Swapping plugs; this can't be right.....
Thread Starter
Le Mans Master
Joined: Jun 2007
Posts: 7,801
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From: Crush your enemies, see them driven before you, and hear the lamentations of the women TX
Swapping plugs; this can't be right.....
I've got this 350 supposedly built up. It's never put out what I figured the build should have done. Needing to send the carb to Lars when he's back functional. In the mean time I pulled the plugs to swap them for whatever I could squeeze from it.
So..... got a set of Delco R44T plugs.
Pulled the first plug and it was crudded up on one side of both conductors.
It's also a Champion RC12YC with twice the thread length of the Delcos!
The Delcos have like 3/8" of thread.
The Champions are slightly physically longer and have like 11/16" of thread.
The heads are Edelbrock RPM Performers. No doubt that makes a difference.
Doesn't feel right. Should I just get the longer Champions to replace them with? I've only pulled the one plug so far and it didn't look happy.
So..... got a set of Delco R44T plugs.
Pulled the first plug and it was crudded up on one side of both conductors.
It's also a Champion RC12YC with twice the thread length of the Delcos!
The Delcos have like 3/8" of thread.
The Champions are slightly physically longer and have like 11/16" of thread.
The heads are Edelbrock RPM Performers. No doubt that makes a difference.
Doesn't feel right. Should I just get the longer Champions to replace them with? I've only pulled the one plug so far and it didn't look happy.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Find out what plug Edelbrock recommends for that head. Using a plug that's got a reach too short will bring the electrode up into the threaded area of the head- low power, carbon, incomplete combustion. A plug that's too long, sticks out in the chanber too far and will cause hot spots and detonation when the threads heat up where they're the thinnest.
If it's had plugs that were too short, make sure you clean the thread beofer you wind another plug in that hole- carbon build-up could possibly tear up the threads and then you'd have to put a heli-coil in there.
If it's had plugs that were too short, make sure you clean the thread beofer you wind another plug in that hole- carbon build-up could possibly tear up the threads and then you'd have to put a heli-coil in there.
Thread Starter
Le Mans Master
Joined: Jun 2007
Posts: 7,801
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From: Crush your enemies, see them driven before you, and hear the lamentations of the women TX
Already looking at Edelbrock.
Their site is abysmally slow and doesn't address that.
Their 800 number is at least as slow....
Their site is abysmally slow and doesn't address that.
Their 800 number is at least as slow....
Pro
Joined: Feb 2006
Posts: 718
Likes: 7
From: Jacksonville , NC
Find out what plug Edelbrock recommends for that head. Using a plug that's got a reach too short will bring the electrode up into the threaded area of the head- low power, carbon, incomplete combustion. A plug that's too long, sticks out in the chanber too far and will cause hot spots and detonation when the threads heat up where they're the thinnest.
If it's had plugs that were too short, make sure you clean the thread beofer you wind another plug in that hole- carbon build-up could possibly tear up the threads and then you'd have to put a heli-coil in there.
If it's had plugs that were too short, make sure you clean the thread beofer you wind another plug in that hole- carbon build-up could possibly tear up the threads and then you'd have to put a heli-coil in there.
When I installed my Patriot aluminum heads I had to go from a 11 mm reach plug to a 19 mm reach. Call Edlebrock with your heads and CR and they will give you the correct plug, not only for fitment but for heat range.
Thread Starter
Le Mans Master
Joined: Jun 2007
Posts: 7,801
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From: Crush your enemies, see them driven before you, and hear the lamentations of the women TX
.FWIW;
Excel 416S
Champion RC12YC/2071
NG FR4/5155
Autolite 3926
Thread Starter
Le Mans Master
Joined: Jun 2007
Posts: 7,801
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From: Crush your enemies, see them driven before you, and hear the lamentations of the women TX
Hmmmm.......
Wonder if I should still gap them the stock .035".......
Chasing down Champion website now.....
_______________
Dayum! Whereas the stock gap with the Delcos was .035"
Champion wants me to gap their's at .060"!
Wonder if I should still gap them the stock .035".......
Chasing down Champion website now.....
_______________
Dayum! Whereas the stock gap with the Delcos was .035"
Champion wants me to gap their's at .060"!
Last edited by Overlord; Apr 9, 2008 at 12:07 AM.
Safety Car
Joined: Jun 2005
Posts: 3,841
Likes: 0
From: Inver Grove Minnesota
If it is an HEI or similar stock style distributor ie. no cd box then I would run them at .035.
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Thread Starter
Le Mans Master
Joined: Jun 2007
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From: Crush your enemies, see them driven before you, and hear the lamentations of the women TX
I'll be checking the gap on the plugs coming out, but I'll be gapping the new ones to .035". Just hard to figure such a large disparity between the 2 numbers;
http://www.championsparkplugs.com/re...p?AAIA=1307607
http://www.championsparkplugs.com/re...p?AAIA=1307607
Thread Starter
Le Mans Master
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From: Crush your enemies, see them driven before you, and hear the lamentations of the women TX
Now I know why the ceramic insulator on the plugs is white.
So I can see them hiding behind the damn headers down there in the dark laughing at me.
I don't mind putting an open end wrench on the back of the plug socket, that's why it's a hex. I do kinda mind putting the open end wrench on the plug itself because the plug itself is almost too long to fit in there let alone get the plug socket on it. And, of course,the shape of the block doesn't want me to be able to turn the open end wrench.
Wait! I have those gear wrenches. Back inside to look at the laptop, ah! 5/8 is 16mm! Luckily I have a 15mm and a 17mm. With the tapered hex nut shape on the plug, I can slide the 15mm part way up on it. Even with the fine tooth ratchet, I can only get a tooth at a time cramming the wrench up on the taper of the nut.
Right rear plug was crudded up the worst. Almost no gap between the electrodes with the crud on it. Second from RR had oil on it. Didn't like that at all. Front right may have been put on before the headers were. Pretty crudded up too.
I'm betting those straight thru sockets (forget the name) would work wonders here. You know the ones, where the back of each socket is a hex like the back of the plug socket is, and the ratchet is a big open deal like my gear wrenches that fits over the outside of the socket.
Drinking the rest of the coffee before I go back into the garage and find creative ways of putting real torque on the last plug. Gotta get it all together before I can go out and get cigarettes; I'm out. My way of creating motivation.
So I can see them hiding behind the damn headers down there in the dark laughing at me.
I don't mind putting an open end wrench on the back of the plug socket, that's why it's a hex. I do kinda mind putting the open end wrench on the plug itself because the plug itself is almost too long to fit in there let alone get the plug socket on it. And, of course,the shape of the block doesn't want me to be able to turn the open end wrench.
Wait! I have those gear wrenches. Back inside to look at the laptop, ah! 5/8 is 16mm! Luckily I have a 15mm and a 17mm. With the tapered hex nut shape on the plug, I can slide the 15mm part way up on it. Even with the fine tooth ratchet, I can only get a tooth at a time cramming the wrench up on the taper of the nut.
Right rear plug was crudded up the worst. Almost no gap between the electrodes with the crud on it. Second from RR had oil on it. Didn't like that at all. Front right may have been put on before the headers were. Pretty crudded up too.
I'm betting those straight thru sockets (forget the name) would work wonders here. You know the ones, where the back of each socket is a hex like the back of the plug socket is, and the ratchet is a big open deal like my gear wrenches that fits over the outside of the socket.
Drinking the rest of the coffee before I go back into the garage and find creative ways of putting real torque on the last plug. Gotta get it all together before I can go out and get cigarettes; I'm out. My way of creating motivation.