of .032 to .035. What is your timing set at? You should maybe try one heat range hotter also. What is the equivlant of that NGK slant eyed plug anyway?

------------------
Alex Denysenko
Co-Administrator and Moderator
NHRA/IHRA/SRA member
NHRA and IHRA SS/LA National Record Holder '00 & '01
Fleet of FoMoCo products
Moneymaker Bio
US Class Nationals link

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chips67
Gearhead

Posts: 651
From: louisville, ky, usa
Registered: Jul 2001

posted 09-10-2001 11:06 PM     Click Here to See the Profile for chips67   Click Here to Email chips67     Edit/Delete Message   Reply w/Quote
ok, not making this up....read somewhere that the life of the plug will be adversly affected by filing the ground electrode to a point. also that the life and wear of a plug depends on the surfaces being parallel. i swear i never had a set that wasnt right out of the box, just from personal experience. i dont believe the factory takes its time to set every gap on a .99 autolite plug but isnt there something in the way its made that keeps them all the same given if there is no damage in shipping? they must be manufactured by a machine. if not, i'd hate to be the guy spot welding all those ground tips on. i do always check mine just to be sure anyway, wouldnt tell anybody to just throw them in.

------------------
67 coupe, 650dp and rpm intake on 5.0 with afr 165 heads, 4 speed, 4.11's.....best so far is [email protected] in 1/8 mile with 1.78 60ft. time.

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chips67
Gearhead

Posts: 651
From: louisville, ky, usa
Registered: Jul 2001

posted 09-10-2001 11:11 PM     Click Here to See the Profile for chips67   Click Here to Email chips67     Edit/Delete Message   Reply w/Quote
hey, anybody here index their plugs? read also that the tip should face the exaust valve for best results...mark the plug on the glass and use that for a reference. i have aluminum heads and i tried to index but most didnt turn out right and i dont wanna strip the head. i heard you can get washers, but i havent found them anywhere.

------------------
67 coupe, 650dp and rpm intake on 5.0 with afr 165 heads, 4 speed, 4.11's.....best so far is [email protected] in 1/8 mile with 1.78 60ft. time.

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Moneymaker
Administrator

Posts: 19686
From: Lyons, IL, USA
Registered: May 99

posted 09-11-2001 11:52 AM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
Only the Autolite "AR" series plugs are precision gapped and they are considerably more than $.99 each! There is a nominal gain to be had by indexing plugs. Moroso offers the select washers.

------------------
Alex Denysenko
Co-Administrator and Moderator
NHRA/IHRA/SRA member
NHRA and IHRA SS/LA National Record Holder '00 & '01
Fleet of FoMoCo products
Moneymaker Bio
US Class Nationals link

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kid vishus
Gearhead

Posts: 4357
From: middle of NC
Registered: Oct 2000

posted 09-11-2001 04:05 PM     Click Here to See the Profile for kid vishus   Click Here to Email kid vishus     Edit/Delete Message   Reply w/Quote
I indexed a set one time, and I gained nothing. My opinion, unless you HAVE to for clearance reasons, it's a waste of time in anything short of a pro stock or "class" type engine where every single HP is highly sought after.

[This message has been edited by kid vishus (edited 09-11-2001).]

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unklshu
Gearhead

Posts: 682
From: San Bernardino, Ca
Registered: Jul 2001

posted 09-12-2001 09:39 AM     Click Here to See the Profile for unklshu   Click Here to Email unklshu     Edit/Delete Message   Reply w/Quote
I'm using the NGK plug because they come in reduced size for header clearance. I'm running windsor jr head with Hooker super comp and a regular size plug will hit the header.

If you now of a good plug that is of reduced size for headers and will not trash my radio let my know.
Thanks

joe

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Mark
Journeyman

Posts: 1
From: N.E. Ohio
Registered: Apr 2002

posted 09-12-2001 10:14 AM     Click Here to See the Profile for Mark   Click Here to Email Mark     Edit/Delete Message   Reply w/Quote

Test?

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